This page contains additional information about some of our MMIC/RFIC designs.
2-18GHz MMIC up-converter
The UK Defence Evaluation and Research Agency (DERA) commissioned Plextek RFI to undertake the design and evaluation of a 2-18GHz upconverter IC for Electronic Surveillance Measures (ESM) applications. The function of the IC was to enable a signal anywhere in the 2-18GHz frequency band to be converted to 21-23GHz for subsequent downconversion to an IF suitable for digitisation; the required LO range is therefore 23-41GHz. The RF, LO and IF ports of the IC were all single ended but in order to achieve adequate port to port isolation the internal mixer was balanced at all ports. The IC therefore included novel broadband active and passive balun structures to convert the single-ended signals to differential. The IC was fabricated on the Qorvo\TriQuint Semiconductor Texas’ 0.25mm PHEMT process and has a measured conversion loss of 7dB to 14GHz, rising to 10dB by 18GHz. Input return loss is better than 12dB from 2 to 18GHz and LO rejection is over 30dB across the band.
Plextek RFI’s knowledge of high volume commercial product development and an in-depth understanding of mm-wave technology allowed the team to develop a range of low cost 40 to 43GHz mm-wave components for a high data rate wireless infrastructure system. This work included the development of full custom LNA, PA and switch MMICs. The LNA and PA were realised on a short gate length PHEMT process but this process was not suitable for implementing low loss mm-wave switches. Qorvo\Triquint Semiconductors’ commercially available GaAs Vertical PIN diode (VPIN) process was selected for this purpose and Single Pole Double Throw (SPDT) and Single Pole 4 Throw (SP4T) switch designs were produced. Parts addressing the entire 24 to 45GHz band were developed in two bands: 24 to 34GHz and 34 to 45GHz. The resulting MMICs exhibited a measured performance in close agreement with simulated and had an insertion loss of around 1dB.
CMOS transceivers for 1.8GHz and 2.4GHz applications
When National Semiconductor Corporation needed to ensure their new range of digital wireless tranceivers were launched on time, Plextek RFI was on hand to provide the experienced design skills required. The resulting products were successfully launched and to date over 500 million units have been sold. Plextek RFI’s team worked as an extension of National’s own design team with responsibility for key blocks but also attending project meetings and collaborating with the development of the complete radio transceiver.
GaAs phase shifters for phased array applications
Phase shifters find applications in electronic beam-forming, channel matching networks and measurement systems. MMIC implementations are particularly attractive for electronic beam-forming applications because they are small, repeatable and can be produced in low cost at high volumes. Plextek RFI has a long history of phase shifter MMIC design including stand-alone phase shifter MMICs, gain/phase control MMICs, core chips and complete Tx/Rx module for phased array radars.