METHOD AND APPARATUS FOR ALIGNING POWER SAVINGS CLASSES

• US 20100110950A1
• Filed: 11/05/2008
• Published: 05/06/2010
• Est. Priority Date: 11/05/2008
• Status: Abandoned Application

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Chiu, Yu-Min, Kone, Mamadou
• Application Number:
  US12/265,163
• Publication Number:
  US 20100110950A1
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method for power savings in a wireless communications network, including selecting all Type-1 power savings classes (PSCs), selecting all Type-2 PSCs, and selecting all Type-3 PSCs. The method further includes aligning the Type-1 PSCs of the device, if more than one Type-1 PSC is selected, and aligning the Type-2 PSCs of the device, if more than one Type-2 PSC is selected. The method also includes aligning the two or more aligned Type-1 PSCs or, if only one Type-1 PSC is selected, the Type-1 PSC, and the two or more aligned Type-2 PSCs or, if only one Type-2 PSC is selected, the Type-2 PSC, if there is at least one Type-1 PSC and at least one Type-2 PSC. The method may further include aligning the Type-3 PSCs with the aligned Type-1 and Type-2 PSCs, if there is at least one Type-3 PSC and at least one Type-1 or Type-2 PSC.

Claims

1. A method for power savings in a wireless communications network, comprising:

selecting all Type 1 power savings classes, if present on a device;

selecting all Type 2 power savings classes, if present on the device;

selecting all Type 3 power savings classes, if present on the device;

aligning the selected Type 1 power savings classes of the device, if more than one Type 1 power savings class is selected;

aligning the selected Type 2 power savings classes of the device, if more than one Type 2 power savings class is selected;

aligning the two or more aligned Type 1 power savings classes or, if only one Type 1 power savings class is selected, the selected Type 1 power savings class, and the two or more aligned Type 2 power savings classes or, if only one Type 2 power savings class is selected, the selected Type 2 power savings class, if there is at least one selected Type 1 power savings class and at least one selected Type 2 power savings class; and

aligning the selected Type 3 power savings classes with the aligned Type 1 and Type 2 power savings classes, if there is at least one selected Type 3 power savings class and at least one Type 1 or Type 2 power savings class.

2. The method as in claim 1, further including communicating the alignment of any Type 1, Type 2, or Type 3 power savings classes to a base station.

3. The method as in claim 1, wherein:

each of the one or more Type 1 power savings classes has a series of equal fixed duration listening windows alternating with a series of sleep windows, and wherein each sleep window has twice a duration of a previous sleep window, up to a maximum sleep window duration, and an initial sleep window duration is greater than or equal to the listening window fixed duration;

each of the one or more Type 2 power savings classes has a series of equal fixed duration listening windows alternating with a series of equal fixed duration sleep windows and the sleep window duration is greater than the listening window duration; and

each of the one or more Type 3 power savings classes has a sleep window wherein durations and separations of an expected time period of activity and the sleep window is set based on an expected arrival of a next portion of data or next expected ranging request.

4. The method as in claim 1, wherein aligning the selected Type 1 power savings classes of the device includes:

sorting the selected Type 1 power savings classes in order of increasing duration of initial sleep windows of the selected Type 1 power savings classes to define Type 1 power savings class ranked pairs;

aligning as a Type 1 power savings class twice length pair two Type 1 power savings classes for which the initial sleep window of a first Type 1 power savings class of the Type 1 power savings class twice length pair has twice a duration of the initial sleep window of a second Type 1 power savings class of the Type 1 power savings class twice length pair, the aligning including starting the second Type 1 power savings class at a time equal to the initial sleep window duration of the first Type 1 power savings class plus a duration of a listening window of the first Type 1 power savings class; and

aligning two Type 1 power savings classes in the Type 1 power savings class ranked pair, Type 1 power savings class ranked pair by Type 1 power savings class ranked pair, in the sorted order of increasing duration of the initial sleep windows of Type 1 power savings classes, except when the aligning of the Type 1 power savings class ranked pair changes an alignment of any Type 1 power savings class twice length pair.

