Ultra-wideband transceiver
An ultra-wideband transceiver that includes a selection mechanism for selecting an internal or an external pulse repetition frequency generator, the output of which is used in the generation of very short duration UWB RF pulses. A detection mechanism is electrically isolated from the oscillator but shares access to a single port that is used for both transmission and reception (e.g. a physical layer transmit/receiver port) of RF signals. The detection mechanism detects changes in the received signal by comparing the received signal to a reference, amplifying these changes, removing high frequency noise and sending the resulting signal for subsequent signal processing, for example a digital signal processing system.
1. An ultra-wideband (UWB) transceiver for detecting motion of an object comprising:
a. a generator mechanism for generating a UWB radio frequency (RF) signal of short duration pulses and connected to output the generated UWB RF signal to a node;
b. a port mechanism coupled to the node, operable in a half-duplex manner between a transmit mode for transmitting the generated UWB RF signal from the node and a receive mode for receiving an UWB RF signal and providing the received UWB RF signal to the node; and
c. a detector mechanism hard-wired to the node for detecting changes of the received UWB RF signal relative to a thermal compensation reference signal, the detector mechanism configured to be insensitive to the transmitted UWB RF signal;
wherein the received UWB RF signal relative to the thermal compensation reference signal varies with motion of the object.
2. The ultra-wideband (UWB) transceiver of claim 1 wherein the generator mechanism further comprises a pulse repetition frequency (PRF) generator module and an impulse generator module which generate a transmitted pulse signal for enabling the port mechanism to switch between the transmit and receive modes.
3. The ultra-wideband (UWB) transceiver of claim 2 further comprising a diode detector module for averaging energy in the received signal over a defined period of time.
4. The ultra-wideband (UWB) transceiver of claim 3 further comprising a thermal compensation module for generating the thermal compensation reference signal based upon variations in direct current (DC) supply voltage from ambient temperature fluctuations.
5. The ultra-wideband (UWB) transceiver of claim 4 further comprising a differential amplifier module for comparing the received UWB RF signal to the thermal compensation reference signal and for amplifying a difference between the received UWB RF signal and the thermal compensation reference signal to generate a differential signal having a high frequency component.
6. The ultra-wideband (UWB) transceiver of claim 5 further comprising a baseband filter module for receiving the differential signal from the differential amplifier and removing high frequency noise components for generating an output signal.
7. The ultra-wideband (UWB) transceiver of claim 1 wherein the short duration pulses are less than a nano-second in width.
8. The ultra-wideband (UWB) transceiver of claim 7 wherein the short duration pulses created by the PRF generator are of a frequency between 1 and 30 MHz.
9. The ultra-wideband (UWB) transceiver of claim 1 further comprising a transmit/receive medium connected to the port mechanism, the medium being selected from the group consisting of an antenna, coaxial cable and twisted pair.
10. The ultra-wideband (UWB) transceiver of claim 2 wherein the transmitted pulse signal comprises a pulse stream alternating between a lower signal potential and a higher signal potential, and the port mechanism operates in the transmit mode during assertion of the lower signal potential and in the receive mode during assertion of the higher signal potential.
11. The ultra-wideband (UWB) transceiver of claim 10 wherein an input to the detector mechanism is continuously coupled to an output of the impulse generator module to receive the transmitted pulse signal, and the detector mechanism is impeded from conducting a signal when a potential difference between the input to the detector mechanism and an output of the detector mechanism is below a threshold potential.
12. The ultra-wideband (UWB) transceiver of claim 11
wherein the potential difference between the output of the detector mechanism and the input to the detector mechanism is reduced to a value below the threshold potential when the input to the detector mechanism is at the lower signal potential.
13. The ultra-wideband (UWB) transceiver of claim 12 wherein the detector mechanism comprises a first diode for detecting the received UWB RE signal, the first diode coupled to the output of the impulse generator module and reverse biased when an anode of the first diode is at the lower signal potential.
14. The ultra-wideband (UWB) transceiver of claim 13 wherein the threshold potential is above a ground potential and the lower signal potential is at the ground potential.
15. The ultra-wideband (UWB) transceiver of claim 13 wherein the detector mechanism comprises:
a. a second diode connected in parallel with the first diode for detecting the thermal compensation reference signal, the second diode continuously coupled to the port mechanism and the output of the impulse generator module; and
b. circuitry coupled between the impulse generator module and the second diode for filtering the transmitted pulse signal from a signal received at an anode of the second diode.