CSR ULP Bluetooth eyes medical apps

Wireless chip specialist CSR plc has for the first time demonstrated the Ultra Low Power (ULP) Bluetooth in silicon, targeted at a medical application.

CSR showed off the strength of the technology, which started off in 2006 as a Nokia project dubbed Wibree but was the following year incorporated into the Bluetooth SIG (Special Interest Group) as its low power derivative, at this week's Continua Health Alliance medical conference in Luxembourg.

In a presentation at the conference, Robin Heydon, CSR's standards architect, also talked for the first time about the Bluetooth Health Device Profile (HDP). CSR has designed HDP with the Bluetooth SIG to meet the specific needs of the medical electronics market.

CSR said the demonstration showed that its ULP Bluetooth silicon consumes 10 times less power than standard Bluetooth when connectable.

The set-up showed two ICs transferring ULP Bluetooth data packets 50 times faster than standard Bluetooth, meaning that the devices were consuming as little as 1/50th of the power. In addition, in establishing the connection, the ULP devices used 1/10th the power required by standard Bluetooth.

The demonstration ICs employed both standard Bluetooth (v.2.1) and ULP Bluetooth radios. CSR calls these devices "dual-mode" because they support both flavors of Bluetooth radio.

The group showed that when ULP Bluetooth is used, for example in a in a wireless heart rate monitor, the monitor simply "advertises" itself to the control/reader using just three frequencies, which could be a mobile phone or watch, that then connects sends its very short burst of data and then switches off again.

To connect devices in standard Bluetooth, the master device has to synchronize to a slave device by paging a specific device using up to 32 frequencies, it then issues frequency hopping spectrum packets, then it polls the slave, before negotiating connections at both the Link Manager and L2CAP layers. All this essential connection process takes place before actually sending data.

CSR noted that while this overhead is essential for standard Bluetooth carrying more complex data protocols, it does slow down the connection. The company confirmed its dual-mode (Bluetooth + ULP Bluetooth) silicon would be available during this year.

- John Walko
EE Times Europe