5. The method as in claim 4, wherein aligning two Type 1 power savings classes in the Type 1 power savings class ranked pair, Type 1 power savings class ranked pair by Type 1 power savings class ranked pair, in the sorted order of increasing duration of the initial sleep windows of the Type 1 power savings classes, includes:

aligning the Type 1 power savings class ranked pair, for which a difference between an initial sleep window of a first Type 1 power savings class and an initial sleep window of a second Type 1 power savings class of the Type 1 power savings class ranked pair is an odd number of frames, by starting the Type 1 power savings class of the Type 1 power savings class ranked pair having a shorter duration initial sleep window after starting of the Type 1 power savings class of the Type 1 power savings class ranked pair having a longer duration initial sleep window, at a time equal to a difference between respective durations of the initial sleep windows of the Type 1 power savings class ranked pair; and

aligning the Type 1 power savings class ranked pair, for which the difference between the initial sleep window of the first Type 1 power savings class and the initial sleep window of the second Type 1 power savings class of the Type 1 power savings class ranked pair is an even number of frames, by starting both Type 1 power savings classes of the Type 1 power savings class ranked pair at the same time.

6. The method as in claim 1, wherein aligning the selected Type 2 power savings classes of the device includes:

sorting the selected Type 2 power savings classes in order of decreasing respective durations of the selected Type 2 power savings classes into Type 2 power savings class ranked pairs;

determining a greatest common divisor for each Type 2 power savings class ranked pair, a greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes;

determining a difference between the respective durations for each Type 2 power savings class ranked pair, the greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes;

determining a number of rounds for each selected Type 2 power savings class to complete a cycle for each Type 2 power savings class ranked pair, the greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes;

determining a start time for each Type 2 power savings class ranked pair, the greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes; and

applying the determined start time for each Type 2 power savings class ranked pair.

7. The method as in claim 6, wherein determining a start time for each Type 2 power savings class ranked pair includes:

aligning a Type 2 power savings class ranked pair, in which the durations of the two Type 2 power savings classes are equal, by starting the two Type 2 power savings classes of the Type 2 power savings class ranked pair, at the same time;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to a Type 2 power savings class with the shorter duration of the Type 2 power savings class ranked pair, by starting the two Type 2 power savings classes of the Type 2 power savings class ranked pair, at the same time;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to one, a duration of a sleep window of a first Type 2 power savings class is greater than a duration of a sleep window of a second Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the listening window of the second Type 2 power savings class is greater than a duration of the listening window of the first Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having a shorter duration sleep window after the start of the Type 2 power savings class with a longer duration sleep window, at a time equal to a difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to one, a duration of a sleep window of a first Type 2 power savings class is greater than a duration of a sleep window of a second Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the listening window of the first Type 2 power savings class is greater than or equal to the duration of the listening window of a second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to a difference between respective durations of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to one and the duration of a sleep window of the first Type 2 power savings class is less than or equal to the duration of a sleep window of a second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal the difference between the respective durations of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal one or in which the greatest common divisor does not equal the duration of the shorter Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the sleep window of the first Type 2 power savings class is greater than the duration of the sleep window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to an absolute value of a difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair, but if a time equal to an absolute value of a difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair is greater than a listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal one or in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal the duration of the shorter Type 2 power savings class, the duration of the sleep window of the second Type 2 power savings class is greater than the duration of the sleep window of the first Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the listening window of the first Type 2 power savings class is greater than the duration of the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to an absolute value of a difference between the respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair, but if the time equal to the absolute value of the difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair is greater than a listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair; and

aligning remaining Type 2 power savings class ranked pairs in which a greatest common divisor of the Type 2 power savings class ranked pair does not equal one or in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal a duration of the shorter Type 2 power savings class by starting the Type 2 power savings class with the shorter duration after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to a difference between the respective durations of first and second Type 2 power savings classes of the Type 2 power savings class ranked pair, but if the time equal to the difference between respective durations of first and second Type 2 power savings classes of the Type 2 power savings class ranked pair is greater than a listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at the time equal to the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair.

