Radar system comprising coupling device

1. A radar system comprising: a plurality of integrated circuits ICs, each IC comprising:

a respective local oscillator LO output for selectively outputting a respective LO signal, and a respective LO input; and a coupling device, the coupling device comprising:

a plurality of inputs, each input being coupled to the LO output of a respective IC, and a plurality of outputs, each output being coupled to the LO input of a respective IC;

wherein the coupling device is configured such that a LO signal arriving at any one of said plurality of inputs is distributed to each of said plurality of outputs.

2. The radar system of claim 1 , wherein said coupling device comprises at least one directional coupler.

3. The radar system of claim 2 , wherein said at least one directional coupler comprises at least one of a branch line coupler or a rat race coupler.

4. The radar system of claim 1 , wherein said coupling device comprises at least one waveguide coupler.

5. The radar system of claim 1 , wherein said coupling device comprises a plurality of directional couplers.

6. The radar system of claim 1 , configured such that only one of said plurality of ICs outputs a respective LO signal when the radar system is in use acquiring radar data.

7. The radar system of claim 1 , wherein:

each one of said plurality of ICs is selectively configurable (i) as a master IC configured to output a common LO signal at its respective LO output and (ii) as a slave IC configured to receive the common LO signal from the master IC via said coupling device at its respective LO input.

8. The radar system of claim 1 , wherein each IC of said plurality of ICs is a transceiver IC or is comprised in a transceiver, receiver or transmitter chipset.

9. The radar system of claim 1 , further comprising phase compensation circuitry for compensating a phase difference between the outputs of the coupling device.

10. The radar system of claim 9 , wherein said phase compensation circuitry comprises at least one delay line.

11. The radar system of claim 9 , wherein said phase compensation circuitry comprises at least one phase rotator.

12. The radar system of claim 1 , further comprising:

first circuitry for introducing a first phase shift into a signal received at a first respective input of the plurality of inputs of the coupling device from a first IC of the plurality of ICs, and

second circuitry for introducing a second phase shift into a signal received at a second respective input of the plurality of inputs of the coupling device from a second IC of the plurality of ICs,

wherein said second phase shift is greater than said first phase shift.

13. The radar system of claim 12 , wherein said first and second circuitry comprises respective first and second delay lines.

14. An autonomous vehicle comprising a radar system, the radar system comprising:

a plurality of integrated circuits ICs, each IC comprising:

a respective local oscillator LO output for selectively outputting a respective LO signal, and

a respective LO input; and a coupling device, the coupling device comprising:

a plurality of inputs, each input being coupled to the LO output of a respective IC, and a plurality of outputs, each output being coupled to the LO input of a respective IC;

wherein the coupling device is configured such that a LO signal arriving at any one of said plurality of inputs is distributed to each of said plurality of outputs.

15. A method of operating a radar system, the radar system comprising: a plurality of radar integrated circuits ICs, each IC comprising a respective local oscillator LO output for selectively outputting a respective LO signal, and a respective LO input; and a coupling device, the coupling device comprising: a plurality of inputs, each input being coupled to the LO output of a respective IC, and a plurality of outputs, each output being coupled to the LO input of a respective IC;

wherein the coupling device is configured such that a LO signal arriving at any one of said plurality of inputs is distributed to each of said plurality of outputs; the method comprising:

operating the radar system in a first configuration, in which a first IC of said plurality of ICs is configured to output a common LO signal, and the other ICs of said plurality of ICs are configured to receive said common LO signal from said first IC;

and reconfiguring the radar system to a second configuration, in which a second IC of said plurality of ICs is reconfigured to output a common LO signal.

16. The method of claim 15 , further comprising outputting a respective LO signal by only one of said plurality of radar ICs when the radar system is in use acquiring radar data.

17. The method of claim 15 , wherein each IC of said plurality of radar ICs is a transceiver IC or is comprised in a transceiver, receiver or transmitter chipset.

18. The method of claim 15 , further comprising compensating by way of phase compensation circuitry a phase difference between the outputs of the coupling device.

19. The method of claim 15 , further comprising:

introducing a first phase shift into a signal received at a first respective input of the plurality of inputs of the coupling device from a first radar IC of the plurality of radar ICs; and

introducing a second phase shift greater than said first phase shift into a signal received at a second respective input of the plurality of inputs of the coupling device from a second radar IC of the plurality of radar ICs.

20. The method of claim 15 , wherein said coupling device comprises at least one directional coupler, the directional coupler comprising at least one of a branch line coupler or a rat race coupler.