Multi-Antenna RF Tag Measurement System Using Back-Scattered Spread Spectrum

This paper presents the design, construction, and operation of a unique measurement system capable of recording simultaneous antenna measurements in a backscatter radio configuration with genuine mutual coupling effects. The system allows rapid-fire design and testing of the increasingly important multi-antenna RF tag designs as well as low-level physical-layer experiments involving anticollision (numerous RF tags communicating with one another in a common field of view), RF tag shadowing, and multi-antenna fading experiments.