X-Band and Ka Band Low Noise Block Downconverter

Custom MMIC Design Services has significant experience in the design, characterization and destruction testing of MMW LNAs. We have successfully designed X-band LNAs on GaAs with sub 1dB noise figures. These designs have been shown to survive up to 1W of RF power with no input protection. CMDS has also designed diode based limiter circuits to extend that protection to 6W. Our innovative design techniques and modeling capability have ensured that first pass designs with world class performance are possible. These techniques will be used to create GaN devices that need no input limiter and therefore exhibit composite noise figures that are significantly improved from GaAs devices. When coupled with a much higher OIP3 the overall dynamic range of the system will be extended. The improved performance will derive from the wide band gap of the device creating higher pinchoff voltages which directly relate to the voltage swing that is present upon the device when an incident high power signal is encountered. When coupled with circuit techniques that incorporate elements to limit these voltages input levels of greater than 5W will be achievable. BENEFIT: These LNAs will provide lower overall noise figures (when compared to protected GaAs devices) and higher OIP3 values such that the system dynamic range will be greatly improved. As GaN power amplifier volumes rise the processes will transition to 4"wafers and costs will begin to fall. At that point the RF improvements will be cost effective and can be rolled into systems. At the same time CMDS will develop other RF functions for the block downconverter systems including mixers, switches, and attenuators. These too can provide significant benefits to the block downconverter system.