Processing module and associated method

A processing module for a receiver device configured to provide for processing of a signal received by the receiver device from a transmitter device, the signal comprising a secure training sequence divided into a plurality of time spaced blocks, the secure training sequence comprising a non-repeating pattern of symbols, and wherein one of:

• a) at least a first block is transmitted from a first antenna and a second block is transmitted from a different second antenna of the transmitter device;
• b) at least a first block is received by a first antenna and a second block is received by a different second antenna of the receiver device;
• wherein the processing module is configured to:
• based on a plurality of repeating, predetermined synchronization symbols of the signal, provide for determination of a phase of a carrier wave of the signal received at the first antenna of the receiver device or transmitted from a first antenna of the transmitter device;
• derive a secure training sequence corresponding to the secure training sequence of the signal based on predetermined secure information known to both the transmitter and receiver device, the secure training sequence comprising a non-repeating pattern of symbols;
• perform cross correlation between the first block from the first antenna and a first part of the derived secure training sequence to obtain a first phase marker defining a phase of the signal from the first antenna relative to the determined phase of the carrier wave;
• perform cross correlation between the second block from the second antenna and a second part of the derived secure training sequence to obtain a second phase marker defining a phase of the signal from the second antenna relative to the determined phase of the carrier wave;
• based on the first phase marker and the second phase marker defining a phase difference of the signal between the first and second antennas and a known spacing of the first antenna relative to the second antenna, determine an angle of arrival of the signal relative to the receiver device.