A 25 to 45 GHz SiGe receiver MMIC

The frequency range 25-45 GHz contains point-to-point bands at 28, 32, 38 and 42 GHz, potential implementation of 5G at 28 and 39 GHz and various military applications. Traditionally, short gate length GaAs pHEMT technology has been used to develop products for these frequencies. Alternatively, SiGe HBT technology may offer lower cost solutions for systems that can tolerate lower performance. This paper presents the design and measurements of a broadband SiGe receiver with a noise figure of 6 ± 1 dB over the entire 25 to 45 GHz bandwidth. The measured gain exceeds 20 dB from 26 to 43 GHz and, with gain control, is sufficiently linear to support 1024 QAM in the 35 to 45 GHz range. To the authors' knowledge, this the broadest bandwidth achieved to date with a SiGe receiver at these Ka or low millimetre-wave frequencies.