Method and apparatus for assigning use of a radio frequency communication resource

• US 6,570,861 B1
• Filed: 11/20/1998
• Issued: 05/27/2003
• Est. Priority Date: 11/20/1998
• Status: Expired due to Term

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Chinitz, Leigh M., Marsan, Mark J.
• Primary Examiner(s): Ton, Dang
• Assistant Examiner(s): Boakye, Alexander O.
• Application Number:
  US09/196,996
• Time in Patent Office: 1,649 Days
• Field of Search: 370/332, 370/337, 370/322, 370/347, 370/349, 370/321, 370/331, 370/508, 370/280, 370/329, 370/330, 370/343, 370/344, 370/345, 370/348, 455/509, 455/443, 455/62, 455/450, 455/452, 455/436, 455/438, 455/439, 455/513
• US Class Current: 370/330
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

A radio communication system assigns use of a radio frequency communication resource comprising multiple communication channels in a way that minimizes the likelihood that a weakly received signal will be interfered with by a strongly received signal in an adjacent communication channel. The communication system determines a signal strength of a signal received from a user of the communication resource and, based on the signal strength determination, assigns the user one or more of the communication channels that are then available.

Claims

1. A method of assigning use of a radio frequency communication resource comprising a plurality of communication channels, the method comprising the steps of:

receiving a request for use of the communication resource;

determining a signal strength of the request;

assigning at least one communication channel of the plurality of communication channels based on the signal strength determination;

wherein the step of assigning comprises the steps of;

comparing the signal strength of the request to at least one signal strength threshold; and

assigning a first communication channel of the plurality of communication channels when the signal strength of the request is less than the at least one signal strength threshold and assigning a second communication channel of the plurality of communication channels when the signal strength of the request is greater than or equal to the at least one signal strength threshold, wherein the first communication channel of the plurality of communication channels is different than the second communication channel of the plurality of communication channels, wherein the radio frequency communication resource comprises a plurality of frequency channels, each frequency channel of the plurality of frequency channels comprises a plurality of time slots, and a communication channel comprises one time slot of the plurality of time slots of one frequency channel of the plurality of frequency channels, wherein a set of time slots comprises all time slots concurrently transmitted in the plurality of frequency channels, wherein the first communication channel is contained in a first set of time slots and the second communication channel is contained in a second set of time slots, wherein the first set of time slots is designated for a request of a signal strength less than the at least one signal strength threshold and the second set of time slots is designated for a request of a signal strength greater than or equal to the at least one signal strength threshold, and wherein the first set of time slots is different than the second set of time slots.

2. The method of claim 1, further including the steps of:

when no time slot is available in the set of time slots designated for a request of a designated signal strength and at least one time slot is available in at least one alternate set of time slots, determining a frequency separation between each time slot of the at least one available time slot and a nearest in frequency, occupied time slot in the same set of time slots; and

assigning a time slot in the at least one alternate set of time slots based on the frequency separation determination.

3. The method of claim 2, further including the step of:

when two or more time slots of the at least one available time slot in the at least one alternate set of time slots are determined to be equi-distant, in frequency, from occupied time slots nearest to each time slot of the two or more time slots, determining a level of signal interference in each time slot of the two or more time slots; and

wherein the step of assigning a time slot in the at least one alternate set of time slots is based on the frequency separation determination and the level of signal interference determination.

4. The method of claim 1, wherein the step of assigning comprises the steps of:

comparing the signal strength of the request to at least two signal strength thresholds to produce a comparison;

assigning a first communication channel of the plurality of communication channels when the signal strength of the request is less than the at least two signal strength thresholds;

assigning a second communication channel of the plurality of communication channels when the signal strength of the request is greater than or equal to a first signal strength threshold of the at least two signal strength thresholds and less than a second signal strength threshold of the at least two signal strength thresholds;

assigning a third communication channel of the plurality of communication channels when the signal strength of the request is greater than or equal to the at least two signal strength thresholds; and

wherein the first communication channel of the plurality of communication channels, the second communication channel of the plurality of communication channels, and the third communication channel of the plurality of communication channels are each a different communication channel and the first signal strength threshold is different than the second signal strength threshold.

5. A method of assigning use of a radio frequency communication resource comprising a plurality of communication channels, the method comprising the steps of:

receiving a request for use of the communication resource;

determining a signal strength of the request; and

assigning at least one communication channel of the plurality of communication channels based on the signal strength determination;

when at least one communication channel is assigned and is occupied by a signal, monitoring the signal strength of the signal occupying the at least one assigned communication channel to produce a plurality of signal strength measurements;

comparing each signal strength measurement of the plurality of signal strength measurements to the at least one signal strength threshold to produce a plurality of signal strength measurement comparisons; and

reassigning the signal occupying the at least one assigned communication channel to a different communication channel of the plurality of communication channels in response to undesirable variations in the plurality of signal strength measurement comparisons.

