Methods for making active channel measurements in a personal base station environment

• US 5,726,981 A
• Filed: 12/21/1995
• Issued: 03/10/1998
• Est. Priority Date: 12/21/1995
• Status: Expired due to Term

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Mobile Phones UK Limited (Nokia Corporation)
• Inventors: Ylitervo, Matti Kalle Aukusti, Vayrynen, Mika J.
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): HYUN, SOON D
• Application Number:
  US08/576,788
• Time in Patent Office: 810 Days
• Field of Search: 370/252, 370/277, 370/278, 370/332, 370/337, 370/310, 375/224, 375/227, 375/351, 379/58, 379/59, 379/60, 379/61, 379/62, 379/63, 455/9, 455/33.1, 455/33.2, 455/34.1, 455/67.1, 455/226.1, 455/226.2
• US Class Current: 370/332
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 52/0245 according to signal strength
• CPC Class Codes: H04W 84/105 PBS [Private Base Station] network H04W84/12 - H04W84/16 take precedence
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A wireless communications system (1) has at least one base station, such as a personal base station (5), and a plurality of mobile stations (10) capable of wireless slotted communications with the at least one personal base station. A method includes a step of periodically deactivating, for a predetermined period of time, a base station transmitter (32) from transmitting a RF signal to at least one MS. A next step, executed during the predetermined period of time, operates a base station receiver (34) to perform a received signal strength (RSS) measurement. In a first embodiment of this invention the step of deactivating includes a preliminary step of reserving a reverse slot for use by the base station, thereby insuring that a mobile station will not transmit during the reserved slot. In this case the RSS measurement occurs during the reserved slot. In a second embodiment of this invention the step of deactivating includes an initial step of transmitting at least a synchronizing data pattern during the predetermined interval before disabling the transmitter, thereby enabling a mobile station to maintain synchronization with the base station even through the transmitter is switched off.

Claims

1. A method of operating a wireless communications system having at least one base station and at least one mobile station capable of wireless communications with the at least one base station, comprising the steps of:

periodically deactivating, for a predetermined period of time following a transmission of a synchronizing data pattern, a base station transmitter from transmitting a RF signal to the at least one mobile station; and

during the predetermined period of time, operating a base station receiver to perform a received signal strength measurement.

2. A method as set forth in claim 1, wherein the base station transmits and receives signals comprising repeating frames each consisting of a plurality of slots, and wherein the predetermined period of time corresponds to a duration of time that is less than a duration of one slot.

3. A method as set forth in claim 2, wherein the step of deactivating includes a preliminary step of reserving a reverse slot for use by the base station, thereby insuring that no mobile station will transmit during the reserved reverse slot, and wherein the step of operating occurs during the reserved reverse slot.

4. A method as set forth in claim 2, wherein the step of deactivating includes an initial step of transmitting at least the synchronizing data pattern at the beginning of a slot before disabling the transmitter.

5. A method of operating a wireless time division, multiple access communications system having at least one base station for transmitting, to at least one mobile station, a forward RF signal comprised of slotted control and traffic channels and for receiving, from the at least one mobile station, a reverse RF signal comprised of slotted control and traffic channels, wherein at least one forward traffic channel slot is aligned in time with a reverse control slot, comprising the steps of:

prior to a time when the base station is not required to transmit on the at least one forward traffic channel slot, reserving for the exclusive use of the base station the time aligned reverse control slot;

deactivating a base station transmitter from transmitting a RF signal on the at least one forward traffic channel slot; and

during at least a portion of the reserved, time aligned reverse control slot, operating a base station receiver to perform a received signal strength measurement.

6. A method as set forth in claim 5, wherein the step of reserving reserves a random access channel subchannel for exclusive use by the base station, the random access channel subchannel being normally used by the at least one mobile station to request access to the system.

7. A method as set forth in claim 5, wherein the step of deactivating the base station transmitter includes a preliminary step of transmitting at least a synchronizing data pattern on the at least one forward traffic channel slot.

8. A method as set forth in claim 5, wherein the base station forms a portion of a non-public wireless communications system.

9. A method as set forth in claim 8, wherein the step of performing a received signal strength measurement attempts to measure a RF signal received from a public wireless communications system so as to determine if an interference condition exists between the non-public and the public wireless communications systems.

10. A method of operating a wireless time division, multiple access communications system having at least one base station for transmitting, to at least one mobile station, a forward RF signal comprised of slotted control and traffic channels and for receiving, from the at least one mobile station, a reverse RF signal comprised of slotted control and traffic channels, each slot comprising a synchronizing portion, comprising the steps of:

transmitting from the base station at least the synchronizing portion of a slot;

deactivating a base station transmitter after transmitting at least the synchronizing portion; and

during a remainder of the slot, operating a base station receiver to perform a received signal strength measurement.

11. A method as set forth in claim 10, wherein the base station forms a portion of a non-public wireless communications system.

12. A method as set forth in claim 11, wherein the step of performing a received signal strength measurement attempts to measure a RF signal received from a public wireless communications system so as to determine if an interference condition exists between the non-public and the public wireless communications systems.

13. A method as set forth in claim 10 wherein the step of transmitting from the base station at least the synchronizing portion of a slot transmits at least the synchronizing portion of a digital control channel slot.

14. A wireless communications system having at least one base station and at least one mobile station capable of wireless communications with the at least one base station, said base station comprising:

means for periodically deactivating, for a predetermined period of time, a base station transmitter from transmitting a RF signal to the at least one mobile station;

means for transmitting at least a synchronizing data pattern before said deactivating means deactivates said transmitter; and

means for operating, during the predetermined period of time, a base station receiver to perform a received signal strength measurement.

15. A system as set forth in claim 14, wherein the base station transmits and receives signals comprising repeating frames each consisting of a plurality of slots, and wherein the predetermined period of time corresponds to a duration of time that is less than a duration of one slot.

16. A system as set forth in claim 15, wherein said base station further comprises means for reserving a reverse slot for use by the base station, wherein said at least one mobile station is responsive to the slot being reserved for not transmitting during the reserved slot, and wherein said means for operating operates during the reserved slot.

17. A wireless time division, multiple access communications system having at least one base station for transmitting, to at least one mobile station, a forward RF signal comprised of slotted control and traffic channels and for receiving, from the at least one mobile station, a reverse RF signal comprised of slotted control and traffic channels, wherein at least one forward traffic channel slot is aligned in time with a reverse control slot, said system further comprising:

means, operable prior to a time when the base station is not required to transmit on the at least one forward traffic channel slot, for reserving for the exclusive use of the base station the time aligned reverse control slot;

means for deactivating a base station transmitter from transmitting a RF signal on the at least one forward traffic channel slot; and

means, operable during at least a portion of the reserved, time aligned reverse control slot, for operating a base station receiver to perform a received signal strength measurement.

18. A system as set forth in claim 17, wherein said reserving means reserves a random access channel subchannel for exclusive use by the base station, the random access channel subchannel being normally used by the at least one mobile station to request access to the system.

19. A system as set forth in claim 17, and further comprising means for transmitting at least a synchronizing data pattern on the at least one forward traffic channel slot prior to an operation of said deactivating means.

20. A system as set forth in claim 17, wherein the base station forms a portion of a non-public wireless communications system.

21. A system as set forth in claim 20, wherein said base station receiver operating means attempts to measure a RF signal received from a public wireless communications system so as to determine if an interference condition exists between the non-public and the public wireless communications systems.