Power amplifiers that provide both high linearity and high efficiency are essential for the transmission of high data rate bandwidth efficient digital signals used in modern MILSATCOM communications. Achieving this objective at millimeter-wave (MMW) frequencies is particularly challenging; high power amplifiers (HPAâs) are heavy, costly, and inefficient. Linearizer Technology Inc. (LTI/LTI-GOV) in conjunction with L3 Technologies (L3) is proposing to develop a dual band linearized high power amplifier (HPA) that covers both the Ka Band (29 to 31 GHz) and Q Band (43.5 to 45.5 GHz) SATCOM uplink bands with the goal of greater than 100 watts output power, a linear output power of 50 watts, and power added efficiency (PAE) of at least 36% at saturation and 25% at 3 dB output power backoff (OPBO). The HPAâs linear performance is based on QPSK and 8PSK signals having better than 30 dB adjacent channel power ratio (ACPR) with an OPBO of 3 dB or less across the bands, and operating up to 80º C. To achieve the required power and efficiency, the HPA will be based on an existing microwave power module (MPM) that integrates a TWT and power supply, developed by L3, which provides over 70 watts in the