CSR (LSE:CSR) launched its sixth generation of BlueCore silicon for Bluetooth. BlueCore6 includes both industry-leading radio performance and power consumption, as well as full support for the latest version (v2.1+EDR) of the Bluetooth specification. Included in BlueCore6 is CSR’s AuriStream(TM) technology, a radical improvement to the way Bluetooth handles voice traffic; AuriStream provides toll quality voice calls and is capable of a 40% reduction in power consumption in BlueCore6-ROM compared with standard Bluetooth voice transmission methods. Volume production will commence in Q1 2008.
CSR has enhanced the RF performance to give BlueCore6 Class 1 Bluetooth range without the need for an external power amplifier. A total 11dB link margin improvement over BlueCore4 (+4dBm to Tx, -7dBm to Rx) makes BlueCore6 the industry’s most efficient Bluetooth radio and helps improve operation across the body, for example when a Bluetooth headset connects to a mobile phone worn on the user’s belt. BlueCore6-ROM is packaged in CSR’s tried and tested wafer level CSP format and is smaller than competing Bluetooth silicon.
Voice remains the key application for Bluetooth, and users continually demand higher voice quality – but also longer battery life. CSR’s BlueCore6 has inherited all of the features that made BlueCore4 the world’s leading Bluetooth silicon, plus substantial improvements in both voice quality and power requirements.
Fiona Thomson, Senior Analyst at IMS Research commented, “Our own research has shown us that consumers are asking for the power and performance improvements that CSR is delivering with its new BlueCore6 product.” Thomson continued, “As CSR continues to push the market boundaries with its Bluetooth products, these improved features will benefit the end consumer and keep CSR’s products at the forefront of handset and headset manufacturers’ minds.”
Bluetooth traditionally relies on a Continuous Variable Slope Delta (CVSD) modulation coding scheme to carry voice over a Synchronous Connection Oriented (SCO) link. CVSD is a fairly simplistic binary coding scheme, but was selected because it is highly robust and resistant to bit errors. However, SCO does not allow for retransmission of failed packets. Since v1.2 of the Bluetooth specification, eSCO has supported retransmissions. With AuriStream CSR has introduced Adaptive Differential Pulse Code Modulation (ADPCM) as an enhanced voice coding method, since it performs the same function at half the rate of CVSD (ADPCM scans at 32Kbps, CVSD 64Kbps) saving up to half the Bluetooth power on the handset; ADPCM is more accurate, and provides a much higher voice quality. CSR’s AuriStream boosts quality from a Mean Opinion Score of 2.41 with CVSD to a toll quality score of 4.14, bringing fixed line quality to a Bluetooth connection.
CSR has introduced a range of technologies into BlueCore6 all of which bring important savings on either the Bluetooth or the host device’s power consumption for mobile phone architectures. CSR has reduced the power in standby and restructured how Bluetooth devices scan for other devices. On average standby current accounts for over half the total power consumption of a Bluetooth system.
CSR has added two improved scan modes in BlueCore6: conditional scan and casual scan. By combining these techniques CSR’s BlueCore6-ROM can save up to 86% of Bluetooth’s power consumption in scan mode.
When using conditional scan, BlueCore will wake up the minimum parts of the radio to perform a quick scan for any activity in the 2.4GHz band, if the radio discovers activity, it will initiate a normal Bluetooth page scan/inquiry. If not, the radio will remain asleep.
CSR’s casual scan mode synchronises the periodic wake up of BlueCore6-ROM with that of the attached baseband device, consequently BlueCore6-ROM does not wake up the host VCTXO unnecessarily. The Bluetooth silicon often shares a VCTXO with a mobile phone’s host system to minimise the use of additional components and save power on the cellphone system.
CSR CEO John Scarisbrick commented, “BlueCore6 is CSR’s most important Bluetooth silicon to date and offers more unique new technologies than any previous generation we have launched. The fact that the technologies inside BlueCore6 are way ahead of anything else on the market today clearly demonstrates that CSR continues to be the leader in wireless innovations.” Scarisbrick continued, “We have already had substantial interest in BlueCore6 from key handset and headset tier one manufacturers.”
CSR is the leading global provider of personal wireless technology and its product portfolio covers Bluetooth, GPS, FM receivers and WiFi (IEEE802.11). CSR offers developed hardware/software solutions based around its silicon platforms that incorporate fully integrated radio, baseband and microcontroller elements. CSR’s customers include industry leaders such as Apple, Dell, LG, Motorola, NEC, Nokia, Panasonic, RIM, Samsung, Sharp, Sony, TomTom and Toshiba. CSR has its headquarters and offices in Cambridge, UK, and offices in Japan, Korea, Taiwan, China, India, France, Denmark, Sweden and both Dallas and Detroit in the USA.