Apparatus, and associated method, for selecting a switching threshold for a transmitter utilizing adaptive modulation techniques

Apparatus, and an associated method selects an adaptive switching threshold level responsive to a constrained optimization scheme. The switching level is selected by an LRI function forming a portion of a transmitting station, such as a base transceiver station operable in a cellular communication system. The switching threshold level is utilized in the selection by an adaptive modulator of a modulation parameter by which data transmitted by the transmitting station is encoded or modulated.