The AD6634 is a new member of ADI's VersaCOMMTM family of RSPs (receive signal processors) and TSPs (transmit signal processors), which serve as the interface between the DSP and high-speed converter in a multi-carrier transceiver. In cellular base stations, it creates baseband data for a DSP from high-bandwidth data provided by an A/D converter, and is compatible with SoftCell high-performance IF sampling ADC converters such as the AD664x, AD9042, AD943x, and the AD922x. The AD6634 is also compatible with the AD6600 diversity ADC, the combination of which provides a cost and size reduction path. The SoftCell receiver solution comprises a digital receiver capable of digitizing an entire spectrum of carriers and digitally selecting the carrier of interest for tuning and channel selection. It eliminates redundant radios in wireless base stations.

The AD6634 is a highly integrated, multi-mode, four-channel digital receive signal processor capable of processing up to two W-CDMA channels or four GSM/EDGE or IS-136 channels. Each of the AD6634’s channels consists of four cascaded signal-processing elements: a frequency translator, two fixed-coefficient decimating filters, and a programmable-coefficient decimating filter. Two wideband crossbar-switched parallel input ports offer enhanced input signal reconfigurability for multi-carrier, diversity, and phased-sector antenna arrays. Dual 16-bit parallel output ports provide a means of recombining serial outputs for high-data-rate W-CDMA applications. Link ports are provided to enable glue-less interfaces to ADI’s TigerSHARC® DSP core. The AD6634 has on-chip interpolating half-band filters to further increase the output data rate from 2 times to 4 times the chip rate. In addition, embedded digital AGC (automatic gain control) circuitry permits data scaling and power data to be fed directly to a “rake” receiver in CDMA based applications.

AD6634 Applications
·Multi-carrier, multi-mode digital receivers: GSM, IS-136, EDGE, PHS, IS-95, UMTS, cdma2000
·Micro and pico cell systems, software radios
·Wireless local loop
·Smart antenna systems
·In-building wireless telephony

Pricing and Availability
The AD6634 is available in a 196-ball BGA package and operates over the industrial temperature range of -40 to +70 degrees C. The price is $42.50 per unit in 1,000-piece quantities. Samples and evaluation boards are available now.