Wireless device having fast-receive mode for measuring received signal strength (rssi) for higher time division multiple access (tdma) multislot classes

Abstract

A wireless communications device having a fast-receive mode for measuring received signal strength indication (RSSI) enables the device to handle higher time division multiple access (TDMA) multislot classes without requiring that the device include either a second receiver or a receiver with a more advanced and expensive phase-locked loop (PLL) design. The time to complete an RSSI measurement is reduced by initiating the sampling of signal strength before the radio transceiver is fully stabilized in the downlink mode. By initiating sampling before PLL stabilization is complete, the overall time to complete an RSSI measurement is reduced sufficiently to enable scheduling of an RSSI measurement in each GSM frame.

1 . A wireless communications device for obtaining a received signal strength indication (RSSI) measurement, the device comprising:
 a TDMA radio transceiver operable in at least two modes comprising a normal mode and a fast receive mode,   wherein the TDMA radio transceiver initiates collection of RSSI signal samples prior to complete stabilization of phase-locked loop (PLL).   
     
     
         2 . The wireless communications device of  claim 1 , wherein the TDMA radio transceiver further initiates PLL stabilization at least partially in parallel with the collection of RSSI signal samples, whereby time required for completion of collection of RSSI signal samples fits in one of a plurality of timeslots of a frame. 
     
     
         3 . The wireless communications device of  claim 1 , wherein the TDMA radio transceiver completes the collection of the RSSI signal without being on-frequency for the duration of the sampling. 
     
     
         4 . A method of obtaining a received signal strength indication (RSSI) measurement from a wireless device, the method comprising:
 operating a TDMA radio transceiver in at least two modes comprising a normal mode and a fast receive mode; and   initiating collection of RSSI signal samples by the TDMA radio transceiver prior to complete stabilization of phase-locked loop (PLL).   
     
     
         5 . The method  claim 4 , further comprising:
 initiating PLL stabilization at least partially in parallel with the collection of RSSI signal samples, whereby time required for completion of collection of RSSI signal samples fits in one of a plurality of timeslots of a frame.   
     
     
         6 . The method of  claim 4 , further comprising:
 completing the collection of the RSSI signal without being on-frequency for the duration of the sampling.   
     
     
         7 . A non-transitory computer readable medium comprising code which, when loaded into memory and executed on a processor of a wireless communications device comprising a TDMA radio transceiver, is configured to obtain a received signal strength indication (RSSI) measurement by:
 operating the TDMA radio transceiver in at least two modes comprising a normal mode and a fast receive mode; and   initiating collection of RSSI signal samples by the TDMA radio transceiver prior to complete stabilization of phase-locked loop (PLL).   
     
     
         8 . The computer readable medium  claim 7 , further comprising:
 initiating PLL stabilization at least partially in parallel with the collection of RSSI signal samples, whereby time required for completion of collection of RSSI signal samples fits in one of a plurality of timeslots of a frame.   
     
     
         9 . The computer readable medium of  claim 7 , further comprising:
 completing the collection of the RSSI signal without being on-frequency for the duration of the sampling.