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VoIP reference design

UniVox is a VoIP (Voice-over- Internet-Protocol)-phone reference design based on the CSR (Cambridge Silicon Radio) UniFi single-chip WiFi device. CSR has designed UniVox to enable manufacturers to produce wireless phones for residential use at low cost and power with up to 20 hours talk time and 400 hours standby time from typical (1500 mAh) handset batteries, using latest generation access points. CSR is providing UniVox customers with schematics, layout and bill of materials (BOM) as well as royalty-free design software. The BOM is under $20 with the electronic bill of materials (eBOM) totalling less than $15. UniFi-1 is CSR's 802.11b/g single-chip WiFi silicon that occupies a chipscale package with a footprint of 6
6 mm. CSR has also designed its own MAP (Multimedia Applications Processor) into UniVox, combining a low-power RISCbased applications processor with DSP function, audio CODECs and echo cancellation; as well as intelligent power management. UniVox supports 802.11e and WMMSA to provide optimised and prioritised quality of service (QoS), eliminating potential latency or jitter. UniVox also supports 802.11i to add enhanced levels of security, and SIP (Session Initiation Protocol) version 2, the widely adopted open standard for initiating voice or video calls across Internet connections. Designers can also configure it to support the alternative IAX2 protocol. The DSP co-processor inside CSR's applications processor includes the company's own CVC (Clear Voice Capture) echo-cancellation software.
—by Graham Prophet

CSR,www.CSR.com