Performance Evaluation of a 32-QAM 1-Meter Wireless Link Operating at 220-260 GHz with a Data-Rate of 90 Gbps

This paper evaluates a 32-QAM 1-meter wireless link at a tunable carrier of 220-260 GHz. The link was established using a set of fully-packaged fundamentally-operated direct conversion IQ Tx and Rx modules implemented in a SiGe HBT technology with f(T)/f(max)=350/550 GHz.Exemplary, at 230 GHz, the Tx module shows a 3-dB RF bandwidth of 28 GHz, a P-sat of 8.3 dBm and an output-referred P-1dB of 4.5 dBm, while the Rx module shows a 3-dB RF BW of 24 GHz, a CG of 24 dB and an estimated SSB NF of 12 dB. The IQ amplitude imbalance of both modules stays below 0.5 dB. The directivity of the modules grows monotonically between 25 and 27 dBi in the 210-270 GHz band. A maximum data-rate of 90 Gbps was achieved using carrier frequencies in the range of 230-245 GHz. The paper provides a system level analysis of the link limitations in terms of the RF front-end imperfections.