Highly Linear Phase Shifter with L-Topology PIN Diode-Based Switch

In modern telecommunication systems, such as full-duplex transceivers where transmission and reception operate simultaneously at the same frequency, the linearity of components in the shared path is critical to avoid interference. In these transceivers, phase shifter distortion represents a primary source of nonlinearity, thereby limiting receiver sensitivity. This paper introduces a highly linear one-bit switched line phase shifter utilizing an adapted L-topology PIN diode-based RF switch. This design is specifically engineered to minimize reverse distortion, a critical limiting factor in the sensitivity of receivers. The phase shifter is engineered to provide a 45-degree phase shift, serving as a proof of concept. The design is simulated and measured. The results show an insertion loss (IL) of 1.2 dB, and a third-order input intercept point (IIP3) of 95 dBm, demonstrating the proposed design's exceptional linearity.