Method for channel allocation utilizing power restrictions

• US 6,259,685 B1
• Filed: 09/03/1999
• Issued: 07/10/2001
• Est. Priority Date: 03/27/1997
• Status: Expired due to Term

• Current Assignee: HMD Global Oy
• Original Assignee: Nokia Telecommunications Oy (Nokia Corporation)
• Inventors: Salonaho, Oscar, Rinne, Mikko, Rinne, Mika
• Primary Examiner(s): Vu, Huy D.
• Assistant Examiner(s): Harper, Kevin C.
• Application Number:
  US09/390,529
• Time in Patent Office: 676 Days
• Field of Search: 370/321, 370/322, 370/326, 370/345, 370/347, 370/348, 370/328, 370/329, 370/330, 370/436, 370/335, 370/342, 455/450, 455/451, 455/452, 455/454
• US Class Current: 370/330
• CPC Class Codes: H04W 16/06 Hybrid resource partitioning, e.g. channel borrowing
• CPC Class Codes: H04W 16/12 Fixed resource partitioning
• CPC Class Codes: H04W 28/16 Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
• CPC Class Codes: H04W 52/283 Power depending on the position of the mobile
• CPC Class Codes: H04W 52/34 TPC management, i.e. sharing limited amount of power among users or channels or data types, e.g. cell loading
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

In channel allocation, the objective is to allocate channels to desired connections using the available frequency spectrum as effectively as possible so that the connections will not cause excessive interference to each other. This invention presents a method based on time blocking of transmission in connections using different transmission powers, in order further to improve the allocation of channels.

Claims

1. A method for channel allocation in a mobile communications system having a time frame structure and including mobile stations, several base transceiver stations and cells defined by their radio coverage areas, whereby a set of channels is allocated for each cell, a set of carrier wave frequencies is allocated for use by each cell, a connection can be set up between a mobile station in the cell and a base transceiver station of the cell using a channel which uses some carrier wave frequency allocated for use by the cell and which is defined at least by a time slot in the time frame structure, and wherein transmission powers used by mobile stations and base transceiver stations can be adjusted, a maximum transmission power permissible on a channel being predetermined, said method comprising:

allocating the carrier wave frequencies with a relatively dense reuse pattern;

dividing cells using the same carrier wave frequencies into classes;

in each class, allocating channels to cells belonging to the same class so that connections using the same channel simultaneously in different cells of the same class at the maximum transmission power would cause mutual interference to each other exceeding acceptable interference; and

subsequently

in each class, adjusting transmission powers of cells belonging to the same class and using the same channel on a time slot basis, so that, concerning each time slot, a transmission at the maximum transmission power is allowed only in one cell, and adjusting transmission powers of for each cell belonging to the same class to have an individual time slot basis transmission power limitation.

2. The method as defined in claim 1, wherein:

the connections of the cell are arranged according to the required transmission power from the highest to the lowest; and

time slots are allocated to the connections arranged according to the transmission power in an order of magnitude of the permissible transmission powers of the time slots.

3. The method as defined in claim 1, wherein the channel is defined by the time slot of the time frame and by frequency.

4. The method as defined in claim 1, wherein the channel is defined by the time slot of the time frame and by a hash code.

5. The method as defined in claim 1, wherein the channel is defined by the time slot of the time frame, frequency, and by a hash code.

6. The method as defined in claim 1, wherein the transmission power limitations are changed dynamically according to the network load situation.

7. The method as defined in claim 1, wherein the same transmission power limitation is established for the time slot at all carrier wave frequencies.

8. The method as defined in claim 1, wherein a different transmission power limitation is established for the time slot at different carrier wave frequencies of the cell.

9. The method as defined in claim 1, wherein the transmission power limitations of the time slots are independent of each other in the direction from mobile station to base transceiver station and in the direction from base transceiver station to mobile station.