8. The method as in claim 1, wherein aligning the two or more aligned Type 1 power savings classes or, if only one Type 1 power savings class is selected, the selected Type 1 power savings class, and the two or more aligned Type 2 power savings classes or, if only one Type 2 power savings class is selected, the selected Type 2 power savings class, includes:

determining an aligned Type 1 power savings class which will be the last to start;

determining an aligned Type 2 power savings class with the shortest duration;

aligning the determined Type 1 power savings class with the determined Type 2 power savings class if a duration of a sleep window of the determined Type 2 power savings class is greater than a duration of an initial sleep window of the determined Type 1 power savings class and a duration of a listening window of the determined Type 2 power savings class is also greater than a duration of a listening window of the determined Type 1 power savings class, by starting the determined Type 1 power savings class at a time after the determined Type 2 power savings class equal to a difference between respective durations of the determined Type 2 power savings class sleep window and the determined Type 1 power savings class initial sleep window;

aligning the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 1 power savings class initial sleep window is greater than the duration of the determined Type 2 power savings class sleep window and the duration of the determined Type 1 power savings class listening window is also greater than the duration of the determined Type 2 power savings class listening window, by starting the determined Type 2 power savings class at a time after the determined Type 1 power savings class equal to a difference between the respective durations of the determined Type 1 power savings class initial sleep window and the determined Type 2 power savings class sleep window;

aligning the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 2 power savings class sleep window is greater than or equal to the duration of the determined Type 1 power savings class initial sleep window and the duration of the determined Type 1 power savings class listening window is also greater than or equal to the duration of the determined Type 2 power savings class listening window, by starting the determined Type 1 power savings class and the determined Type 2 power savings class at the same time;

aligning the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 2 power savings class sleep window is equal to the duration of the determined Type 1 power savings class initial sleep window and the duration of the determined Type 2 power savings class listening window is greater than the duration of the determined Type 1 power savings class listening window, by starting the determined Type 1 power savings class at a time after the determined Type 2 power savings class equal to an absolute value of a difference between respective durations of the determined Type 2 power savings class and the determined Type 1 power savings class; and

aligning the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 1 power savings class initial sleep window is greater than the duration of the determined Type 2 power savings class sleep window and the duration of the determined Type 2 power savings class listening window is greater than or equal to the duration of the determined Type 1 power savings class listening window, by starting a determined power savings class with the shorter duration at a time after a determined power savings class with the longer duration equal to the absolute value of the difference between the respective durations of the determined Type 2 power savings class and the determined Type 1 power savings class.

9. The method as in claim 1, wherein aligning the selected Type 3 power savings classes with the aligned Type 1 and Type 2 power savings classes includes matching a start time of the Type 3 power savings class with a start time of a last to start Type 1 power savings class or Type 2 power saving class.

10. The method as in claim 1, wherein the wireless communications network is compliant with IEEE 802.16e standard.

11. A wireless communication mobile station for wireless communication, the wireless communication mobile station comprising:

at least one memory to store data and instructions; and

at least one processor configured to access the memory and configured to, when executing the instructions;

select all Type 1 power savings classes, if present on a device;

select all Type 2 power savings classes, if present on the device;

select all Type 3 power savings classes, if present on the device;

align the selected Type 1 power savings classes of the device, if more than one Type 1 power savings class is selected;

align the selected Type 2 power savings classes of the device, if more than one Type 2 power savings class is selected;

align the two or more aligned Type 1 power savings classes or, if only one Type 1 power savings class is selected, the selected Type 1 power savings class, and the two or more aligned Type 2 power savings classes or, if only one Type 2 power savings class is selected, the selected Type 2 power savings class, if there is at least one selected Type 1 power savings class and at least one selected Type 2 power savings class; and

align the selected Type 3 power savings classes with the aligned Type 1 and Type 2 power savings classes, if there is at least one selected Type 3 power savings class and at least one Type 1 or Type 2 power savings class.

