This paper presents a broadband transmitter and receiver at D-band (from 123 to 146GHz) using 22nm FDSOI technology. The direct conversion receiver is implemented with a wideband fully differential LNA at the front end, using a cross coupled pair with capacitive neutralization, followed by a linear double balanced passive mixer and broadband pseudo-differential transimpedance amplifier. The direct conversion transmitter starts with an active double balanced Gilbert cell, followed by a driver amplifier. A 9:1 frequency multiplier circuit realized by two successive tripler stages provides the on-chip 135GHz Local Oscillator (LO) signal for both the Tx and Rx chains. The receiver conversion gain is 27dB with a 20GHz 3-dB bandwidth, and the P1-dB is −30dBm. The transmitter saturated output power is 2.8 dBm. Tx and Rx chains consume 196mW and 198mW respectively from a supply voltage of 0.8V.