Full-wave receiver architecture for the homodyne motion sensor
A homodyne motion sensor or detector based on ultra-wideband radar utilizes the entire received waveform through implementation of a voltage boosting receiver. The receiver includes a receiver input and a receiver output. A first diode is connected to the receiver output. A first charge storage capacitor is connected from between the first diode and the receiver output to ground. A second charge storage capacitor is connected between the receiver input and the first diode. A second diode is connected from between the second charge storage capacitor and the first diode to ground. The dual diode receiver performs voltage boosting of a RF signal received at the receiver input, thereby enhancing receiver sensitivity.
1. A method for motion sensing, comprising:
generating first and second signals separated by a time corresponding to a selected range;
transmitting the first signal towards an object;
receiving a return reflected signal comprising a reflection of the first signal from the object;
mixing the return reflected signal from the object with the second signal to provide a detection signal when the object is at the selected range, wherein receiving a return reflected signal and mixing the return reflected signal with the second signal are performed by inputting the return reflected signal and the second signal into a voltage boosting receiver, comprising:
a receiver input;
a receiver output;
a first diode whose output is connected to the receiver output;
a first charge storage capacitor connected from between the first diode and the receiver output to ground;
a second charge storage capacitor connected between the receiver input and the first diode;
a second diode connected from between the second charge storage capacitor and the first diode to ground;
wherein the receiver performs voltage boosting of a signal received at the receiver input.
2. The method of claim 1 wherein the first and second diodes are oriented so they have opposed biases on positive voltages.
3. The method of claim 2 wherein the first diode is oriented to be forward biased and the second diode is oriented to be reverse biased on positive voltage.
4. The method of claim 1 wherein the first and second signals are RF bursts.
5. The method of claim 4 wherein the RF bursts each have a length of tens of nanoseconds.
6. The method of claim 1 wherein the first and second signals are pulses.
7. The method of claim 6 wherein the pulses each have a pulse width of about 10 ps to about 1 ns.
8. The method of claim 1 wherein the first and second signals are formed at a rate bf about 100 kHz to about 15 MHz.
9. The method of claim 1 wherein the first and second signals a generated and transmitted by a wideband or an ultra-wideband radar transmitter.
10. The method of claim 1 wherein the first signal is generated and transmitted by a transmitter comprising an oscillator, a short burst generator connected to the oscillator, and a transmit antenna connected to the short burst generator.
11. The method of claim 10 further comprising an oscillator, a short burst generator connected to the oscillator for generating the second signal, the short burst oscillator connected to the receiver input of the voltage boosting receiver, and a receive antenna connected to the receiver input of the voltage boosting receiver.