10. The method as defined in claim 1 in a system wherein an information signal to be transferred between a mobile station and a base transceiver station is processed to make the information signal better tolerate transfer errors on the radio path, whereby different requirements on the signal transmission power are achieved with different processing methods,

wherein:

the transmission power required by the connection is reduced by beginning to use a processing method achieving a tolerance of transfer errors on the radio path which is better than the original tolerance; and

the signal having a better tolerance of transfer errors on the radio path is placed in a time slot, wherein the maximum transmission power is lower than the transmission power required by a signal processed with the original processing method.

11. The method as defined in claim 10, wherein, in addition, several information signals with different tolerances of transfer errors are transferred, wherein the signals are allocated in time slots according to their tolerance of transfer errors, so that a lower tolerance of transfer errors corresponds to a higher transmission power permitted in the time slot.

12. A method for channel allocation in a mobile communications system with a time frame structure and including mobile stations, several base transceiver stations, and cells defined by their radio coverage areas, whereby a set of channels is allocated to each cell, a set of carrier wave frequencies is allocated for use by each cell along with channels using the set of carrier wave frequencies according to a certain channel reuse pattern, a connection can be set up between a mobile station in the cell and the base transceiver station of the cell by using a channel using some carrier wave frequency allocated for use by the cell, which channel is defined by at least a time slot in the time frame, and wherein the transmission powers used by mobile stations and base transceiver stations can be adjusted, said method comprising:

dividing transmission powers into at least two transmission power classes, wherein each class includes cells which use the same carrier wave frequency and wherein a common transmission power limitation for a class and maximum transmission power permissible in the class are predetermined;

dividing time slots between the different transmission power classes;

using different channel reuse patterns in the different time slots dependent on the transmission power class used in the time slots;

instructing connections to use the time slots of the transmission power class having the transmission power required for the connection; and

inside transmission power classes in different cells, establishing transmission power limitations stricter than the common transmission power limitation of the class at least for some time slots, in such a way that use of the maximum transmission power permissible in the class is not permitted simultaneously in those cells where connections using the same time slot cause most interference to each other when using the maximum transmission power permissible in the class.

13. The method as defined in claim 12, wherein:

dividing connections into transmission power classes formed according to the required transmission powers; and

instructing the connections divided into each transmission power class to use the time slots of the transmission power class in question.

14. The method as defined in claim 12, wherein the transmission power limitations of time slots are independent of each other in the direction from mobile station to base transceiver station and in the direction from base transceiver station to mobile station.

15. The method as defined in claim 12, wherein the channel is defined by the time slot of the time frame and by frequency.

16. The method as defined in claim 12, wherein the channel is defined by the time slot of the time frame and by a hash code.

17. The method as defined in claim 12, wherein the channel is defined by the time slot of the time frame, frequency, and by a hash code.

18. The method as defined in claim 12, wherein the transmission power limitations are changed dynamically according to the network load situation.

19. The method as defined in claim 12, wherein the time slots are divided between different transmission power classes in the same manner at all carrier wave frequencies.

20. The method as defined in claim 12, wherein the time slots are divided between different transmission power classes in different ways at different carrier wave frequencies.

21. The method as defined in claim 12 in a system wherein;

an information signal to be transferred between a mobile station and a base transceiver station is processed to make the information signal better tolerate transfer errors on the radio path, whereby different requirements on the transmission power of the signal are achieved with different processing methods;

the transmission power required by the connection is reduced by beginning to use a processing method achieving a tolerance of transfer errors on the radio path which is better than the original tolerance; and

the signal having a better tolerance of transfer errors on the radio path is placed in a time slot wherein the maximum transmission power permissible in a class is lower than the transmission power required by a signal processed with the original processing method.

22. The method as defined in claim 21, wherein, in addition, several such information signals are transferred which have different tolerances of transfer errors, wherein the signals are placed in time slots according to their tolerance of transfer errors in such a way that a lower tolerance of transfer errors corresponds to a higher transmission power permitted in the time slot.