Patent ID: 8290084
Filing Date: 2012-10-16
Classification: H04B,H04L

Abstract:
1. Transmitter circuitry for a code division multiple access system comprising: A. diversity control circuitry having a Doppler control signal input, a handoff signal input and a control output signal having a first state and a second state; B. a space time transmit diversity circuit having a control input connected with the control output signal of the diversity control circuitry, a symbol input adapted to receive a series of symbol signals, a first antenna output, and a second antenna output, the diversity circuitry, in response to the control output signal being in the first state, alternately connecting the symbol signals on the symbol input to the first antenna output and the second antenna output, and the diversity circuitry, in response to the control output signal being in the second state, effecting space time transmit diversity by producing a symbol on the first antenna output and a transformed symbol on the second antenna output; and C. receiver circuitry receiving signals from mobile units in the same cell as the transmitter circuitry indicating received signal strength from surrounding base stations, and when a base station handoff is required, the control circuitry outputs a control output signal in the second state.