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Too many radios! - CSR throws a free FM receiver into Bluetooth silicon

Here's a problem for phone designers: if you want to include FM radio in the phone, where do you put it? In the phone? or in the Bluetooth stereo headset? With the new CSR BlueCore5-FM silicon, being demoed at CTIA in Las Vegas this week, you could do both.

The CTIA show will swamp the PR wires over the next week, from 5-7 April, and surprisingly few exhibitors have apparently twigged the importance of telling delegates in advance what will be on show. No such accusation can be aimed at Cambridge Silicon Radio, who actually announced the new product back in September last year, and who are now boosting the signal for the Vegas show.

And what they have, is a single piece of silicon that does both Bluetooth and FM radios - and what is more, does them both together.

The obvious use will be demonstrated in Vegas.  "The first demonstration will show that the FM and Bluetooth radios can work simultaneously without interference or degradation in performance," says CSR. "The FM radio will play through either stereo speakers or a wired headset whilst the EDR Bluetooth link will transfer a large file from the host to another Bluetooth-enabled device."

But the second demo is the teaser: "The second will show stereo music received by the FM radio being successfully streamed over a Bluetooth connection to a pair of stereo headphones." And of course, as soon as you see that you can do that, you start to wonder: why put the FM radio in the phone? Why not put it straight into the headphones? That way, you stop draining the important battery in the phone!

The official PR announcement says: "BlueCore5-FM is the first product from CSR's roadmap to integrate broadcast technology into single-chip Bluetooth devices. By integrating the FM radio with Bluetooth silicon, handset designers will be able to offer this feature using less space on the circuit board (PCB), fewer analogue components and at lower cost to the bill of materials (BOM)."

BlueCore5-FM offers data transfer rates of up to 3Mb/s and low power 1.8V operation. A fully featured FM radio is also incorporated on the compact WLCSP or 6x6mm VFBGA package. The FM radio is integrated using a low IF receiver architecture, followed by a DSP (digital signal processor) based demodulator with interference suppression to ensure there is no conflict between the FM and Bluetooth radios.

CSR will demonstrate the capabilities of its BlueCore5-FM technology at CTIA, Las Vegas, from 5 to 7 April 2006, Hall N3, Stand 4725.

Tags: Bluetooth, stereo headset