SQUARE LAW EXTENSION TECHNIQUE FOR HIGH SPEED RADIO DETECTION

1 . A square law extension circuit operating over a range of frequencies and power levels, comprising:

a detector having an input for receiving radio frequency (RF) signals and providing a detected signal output;

an amplifier having an input that receives the detected signal output and providing an output for an amplified detected signal; and

an expander having an input that receives the amplified detected signal and is arranged to provide an expanded signal output, wherein the expanded signal output is a signal that increases in a first proportion to the amplified detected signal up to a predetermined threshold and increases at a second proportion to the amplified detected signal that is more than the first proportion when the expanded signal output exceeds the predetermined threshold.

2 . The square law extension circuit of claim 1 , wherein the expanded signal output increases linearly with respect to the detected signal output up to the predetermined threshold.

3 . The square law extension circuit of claim 1 , wherein the first proportion indicates square law behavior of the expanded signal output and the second proportion corrects for a deviation from square law behavior of the expanded signal output.

4 . The square law extension circuit of claim 1 , wherein the RF signals applied to the detector operates in a frequency range between 1 MHz and 100 GHz.

5 . The square law extension circuit of claim 1 , wherein the detected signal output includes a power range of at least 2 orders of magnitude.

6 . The square law extension circuit of claim 5 , wherein an expanded output power associated with the expanded signal output extends over a range of at least 4 orders of magnitude.

7 . The square law extension circuit of claim 1 , wherein the expander includes a first resistor, a diode electrically connected in parallel with the first resistor, and a second resistor electrically connected in series with the first resistor and the diode, and wherein the first resistor and the second resistor form a voltage divider.

8 . A method of measuring power in a multiple radio frequency signal environment over a wide range of frequencies and power levels, comprising:

detecting radio frequency power in the multiple radio frequency signal environment;

amplifying a detected voltage output of the radio frequency power to create an amplified voltage output having a predetermined gain;

expanding the amplified voltage output by causing an expanded output signal to increase in a first proportion to the amplified voltage output up to a predetermined threshold and increase at a second proportion to the amplified voltage output that is more than the first proportion when the expanded output signal exceeds the predetermined threshold.

9 . The method of claim 8 , wherein the multiple radio frequency environment includes a first signal having a first power level and a second signal having a second power level that is lower than the first power level.

10 . The method of claim 9 , wherein the second signal includes a pulsed signal.

11 . The method of claim 9 , wherein the second power level is lower than the first power level by at least 2 orders of magnitude.

12 . The method of claim 8 , wherein the first proportion indicates square law behavior of the expanded output signal and the second proportion indicates a correction for a deviation from square law behavior of the expanded output signal.

13 . The method of claim 8 , wherein amplifying a voltage output of the detected radio frequency power is performed by a high-speed, low-noise direct current coupled amplifier.

14 . The method of claim 8 , wherein the low level of the radio frequency power is defined at −13 dBm or less.

15 . A square law extension circuit operating over a range of frequencies and power levels, comprising:

a detector having an input for receiving radio frequency (RF) signals and providing a detected RF signal output;

an amplifier having an input that receives the detected RF signal and providing an output for an amplified detected RF signal; and

an expander having an input that receives the amplified detected RF signal and providing an expanded signal output, wherein the expander includes a first resistor, a diode electrically connected in parallel with the first resistor, and a second resistor electrically connected in series with the first resistor and the diode, and wherein the first resistor and the second resistor form a voltage divider,

wherein increasing power applied to the detector input causes a voltage drop across the first resistor to increase, and wherein when a voltage drop across the first resistor reaches a first threshold voltage, the first diode receives current and the voltage drop across the first resistor remains at the first threshold voltage while a voltage drop across the second resistor increases.

16 . The square law extension circuit of claim 15 , wherein the power applied to the detector operates in a frequency range between 1 MHz and 100 GHz.

17 . The square law extension circuit of claim 15 , wherein the video amplifier defines a gain that is set so the diode starts conducting current when the detected output signal begins deviating from square law behavior.

18 . The square law extension circuit of claim 15 , wherein the voltage divider reduces the expanded signal output by a proportion equal to the gain necessary to correct for the square law deviation.

19 . The square law extension circuit of claim 15 , wherein the expander diode includes a Schottky diode.

20 . The square law extension circuit of claim 15 , wherein the first threshold voltage is approximately 0.4V.