RF pair suit millimetre-wave radio systems

Edited by the Electronicstalk editorial team Jul 20, 2005

New from Mimix Broadband are a pair of gallium arsenide (GaAs) monolithic microwave integrated circuit (MMIC) subharmonically pumped receiver and transmitter devices.

New gallium arsenide (GaAs) monolithic microwave integrated circuit (MMIC) subharmonically pumped receiver and transmitter devices integrate an image reject subharmonic antiparallel diode mixer, an LO buffer amplifier and a low noise amplifier for the receiver, and an output amplifier for the transmitter.

The image reject mixer eliminates the need for an image bandpass filter after the amplifier to remove thermal noise at the image frequency.

Using 0.15um gate length GaAs pseudomorphic high electron mobility transistor (pHEMT) device model technology, these devices cover the 18 to 25GHz frequency bands.

The receiver has a noise figure of 2.5dB and 15dB image rejection across the band.

The transmitter has a +20dBm output third order intercept point (OIP3) and 15dB image rejection across the band.

This receiver and transmitter pair, identified as XR1006 and XU1002, respectively, are well suited for wireless communications applications such as millimetre-wave point-to-point radio, local multipoint distribution services (LMDS), satcom and Vsat applications.

"These highly integrated parts significantly lower the millimetre-wave chip count in microwave radios", stated Dr Jim Harvey, CTO of Mimix Broadband.

"Each part replaces three or four separate functions, improving manufacturability and lowering assembly and parts cost, and they are important additions to the Mimix 3-chip solution".

Mimix performs 100% on-wafer RF and DC on these products, as well as 100% visual inspection to MIL-STD-883 method 2010.

The chips also have surface passivation to protect and provide rugged parts with backside via holes and gold metallisation to allow either a conductive epoxy or eutectic solder die attach process.