12. The wireless communication mobile station as in claim 11, wherein the at least one processor is further configured to execute instructions including communicating the alignment of any power savings classes to a base station.

13. The wireless communication mobile station as in claim 11, wherein:

each of the one or more Type 1 power savings classes has a series of equal fixed duration listening windows alternating with a series of sleep windows, and wherein each sleep window has twice a duration of a previous sleep window, up to a maximum sleep window duration, and an initial sleep window duration is greater than or equal to the listening window fixed duration;

each of the one or more Type 2 power savings classes has a series of equal fixed duration listening windows alternating with a series of equal fixed duration sleep windows and the sleep window duration is greater than the listening window duration; and

each of the one or more Type 3 power savings classes has a sleep window wherein durations and separations of an expected time period of activity and the sleep window is set based on an expected arrival of a next portion of data or next expected ranging request.

14. The wireless communication mobile station as in claim 11, wherein the at least one processor, when executing the instructions to align the selected Type 1 power savings classes of the device, is further configured to, when executing instructions:

sort the selected Type 1 power savings classes in order of increasing duration of initial sleep windows of the selected Type 1 power savings classes to define Type 1 power savings class ranked pairs;

align as a Type 1 power savings class twice length pair two Type 1 power savings classes for which the initial sleep window of a first Type 1 power savings class of the Type 1 power savings class twice length pair has twice a duration of the initial sleep window of a second Type 1 power savings class of the Type 1 power savings class twice length pair, the aligning including starting the second Type 1 power savings class at a time equal to the initial sleep window duration of the first Type 1 power savings class plus a duration of a listening window of the first Type 1 power savings class; and

align two Type 1 power savings classes in the Type 1 power savings class ranked pair, Type 1 power savings class ranked pair by Type 1 power savings class ranked pair, in the sorted order of increasing duration of the initial sleep windows of Type 1 power savings classes, except when the aligning of the Type 1 power savings class ranked pair changes an alignment of any Type 1 power savings class twice length pair.

15. The wireless communication mobile station as in claim 14, wherein the at least one processor, when executing the instructions to align two Type 1 power savings classes in the Type 1 power savings class ranked pair, Type 1 power savings class ranked pair by Type 1 power savings class ranked pair, in the sorted order of increasing duration of the initial sleep windows of Type 1 power savings classes, is further configured to, when executing instructions:

align the Type 1 power savings class ranked pair, for which a difference between an initial sleep window of a first Type 1 power savings class and an initial sleep window of a second Type 1 power savings class of the Type 1 power savings class ranked pair is an odd number of frames, by starting the Type 1 power savings class of the Type 1 power savings class ranked pair having a shorter duration initial sleep window after starting of the Type 1 power savings class of the Type 1 power savings class ranked pair having a longer duration initial sleep window, at a time equal to a difference between respective durations of the initial sleep windows of the Type 1 power savings class ranked pair; and

align the Type 1 power savings class ranked pair, for which the difference between the initial sleep window of the first Type 1 power savings class and the initial sleep window of the second Type 1 power savings class of the Type 1 power savings class ranked pair is an even number of frames, by starting both Type 1 power savings classes of the Type 1 power savings class ranked pair at the same time.

16. The wireless communication mobile station as in claim 11, wherein the at least one processor, when executing the instructions to align the selected Type 2 power savings classes of the device, is further configured to, when executing instructions:

sort the selected Type 2 power savings classes in order of decreasing respective durations of the selected Type 2 power savings classes into Type 2 power savings class ranked pairs;

determine a greatest common divisor for each Type 2 power savings class ranked pair, a greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes;

determine a difference between the respective durations for each Type 2 power savings class ranked pair, the greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes;

determine a number of rounds for each selected Type 2 power savings class to complete a cycle for each Type 2 power savings class ranked pair, the greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes;

determine a start time for each Type 2 power savings class ranked pair, the greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes; and

apply the determined start time for each Type 2 power savings class ranked pair.

