Method and apparatus for enhancing an operating characteristic of a radio transmitter

A radio transmitter that includes a power amplifier and an antenna for radiating an information bearing signal, the, radio transmitter operating in an environment of varying antenna loads, the radio transmitter comprising:

• a variable output matching network of the power amplifier;
• sampling means, operably coupled to an output of the variable output matching network and the antenna, for sampling a forward component of the information bearing signal to produce a sampled forward component and a reflected component of the information bearing signal to produce a sampled reflected component;
• signal processing means, operably coupled to the sampling means, for processing the sampled forward component and the sampled reflected component to produce a control signal;
• and
• feedback means, disposed between the signal processing means and the variable output matching network, for coupling the control signal to the variable output matching network to compensate for the varying antenna loads.

In a radio transmitter that includes a power amplifier and an antenna, a method for enhancing an operating characteristic of the radio transmitter in an environment of varying antenna loads, the method comprising the steps of:

• A) providing a plurality of time division multiple access (TDMA) time frames, each of the plurality of TDMA time frames including a plurality of information bearing time slots and a plurality of non-information bearing time slots, at least one of the plurality of information bearing time slots being partitioned into a training portion and an information portion to produce at least one partitioned information bearing time slot, wherein the plurality of information bearing time slots comprise energy to be radiated by the antenna;
• B) coupling, by a variable output matching network of the power amplifier, the plurality of TDMA time frames to a sampler that is operably coupled to an output of the variable output matching network and the antenna;
• C) sampling, by the sampler, a forward component of the at least one partitioned information bearing time slot at a time substantially within the training portion to produce a sampled forward component;
• D) sampling, by the sampler, a reflected component of the at least one partitioned information bearing time slot at a time substantially within the training portion to produce a sampled reflected component;
• E) processing the sampled forward component and the sampled reflected component to produce a feedback control signal;
• and
• F) conveying the feedback control signal to the variable output matching network at a time corresponding to the plurality of non-information bearing time slots to adjust the variable output matching network to compensate for the varying antenna loads.