System and method for temperature compensation of external antenna units

Abstract

A system and method for controlling transmitted output power of autonomous hand held devices and external antenna units. Transmit power of an information signal is controlled in the hand held device utilizing multiple units for transmission. The transmit power is controlled by obtaining a temperature compensated power measurement of the information signal transmitting from the antenna unit. The temperature compensated power measurement is determined by either a software or a hardware compensation scheme. The software temperature compensation scheme involves identifying a power detector output and temperature output within the antenna unit and sending both outputs through a power estimator, where the power estimator utilizes voltage-temperature correlation equations, to produce the temperature compensated power measurement. The hardware temperature compensation scheme involves the use of a temperature compensation circuit made up of a diode pair, an amplifier, a negative temperature coefficient thermistor, and a positive temperature coefficient thermistor. The diode pair is used to provide a true average of the current power input and sends its output to the amplifier. The amplifier produces the temperature compensated power measurement, where the negative temperature coefficient thermistor increases the temperature compensated power measurement at low temperatures and the positive temperature coefficient thermistor increases the temperature compensated power measurement at high temperatures. The temperature compensated power measurement is used by the hand held device to adjust the power of the transmitted information signal.

Dependencies are inferred from the claim text.