Work

Photonic approach for multi-source blind signal separation and angle of arrival measurement

Year: 2026

Type: article

Abstract: This paper proposes and experimentally validates a microwave photonic system for joint blind source separation (BSS) and angle of arrival (AOA) estimation of multi-source signals. By integrating digital signal processing algorithm, the system enables effective separation of multiple signals and accurate angle identification. In the experiment, two RF signals at 18 GHz and 21 GHz are directly generated by an arbitrary waveform generator. The two RF signals are applied to a dual-drive Mach–Zehnder modulator (DDMZM) together with a local oscillator signal. The modulator is biased at its minimum transmission point, and the desired difference‐frequency component is selected. The photodetector converts the optical signal output from DDMZM into a down-converted intermediate-frequency (IF) signal. The waveforms of the mixed IF signal are collected by an oscilloscope. In the data processing stage, the JADE algorithm is used to perform BSS on the IF mixed signal, then two IF signals are separated and recovered. Subsequently, the separated signals are input into the MUSIC algorithm. Through spatial spectrum construction and peak searching, precise estimation of the incident angle of each signal is achieved. Experimental results show that, under the emulated AOA conditions, the estimation error over the range of 0° to 90° is within ±1.4°.

Source: Journal of Optics

DOI: 10.1088/2040-8986/ae9e44