6. A method of assigning use of a radio frequency communication resource by a communication device, wherein the radio frequency communication resource comprises a plurality of frequency channels, each frequency channel of the plurality of frequency channels comprises a plurality of time slots, and a communication channel comprises one time slot of the plurality of time slots of one frequency channel of the plurality of frequency channels, the method comprising the steps of:

receiving a signal transmitted by the communication device to produce a received signal;

determining a signal strength of the received signal;

comparing the signal strength of the received signal to at least one signal strength threshold to produce a comparison;

assigning a first communication channel of the plurality of communication channels when the signal strength of the received signal is less than the at least one signal strength threshold and assigning a second communication channel of the plurality of communication channels when the signal strength of the received signal is greater than or equal to the at least one signal strength threshold;

wherein a set of time slots comprises all time slots concurrently transmitted in the plurality of frequency channels;

wherein the first communication channel is contained in a first set of time slots and the second communication channel is contained in a second set of time slots;

wherein the first set of time slots is designated for a received signal of a signal strength less than the at least one signal strength threshold and the second set of time slots is designated for a received signal of a signal strength greater than or equal to the at least one signal strength threshold; and

wherein the first set of time slots is different than the second set of time slots.

7. The method of claim 6, further including the steps of:

when no time slot is available in the set of time slots designated for a received signal of a designated signal strength and at least one time slot is available in at least one alternate set of time slots, determining a frequency separation between each time slot of the at least one available time slot and a nearest, in frequency, occupied time slot in the same set of time slots; and

assigning a time slot in the at least one alternate set of time slots is based on the frequency separation determination.

8. The method of claim 7, further including the step of:

when two or more time slots of the at least one available time slot in the at least one alternate set of time slots are determined to be equi-distant, in frequency, from occupied time slots nearest to each time slot of the two or more time slots, determining a level of signal interference in each time slot of the two or more time slots; and

wherein the step of assigning a time slot in the at least one alternate set of time slots is based on the frequency separation determination and the level of signal interference determination.

9. The method of claim 6, wherein the at least one signal strength threshold comprises a first signal strength threshold and a second signal strength threshold, wherein the step of comparing comprises comparing the signal strength of the received signal to the first signal strength threshold and to the second signal strength threshold, and wherein the step of assigning comprises the steps of:

assigning a first communication channel of the plurality of communication channels when the signal strength of the received signal is less than both the first signal strength threshold and the second signal strength threshold;

assigning a second communication channel of the plurality of communication channels when the signal strength of received signal is greater than or equal to the first signal strength threshold and less than the second signal strength threshold;

assigning a third communication channel of the plurality of communication channels when the signal strength of the received signal is greater than or equal to both the first signal strength threshold and the second signal strength threshold;

wherein the first signal strength threshold is different than the second signal strength threshold;

wherein the first communication channel is contained in a first set of time slots, the second communication channel is contained in a second set of time slots, and the third communication channel is contained in a third set of time slots;

wherein the first set of time slots is designated for a received signal of a signal strength less than both the first signal strength threshold and the second signal strength threshold, the second set of time slots is designated for a received signal of a signal strength greater than or equal to the first signal strength threshold and less than the second signal strength threshold, and the third set of time slots is designated for a received signal of a signal strength greater than or equal to both the first signal strength threshold and the second signal strength threshold; and

wherein the first set of time slots, the second set of time slots, and the third set of time slots are different sets of time slots.

10. The method of claim 6, wherein the method further comprises the steps of:

when at least one communication channel is assigned and is occupied by a signal, monitoring the signal strength of the signal occupying the at least one assigned communication channel to produce a plurality of signal strength measurements;

comparing each signal strength measurement of the plurality of signal strength measurements to the at least one signal strength threshold to produce a plurality of signal strength measurement comparisons; and

reassigning the signal occupying the at least one assigned communication channel to a different communication channel of the plurality of communication channels in response to undesirable variations in the plurality of signal strength measurement comparisons.

11. A communication system for assigning use of a radio frequency communication resource comprising:

a receiver to receive a radio frequency signal;

a transmitter;

a processor coupled to the receiver and the transmitter, wherein the processor determines a signal strength of the radio frequency signal and assigns use of the radio frequency communication resource based on the signal strength determination;

wherein the radio frequency signal comprises a request for use of the radio frequency communication resource;

wherein the processor monitors a signal strength of a signal using the communication resource and compares the signal strength of the monitored signal to at least one signal strength threshold;

wherein the processor reassigns the use of the radio frequency communication resource by the monitored signal based on the comparison of the signal strength of the monitored signal to the at least one signal strength threshold;

wherein the radio frequency communication resource comprises a plurality of frequency channels, each frequency channel of the plurality of frequency channels comprises a plurality of time slots, and a communication channel comprises one time slot of the plurality of time slots of one frequency channel of the plurality of frequency channels;

wherein a set of time slots comprises all time slots concurrently transmitted in the plurality of frequency channels;

wherein the first communication channel is contained in a first set of time slots and the second communication channel is contained in a second set of time slots;

wherein the first set of time slots is designated for a request of a signal strength less than the at least one signal strength threshold and the second set of time slots is designated for a request of a signal strength greater than or equal to the at least one signal strength threshold; and

wherein the first set of time slots is different than the second set of time slots.