Multichannel, single PLL GNSS RF streamer with high interchannel coherence. A single, optimized local oscillator, featuring ultra-low phase noise further to a specialized PLL design and the use of a high performance OCXO, is exploited to maintain the mutual coherence properties of signals coming from up to four different antennas. Particularly suited for GNSS antenna array research and applications (e.g. direction of arrival detection).