Apparatus and method of controlling transmitting power in a subscriber of a wireless telecommunications system

Abstract

A wireless telecommunications systems (,) includes a central terminal (,) for transmitting and receiving radio frequency signals to and from a subscriber terminal (,). A downlink communication path is established from a transmitter (,) of the central terminal (,) to a receiver (,) of the subscriber terminal (,). A downlink signal (,) is transmitter from the transmitter (,) to the receiver (,) during setup and operation of the wireless telecommunications system (,). The receiver (,) of the subscriber terminal (,) compares a code and phase of a master code sequence in the downlink signal (,) to a code and phase of a slave code sequence of the receiver (,). The receiver (,) adjusts the phase of the slave code sequence until a match is obtained with the master code sequence. The downlink signal (,) includes an overhead channel (,) having a power control signal (,), a code synchronization signal (,), and a frame alignment signal (,). The power control signal (,) is capable of adjusting a transmitting power of a transmitter (,) in the subscriber terminal (,). The code synchronization signal (,) is capable of adjusting a phase of a transmitter (,) in the subscriber terminal (,). A receiver (,) in the central terminal (,) monitors an uplink signal (,) transmitted by the transmitter (,) in the subscriber terminal and provides changes to the code synchronization signal (,) such that the transmitter (,) is synchronized to the receiver (,). The receiver (,) monitors the downlink signal (,) to identify the frame alignment signal (,) and establishes the downlink communication path when two successive frame alignment signals (,) are identified. The wireless telecommunications system (,) operates in one of three operating modes. In an acquisition mode during establishment of the downlink communication path, the downlink signal (,) is transmitted at a high power level and a low transmit rate with the receiver (,) operating at the low transmit rate. In a standby mode after establishment of the downlink communication path, the downlink signal (,) is transmitted at a low power level and a low transmit rate with the receiver (,) operating at the low transmit rate. In a traffic mode upon a request for wireless communication transmission, the downlink signal (,) is transmitted at a high power level and a high transmit rate with the receiver (,) adjusting to operate at the high transmit rate. Upon completion of the wireless communication transmission, the wireless telecommunications system (,) returns to the standby mode and the receiver (,) adjusts to operate at the low transmit rate.