17. The wireless communication mobile station as in claim 16, wherein the at least one processor, when executing the instruction to determines a start time for each Type 2 power savings class ranked pair, is further configured to, when executing instructions:

align a Type 2 power savings class ranked pair, in which the durations of the two Type 2 power savings classes are equal, by starting the two Type 2 power savings classes of the Type 2 power savings class ranked pair, at the same time;

align the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to a Type 2 power savings class with the shorter duration of the Type 2 power savings class ranked pair, by starting the two Type 2 power savings classes of the Type 2 power savings class ranked pair, at the same time;

align the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to one, a duration of a sleep window of a first Type 2 power savings class is greater than a duration of a sleep window of a second Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the listening window of the second Type 2 power savings class is greater than a duration of the listening window of the first Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having a shorter duration sleep window after the start of the Type 2 power savings class with a longer duration sleep window, at a time equal to a difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair;

align the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to one, a duration of a sleep window of a first Type 2 power savings class is greater than a duration of a sleep window of a second Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the listening window of the first Type 2 power savings class is greater than or equal to the duration of the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to a difference between respective durations of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair;

align the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to one and the duration of a sleep window of the first Type 2 power savings class is less than or equal to the duration of a sleep window of a second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal the difference between the respective durations of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair;

align the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal one or in which the greatest common divisor does not equal the duration of the shorter Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the sleep window of the first Type 2 power savings class is greater than the duration of the sleep window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to an absolute value of a difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair, but if the time equal to the absolute value of the difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair is greater than a listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair;

align the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal one or in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal the duration of the shorter Type 2 power savings class, the duration of the sleep window of the second Type 2 power savings class is greater than the duration of the sleep window of the first Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the listening window of the first Type 2 power savings class is greater than the duration of the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to an absolute value of a difference between the respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair, but if the time equal to the absolute value of the difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair is greater than a listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair; and

align remaining Type 2 power savings class ranked pairs in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal one or in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal the duration of the shorter Type 2 power savings class by starting the Type 2 power savings class with the shorter duration after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to a difference between the respective durations of first and second Type 2 power savings classes of the Type 2 power savings class ranked pair, but if the time equal to the difference between respective durations of first and second Type 2 power savings classes of the Type 2 power savings class ranked pair is greater than a listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at the time equal to the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair.

18. The wireless communication mobile station as in claim 11, wherein the at least one processor, when executing the instruction to align the two or more aligned Type 1 power savings classes or, if only one Type 1 power savings class is selected, the selected Type 1 power savings class, and the two or more aligned Type 2 power savings classes or, if only one Type 2 power savings class is selected, the selected Type 2 power savings class, is further configured to, when executing instructions:

determine an aligned Type 1 power savings class which will be the last to start;

determine an aligned Type 2 power savings class with the shortest duration;

align the determined Type 1 power savings class with the determined Type 2 power savings class if a duration of a sleep window of the determined Type 2 power savings class is greater than a duration of an initial sleep window of the determined Type 1 power savings class and a duration of a listening window of the determined Type 2 power savings class is also greater than a duration of a listening window of the determined Type 1 power savings class, by starting the determined Type 1 power savings class at a time after the determined Type 2 power savings class equal to a difference between respective durations of the determined Type 2 power savings class sleep window and the determined Type 1 power savings class initial sleep window;

align the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 1 power savings class initial sleep window is greater than the duration of the determined Type 2 power savings class sleep window and the duration of the determined Type 1 power savings class listening window is also greater than the duration of the determined Type 2 power savings class listening window, by starting the determined Type 2 power savings class at a time after the determined Type 1 power savings class equal to a difference between the respective durations of the determined Type 1 power savings class initial sleep window and the determined Type 2 power savings class sleep window;

