Abstract
One of the efficient options to reduce the transceiver die area is to combine some building blocks operating at a similar frequency range from the transmitter and receiver chains to introduce a bi-directional signal flow capability. The chapter presents a high-linearity low-noise amplifier design, which is further extended to provide switchable directional control. Such bi-directional amplifiers are mainly used in the compact radio frequency (RF) transceivers and a prominent application is the phase array systems used to achieve beam forming and beam scanning in the radar and defense communication systems. The bulkiest module or component in the RF transceiver system form-factor is the antenna. This will be a bigger concern when considering antenna arrays for beam-forming applications and phase arrays designed for wireless communication. One benefit with the antenna design is they are bi-directional transducer components and the same design can work as transmitting as well as receiving antenna.