This seminar 2 presents my continued research work on phased array receivers for 5G millimeter wave communications. First, the design and analysis of a 28GHz CMOS Low Noise Amplifier is discussed. A current reuse technique is used to minimize power consumption by stacking two common source amplifiers. Next, some modifications on the previously presented transmission-line based bidirectional reflection-type phase shifter are discussed, with implementation at 3.5 GHz. Finally, a fully bidirectional phased array transceiver front end operating in the 24.25-27.5GHz band is presented. There is no explicit T/R switch or matching network required. In measurements, the achieved saturated output power and power-add efficiency in TX-mode are 12 dBm and 13.1%,respectively. The RX-mode noise figure is 9.6 dB at 26 GHz. The fabricated chip achieves a measured phase resolution of 2.8 degrees at 26GHz, with an RMS error of 0.6 degrees and a total phase shift of 180 degrees. The active area of the entire phased array bidirectional front-end transceiver is 0.38 sq mm, which makes it ideal for large
phased array systems.