align the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 2 power savings class sleep window is greater than or equal to the duration of the determined Type 1 power savings class initial sleep window and the duration of the determined Type 1 power savings class listening window is also greater than or equal to the duration of the determined Type 2 power savings class listening window, by starting the determined Type 1 power savings class and the determined Type 2 power savings class at the same time;

align the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 2 power savings class sleep window is equal to the duration of the determined Type 1 power savings class initial sleep window and the duration of the determined Type 2 power savings class listening window is greater than the duration of the determined Type 1 power savings class listening window, by starting the determined Type 1 power savings class at a time after the determined Type 2 power savings class equal to an absolute value of a difference between respective durations of the determined Type 2 power savings class and the determined Type 1 power savings class; and

align the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 1 power savings class initial sleep window is greater than the duration of the determined Type 2 power savings class sleep window and the duration of the determined Type 2 power savings class listening window is greater than or equal to the duration of the determined Type 1 power savings class listening window, by starting a determined power savings class with the shorter duration at a time after a determined power savings class with the longer duration equal to the absolute value of the difference between the respective durations of the determined Type 2 power savings class and the determined Type 1 power savings class.

19. The wireless communication mobile station as in claim 11, wherein aligning the selected Type 3 power savings classes with the aligned Type 1 and Type 2 power savings classes includes matching the start time of the Type 3 power savings class with the start time of a last to start Type 1 power savings class or Type 2 power savings class.

20. The wireless communication mobile station as in claim 11, wherein the wireless communications network is compliant with IEEE 802.16e standard.

21. A computer-readable medium including instructions for performing a method, when executed by a processor, for power savings in a wireless communications network, the method comprising:

selecting all Type 1 power savings classes, if present on a device, wherein each of the one or more Type 1 power savings classes has a series of equal fixed duration listening windows alternating with a series of sleep windows, and wherein each sleep window has twice a duration of a previous sleep window, up to a maximum sleep window duration, and an initial sleep window duration is greater than or equal to the listening window fixed duration;

selecting all Type 2 power savings classes, if present on the device, wherein each of the one or more Type 2 power savings classes has a series of equal fixed duration listening windows alternating with a series of equal fixed duration sleep windows and the sleep window duration is greater than the listening window duration;

selecting all Type 3 power savings classes, if present on the device, wherein each of the one or more Type 3 power savings classes has a sleep window wherein durations and separations of an expected time period of activity and the sleep window is set based on an expected arrival of a next portion of data or next expected ranging request;

aligning the selected Type 1 power savings classes of the device, if more than one Type 1 power savings class is selected;

aligning the selected Type 2 power savings classes of the device, if more than one Type 2 power savings class is selected;

aligning the two or more aligned Type 1 power savings classes or, if only one Type 1 power savings class is selected, the selected Type 1 power savings class, and the two or more aligned Type 2 power savings classes or, if only one Type 2 power savings class is selected, the selected Type 2 power savings class, if there is at least one selected Type 1 power savings class and at least one selected Type 2 power savings class;

aligning the selected Type 3 power savings classes with the aligned Type 1 and Type 2 power savings classes, if there is at least one selected Type 3 power savings class and at least one Type 1 or Type 2 power savings class; and

communicating the alignment of any Type 1, Type 2, or Type 3 power savings classes to a base station.

22. The computer-readable medium as in claim 21, wherein the aligning of the selected Type 1 power savings classes further includes:

sorting the selected Type 1 power savings classes in order of increasing duration of initial sleep windows of the selected Type 1 power savings classes to define Type 1 power savings class ranked pairs;

aligning as a Type 1 power savings class twice length pair two Type 1 power savings classes for which the initial sleep window of a first Type 1 power savings class of the Type 1 power savings class twice length pair has twice a duration of the initial sleep window of a second Type 1 power savings class of the Type 1 power savings class twice length pair, the aligning including starting the second Type 1 power savings class at a time equal to the initial sleep window duration of the first Type 1 power savings class plus a duration of a listening window of the first Type 1 power savings class;

