Apparatus for generating an integrator timing reference from a local oscillator signal
View Patent ↗A receiver circuit including an oscillator, a mixer coupled to the oscillator, a switch coupled to an output of the mixer, and an envelope detector coupled to the oscillator, such that the envelope detector generates a timing signal for actuating the switch based on the envelope of a signal produced by the oscillator. In one exemplary embodiment, the receiver circuit may be used as part of a radar based sensor system.
1. A circuit comprising:
an oscillator;
a mixer coupled to the oscillator;
a switch coupled to an output of the mixer; and,
an envelope detector coupled to the oscillator,
wherein an envelope detector generates a timing signal for actuating the switch based on the envelope of a signal produced by the oscillator.
2. The circuit of claim 1 , further comprising:
an amplifier coupled between the mixer and the switch.
3. The circuit of claim 1 , wherein the timing signal oscillates between a first state and a second state.
4. The circuit of claim 3 , wherein the first state corresponds to an oscillating signal produced by the oscillator, and the second state corresponds to a non-oscillating signal produced by the oscillator.
5. The circuit of claim 3 , wherein said first state corresponds to a first voltage value and said second state corresponds to a second voltage value.
6. A receiver comprising:
an antenna capable of receiving at least one reflected signal from an object;
an oscillator;
a mixer coupled to the oscillator, said mixer operating on said at least one reflected signal and a signal produced by said oscillator;
a switch coupled to an output of the mixer; and,
an envelope detector coupled to the oscillator,
wherein the envelope detector generates a timing signal for actuating the switch based on the envelope of a signal produced by the oscillator.
7. The receiver of claim 6 , wherein the timing signal oscillates between a first state and a second state.
8. A sensor system comprising:
a transmitter for transmitting at least one pulse towards an object; and
a receiver for receiving at least one pulse reflected off of the object, said receiver comprising:
an oscillator;
a mixer coupled to the oscillator;
a first switch coupled to an output of the mixer; and,
an envelope detector coupled to the oscillator,
wherein the envelope detector generates a timing signal for actuating the switch based on the envelope of a signal produced by the oscillator.
9. The sensor system of claim 8 , further comprising a second switch for selecting one of either the transmitter or receiver.
10. The sensor system of claim 8 , further comprising a sample and hold circuit coupled to the output of the first switch.
11. The sensor system of claim 8 , further comprising at least one antenna coupled to the transmitter for transmitting a signal towards an object.
12. The sensor system of claim 8 , wherein the timing signal oscillates between a first state and a second state.