The accurate comparison (or calibration) of conventional solid-state noise sources is often thought to be a difficult process that only specialized laboratories can perform. In this paper, the uncertainties due to the impedance differences between the sources and their on and off states are emphasized and a simple formula is developed that makes them negligible. It requires an isolator being used in front of the receiver. In the experimental section, the errors associated with common practice are evidenced and compared to what can be achieved through the correction formula.

Two compact H-band (220–325 GHz) low-noise millimeter-wave monolithic integrated circuit (MMIC) amplifiers have been developed, based on a grounded coplanar waveguide (GCPW) technology utilizing 50 and 35 nm metamorphic high electron mobility transistors (mHEMTs). For low-loss packaging of the circuits, a set of waveguide-to-microstrip transitions has been realized on 50-μm-thick GaAs substrates demonstrating an insertion loss of <0.5 dB at 243 GHz. By applying the 50 nm gate-length process, a four-stage cascode amplifier module achieved a small-signal gain of 30.6 dB at 243 GHz and more than 28 dB in the bandwidth from 218 to 280 GHz. A second amplifier module, based on the 35-nm mHEMT technology, demonstrated a considerably improved gain of 34.6 dB at 243 GHz and more than 32 dB between 210 and 280 GHz. At the operating frequency, the two broadband low-noise amplifier modules achieved a room temperature noise figure of 5.6 dB (50 nm) and 5.0 dB (35 nm), respectively.

This paper, following up on the previous work, investigates the effect of the input coupler's load termination of a balanced amplifier in a beam-steering system. The noise generated in this load termination deteriorates the amplifier noise resistance, which increases the noise temperature due to a varying active reflection coefficient at the antenna ports as a function of scan angle. In reducing this effect, the balanced configuration is made more favorable for radio astronomy applications. By lowering the value of the impedance termination on the fourth port of the quadrature coupler an improvement in noise temperature sensitivity is achieved at the cost of reduced power matching.

Wireless data communication is pushing towards 60 GHz and will most likely be served by SiGe and Complementary Metal Oxide Semiconductor (CMOS) technologies in the consumer market. Nevertheless, some applications are imposing superior performance requirements on the analog frontend, and employing III-V compound semiconductors can provide significant advantages with respect to transmitter power and noise figure. In this paper, we present essential building blocks and a novel single-chip low complexity transceiver Monolithic Microwave Integrated Circuit (MMIC) with integrated antenna switches for 60 GHz communication, fabricated in a 100 nm metamorphic high electron mobility transistor (mHEMT) technology. This technology features a measured noise figure of <2.5 dB in low-noise amplifiers at 60 GHz and the realized medium power amplifiers achieve more than 20 dBm saturated output power. Integrated antenna switches with an insertion loss of less than 1.5 dB enable the integration of the transmit and the receive stages on a single chip. A single-chip transceiver with external subharmonic Local Oscillator (LO) supply for its I/Q down- and up-converter achieves a linear conversion gain in both, the Transmit (Tx) and the Receive (Rx) paths, of more than 10 dB.