aligning two Type 1 power savings classes in the Type 1 power savings class ranked pair, Type 1 power savings class ranked pair by Type 1 power savings class ranked pair, in the sorted order of increasing duration of the initial sleep windows of Type 1 power savings classes, except when the aligning of the Type 1 power savings class ranked pair changes an alignment of any Type 1 power savings class twice length pair, wherein aligning two Type 1 power savings classes in a Type 1 power savings class ranked pair, Type 1 power savings class ranked pair by Type 1 power savings class ranked pair, in the sorted order of Type 1 power savings classes, further includes;

aligning the Type 1 power savings class ranked pair, for which a difference between an initial sleep window of a first Type 1 power savings class and an initial sleep window of a second Type 1 power savings class of the Type 1 power savings class ranked pair is an odd number of frames, by starting the Type 1 power savings class of the Type 1 power savings class ranked pair having a shorter duration initial sleep window after starting of the Type 1 power savings class of the Type 1 power savings class ranked pair having a longer duration initial sleep window, at a time equal to a difference between respective durations of the initial sleep windows of the Type 1 power savings class ranked pair; and

aligning the Type 1 power savings class ranked pair, for which the difference between the initial sleep window of the first Type 1 power savings class and the initial sleep window of the second Type 1 power savings class of the Type 1 power savings class ranked pair is an even number of frames, by starting both Type 1 power savings classes of the Type 1 power savings class ranked pair at the same time.

23. The computer-readable medium as in claim 21, wherein the aligning of the selected Type 2 power savings classes further includes:

sorting the selected Type 2 power savings classes in order of decreasing respective durations of the selected Type 2 power savings classes into Type 2 power savings class ranked pairs;

determining a greatest common divisor for each Type 2 power savings class ranked pair, a greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes;

determining a difference between the respective durations for each Type 2 power savings class ranked pair, the greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes;

determining a number of rounds for each selected Type 2 power savings class to complete a cycle for each Type 2 power savings class ranked pair, the greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes;

determining a start time for each Type 2 power savings class ranked pair, the greater duration Type 2 power savings class with its following Type 2 power savings class, in the sorted order of Type 2 power savings classes, wherein determining a start time for each Type 2 power savings class ranked pair further includes;

aligning a Type 2 power savings class ranked pair, in which the durations of the two Type 2 power savings classes are equal, by starting the two Type 2 power savings classes of the Type 2 power savings class ranked pair, at the same time;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to a Type 2 power savings class with the shorter duration of the Type 2 power savings class ranked pair, by starting the two Type 2 power savings classes of the Type 2 power savings class ranked pair, at the same time;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to one, a duration of a sleep window of a first Type 2 power savings class is greater than a duration of a sleep window of a second Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the listening window of the second Type 2 power savings class is greater than a duration of the listening window of the first Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having a shorter duration sleep window after the start of a Type 2 power savings class with a longer duration sleep window, at a time equal to a difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to one, a duration of a sleep window of a first Type 2 power savings class is greater than a duration of a sleep window of a second Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the listening window of the first Type 2 power savings class is greater than or equal to the duration of the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to a difference between respective durations of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair is equal to one and the duration of a sleep window of the first Type 2 power savings class is less than or equal to the duration of a sleep window of a second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal the difference between the respective durations of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal one or in which the greatest common divisor does not equal the duration of the shorter Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the sleep window of the first Type 2 power savings class is greater than the duration of the sleep window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to an absolute value of a difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair, but if the time equal to the absolute value of the difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair is greater than a listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair;

aligning the Type 2 power savings class ranked pair, in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal one or in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal the duration of the shorter Type 2 power savings class, the duration of the sleep window of the second Type 2 power savings class is greater than the duration of the sleep window of the first Type 2 power savings class of the Type 2 power savings class ranked pair, and the duration of the listening window of the first Type 2 power savings class is greater than the duration of the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, by starting the Type 2 power savings class having the shorter duration after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to an absolute value of a difference between respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair, but if the time equal to the absolute value of the difference between the respective durations of the sleep windows of the first and second Type 2 power savings classes of the Type 2 power savings class ranked pair is greater than a listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair; and

