Single-Chip Modem Supports Variable-Rate Vocoding For CDMA

The MSM2310 Mobile Station Modem IC is claimed as the first single-chip, tri-mode vocoder device to support enhanced variable-rate vocoding (EVRC). The device, which supports all three CDMA vocoders, will enable designers to create smaller EVRC CDMA handsets by reducing the necessary board area and weight.Based on the company's MSM2300 architecture, the chip has applications in subscriber units for worldwide multi-mode cellular, PCS handsets and data communication devices. It's pin-compatible with MSM2300 chips, offering easy migration to users of the earlier device with a minor software upgrade. The result is rapid design of EVRC-capable handsets and elimination of costly DSP implementations. The EVRC implementation runs at less than 20 MIPS, which is said to be significantly less than other implementations. Other signal processing functions performed by the MSM2310 include noise cancellation, acoustic echo cancellation, and DTMF generation.