Multi-Band Digital-RF Receiver

A software radio receiver that can be programmed to operate in multiple wide frequency bands is required for many communication and intelligence applications. We have designed a variety of multi-band receivers, comprising a set of band-specific analog-to-digital converters (ADCs) for direct digitization of RF bands and a digital switch matrix for band selection, in two flavors: as a single superconductor integrated circuit chip and also as a multi-chip module. In addition to the ADCs and the switch, these include a 1:16 deserializer and output drivers to facilitate transport of the digitized RF data to room temperature electronics for further processing and analysis. In the single IC flavor, up to four bandpass delta-sigma ADCs minimizing quantization noise in their respective bands were integrated on the same chip and operated at clock rates up to 20 GHz. In the multi-chip module (MCM) implementation, a 1-cm × 1-cm universal active carrier was designed to accommodate any two 2.5-mm × 2.5-mm flipped chips, each containing a single ADC front-end. This standardized approach facilitates customization of two-band ADCs by selecting from a growing library of ADC front-ends, which currently cover bands ranging from HF (0-30 MHz) to Ka-band (20-21 GHz). These Multi-band MCMs and single chip ADC's were fabricated, assembled and tested.