aligning remaining Type 2 power savings class ranked pairs in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal one or in which the greatest common divisor of the Type 2 power savings class ranked pair does not equal the duration of the shorter Type 2 power savings class by starting the Type 2 power savings class with the shorter duration after the start of the Type 2 power savings class with the longer duration sleep window, at a time equal to a difference between the respective durations of first and second Type 2 power savings classes of the Type 2 power savings class ranked pair, but if the time equal to the difference between respective durations of first and second Type 2 power savings classes of the Type 2 power savings class ranked pair is greater than a listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair, starting the Type 2 power savings class having the shorter duration sleep window after the start of the Type 2 power savings class with the longer duration sleep window, at the time equal to the listening window of the second Type 2 power savings class of the Type 2 power savings class ranked pair; and

applying the determined start time for each Type 2 power savings class ranked pair

24. The computer-readable medium as in claim 21, wherein the aligning of the two or more aligned Type 1 power savings classes or, if only one Type 1 power savings class is selected, the selected Type 1 power savings class, and the two or more aligned Type 2 power savings classes or, if only one Type 2 power savings class is selected, the selected Type 2 power savings class, includes:

determining an aligned Type 1 power savings class which will be the last to start;

determining an aligned Type 2 power savings class with the shortest duration;

aligning the determined Type 1 power savings class with the determined Type 2 power savings class if a duration of a sleep window of the determined Type 2 power savings class is greater than a duration of an initial sleep window of the determined Type 1 power savings class and a duration of a listening window of the determined Type 2 power savings class is also greater than a duration of a listening window of the determined Type 1 power savings class, by starting the determined Type 1 power savings class at a time after the determined Type 2 power savings class equal to a difference between respective durations of the determined Type 2 power savings class sleep window and the determined Type 1 power savings class initial sleep window;

aligning the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 1 power savings class initial sleep window is greater than the duration of the determined Type 2 power savings class sleep window and the duration of the determined Type 1 power savings class listening window is also greater than the duration of the determined Type 2 power savings class listening window, by starting the determined Type 2 power savings class at a time after the determined Type 1 power savings class equal to a difference between the respective durations of the determined Type 1 power savings class initial sleep window and the determined Type 2 power savings class sleep window;

aligning the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 2 power savings class sleep window is greater than or equal to the duration of the determined Type 1 power savings class initial sleep window and the duration of the determined Type 1 power savings class listening window is also greater than or equal to the duration of the determined Type 2 power savings class listening window, by starting the determined Type 1 power savings class and the determined Type 2 power savings class at the same time;

aligning the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 2 power savings class sleep window is equal to the duration of the determined Type 1 power savings class initial sleep window and the duration of the determined Type 2 power savings class listening window is greater than the duration of the determined Type 1 power savings class listening window, by starting the determined Type 1 power savings class at a time after the determined Type 2 power savings class equal to an absolute value of a difference between respective durations of the determined Type 2 power savings class and the determined Type 1 power savings class; and

aligning the determined Type 1 power savings class with the determined Type 2 power savings class if the duration of the determined Type 1 power savings class initial sleep window is greater than the duration of the determined Type 2 power savings class sleep window and the duration of the determined Type 2 power savings class listening window is greater than or equal to the duration of the determined Type 1 power savings class listening window, by starting a determined power savings class with the shorter duration at a time after a determined power savings class with the longer duration equal to the absolute value of the difference between the respective durations of the determined Type 2 power savings class and the determined Type 1 power savings class.

25. The computer-readable medium as in claim 21, wherein the aligning of the selected Type 3 power savings classes with the aligned Type 1 and Type 2 power savings classes includes matching the start time of the Type 3 power savings class with the start time of a last to start Type 1 power savings class or Type 2 power savings class.