Communication unit, integrated circuits and method for clock and data synchronization

A method for clock distribution and synchronization in a radar unit having at least one master device and at least one slave device configured in a master-slave arrangement, wherein the at least one slave device and the at least one master device are connected through transmission lines, wherein the method includes, at each of the at least one master device and at least one slave device, performing steps of:

• receiving a distributed reference clock signal, wherein the distributed reference clock signal includes a system clock signal modulated with a chirp start signal;
• producing a re-created system clock signal and a reproduced chirp start signal from the distributed reference clock signal;
• receiving the re-created system clock signal at an internally-generated reference phase locked loop, and creating a master-slave clock signal based on the re-created system clock signal;
• and
• using the re-created master-slave clock signal and the reproduced chirp start signal at an analog-to-digital converter, ADC, to align respective sampling instants of a received representation of an echo signal, resulting from a transmitted frequency modulated signal, between each ADC of the at least one master device and at least one slave device.

A radar unit comprising:

• a master device configured to
• transmit a chirp signal based on a chirp start signal,
• produce a modulated embedded master-slave clock signal that includes a system clock signal modulated by the chirp start signal,
• distribute the modulated embedded master-slave clock signal, as a distributed system clock signal, to the master device and to a slave device,
• receive the distributed system clock signal,
• produce a re-created system clock signal and a reproduced chirp start signal from the distributed system clock signal,
• receive a first echo signal resulting from the transmitted chirp signal, and
• sample a representation of the first echo signal, wherein sampling instants of the representation of the first echo signal are aligned based on the re-created system clock signal and the reproduced chirp start signal;
• and
• the slave device coupled to the master device in a master-slave arrangement, wherein the slave device is configured to
• receive the distributed system clock signal,
• produce the re-created system clock signal and the reproduced chirp start signal from the distributed system clock signal,
• receive a second echo signal resulting from the transmitted chirp signal, and
• sample a representation of the second echo signal, wherein sampling instants of the representation of the second echo signal are aligned based on the re-created system clock signal and the reproduced chirp start signal.