Orthogonal phase modulation for detection and communication in radar

A method of orthogonal modulation of radar waves of a phase-modulated continuous wave radar system by a sequence of numerical communication symbols, the method comprising steps of:

• selecting an equidistant bi-phased or multi-phased phase-modulation sequence, wherein members of the sequence are given by complex roots of unity,
• phase-modulating the continuous radar wave of the radar system, and
• transmitting the orthogonal phase-modulated continuous radar wave towards a scene,
• and the method being characterized by the following steps of:
• generating a detection sequence (s) by applying an outer coding (H) to the bi-phased or multi-phased phase-modulation sequence,
• selecting a communication range (C) in the complex number plane, based on the selected equidistant bi-phased or multi-phased phase-modulation,
• generating a communication sequence (c) comprising a plurality of sequence members, wherein the members are natural numbers,
• mapping the communication sequence (c) into the communication range (C) by applying an injective mapping function (Γ) to the members of the communication sequence (c),
• calculating a numerical product of members of the detection sequence (s) with members of an image of the mapped communication sequence (c),
• wherein the step of phase-modulating the continuous radar wave of the radar system is carried out according to the calculated numerical products.