CSR brings premium audio …

CSR brings premium audio quality to the near and far end with fifth generation CVC

Cambridge, UK - 2 June 2009 - CSR (LSE: CSR) today announced the release of fifth generation Clear Voice Capture (CVC(R)). CVC 5.0 is the only solution on the market that provides state of the art audio enhancements and noise suppression to the near and far end; as well as providing packet loss and bit error concealment for an improved user experience when using a Bluetooth headset. Available now, CVC 5.0 features in CSR's new BlueCore ROM mono headset solution BC6140 and as a software feature in BlueCore5-Multimedia. It will also be available on the forthcoming BC6150 chip.

CSR's CVC 5.0 enables OEMs to create highly versatile and differentiated devices with industry leading wireless audio performance. CVC 5.0 is a modular suite of advanced speech processing algorithms that works with both single and dual-microphone headsets, and brings a range of powerful audio enhancement technologies to the near end user, as well as providing excellent speech quality for the far end. CSR's dual-microphone option delivers more than 30dB of dynamic noise suppression in harsh acoustic conditions irrespective of the direction of noise.

CSR's fifth generation CVC features packet loss and bit error concealment technologies to improve the robustness of incoming wireless audio and mask any break-up in signal caused by surrounding RF interference. Such break-up can come from being close to a 'noisy' device such as a microwave oven or simply from cross-body interference.

At the near end the suite of audio enhancements provide a unique noise suppression algorithm to significantly reduce unwanted noise embedded in the received speech. The software also incorporates an adaptive equaliser that improves intelligibility by shaping the received speech to exploit the naturally sensitive areas of the human hearing system. The system is also able to fully compensate for the background noise the user is experiencing by adapting to external noise levels. An automatic gain control dynamically adjusts the amplitude of the received speech to ensure that the headset user can hear the incoming voice clearly.

CVC 5.0 also provides advanced far end audio enhancements including an acoustic echo canceller to reduce acoustic coupling between the loudspeaker and the microphone. Also included are single and dual-channel noise suppression algorithms that dynamically process the microphone signals to deliver clear speech at the far end of the link. The speech is further strengthened and amplified through equalisation and gain control.

"CSR is the only company that can offer a complete headset solution with both near and far end audio enhancements," said Anthony Murray, Senior Vice President of CSR's Audio and Connectivity Business Unit. "Consumers demand a very high level of wireless audio quality and have the right to expect this at both ends. With CVC 5.0, CSR delivers a complete suite of audio enhancements in a single package. We have compensated for many of the common factors that affect Bluetooth headset users; nearby devices, cross-body problems, noisy environments, etc, while maintaining the power-efficiency and wireless performance quality for which CSR is so well known."

Dual-microphone dynamic noise reduction with CVC 5.0 provides the very highest levels of delivered speech clarity to the far end, despite any presence of significant dynamic background noise from any direction. This architecture allows CVC 5.0 to separate out the voice signals of interest from the noise using proprietary signal extraction techniques. The rich suite of DSP algorithms in single and dual microphone CVC 5.0 allows users to hear and be heard much more clearly, extending the usability of Bluetooth headsets into more challenging acoustic environments.

Bluetooth headset design is further supported by the CVC Parameter Manager tool. This allows the manufacturer to tune software blocks at product design to achieve optimum performance with any type of headset plastic. With CSR's power efficient DSP-based algorithms the headset supplier can also achieve long battery life as well as the advantages of superb noise reduction features.

CVC 5.0 is available in the industry renowned BlueCore5-Multimedia flash based chip and associated software development kits.