초록 ▼

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 temperatur

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.

대표청구항 ▼

1. A temperature compensation circuit for obtaining a temperature compensated power measurement of an information signal from an antenna unit, comprising:an impedance matching circuit, wherein said impedance matching circuit receives a power input and produces an impedance matching circuit output; a

1. A temperature compensation circuit for obtaining a temperature compensated power measurement of an information signal from an antenna unit, comprising:an impedance matching circuit, wherein said impedance matching circuit receives a power input and produces an impedance matching circuit output; a capacitor coupled to said impedance matching circuit, wherein said capacitor receives said impedance matching circuit output to introduce capacitance into said impedance matching circuit output as required; a diode pair coupled to said capacitor for producing an output which is a true average of detected output power from the antenna unit; an amplifier coupled to said diode pair, wherein said amplifier receives said diode pair output and produces the temperature compensated power measurement; a negative temperature coefficient thermistor coupled to said amplifier, wherein said negative temperature coefficient thermistor increases the temperature compensated power measurement at low temperatures; and a positive temperature coefficient thermistor coupled to said amplifier, wherein said positive temperature coefficient thermistor increases the temperature compensated power measurement output at high temperatures.