Tunable 500 GHz transmitter array in SiGe technology for gas spectroscopy

Abstract

A 500 GHz system for gas spectroscopy is presented, which includes an integrated SiGe 4x1 transmitter (TX)-array, a Golay cell, and a 1.9 m long gas absorption cell. The local oscillator (LO) of the TX-array is controlled by an external phase-locked loop (PLL), whose reference frequency is swept. The four TX-branches involve frequency quadruplers (x4). The TX-branches are fed by a 120 GHz power division network, which is connected to the LO. The estimated radiated output power of the TX array is 7 dBm at 500 GHz. The absorption spectrum of methanol is shown for 494 – 500 GHz.