The AD6635 is a multi-mode eight channel digital Receive Signal Processor (RSP) capable of processing up to four WCDMA channels. Each channel consists of four cascaded signal-processing elements: a frequency translator, two CIC decimating filters, and a programmable coefficient-decimating filter. Each input port has input level threshold detection circuitry and an AGC controller for accommodating large dynamic ranges or situations where gain ranging converters are used. Quad 16-bit parallel output ports accomodate high data rate WBCDMA applications. On-chip interpolating half band filters can also be used to further increase the output rate. In addition, each parallel output port has a digital AGC for output data scaling. Link port outputs are provided to enable glueless interfaces to Analog Devices’ TigerSHARC™ DSP core.
The AD6635 is part of Analog Devices’ SoftCell™ Multi-carrier transceiver chipset designed for compatibility with Analog Devices family of high sample rate IF sampling ADCs (AD6640/AD6644 12 & 14 bit). The SoftCell™ receiver comprises a digital receiver capable of digitizing an entire spectrum of carriers and digitally selecting the carrier of interest for tuning and channel selection. This architecture eliminates redundant radios in wireless base station applications.