Right up there with phased arrays in importance as a key radio technology direction is software defined radio, or SDR. The idea here is to replace dedicated hardware implementations of specific radios with their software equivalent, running on really fast processors like digital signal processors (DSPs, which, if you’ve not heard of these, are simply very powerful microprocessors optimized for mathematical operations). The benefits of this approach are many: flexibility, component reuse across designs (thereby lowering engineering expense), being able to fix bugs and add features in the field, longer shelf and useful lives for specific implementations, and lower cost-to-solution, among others. And so are the challenges: component cost and size, heat dissipation, all that software, and especially power consumption. So while SDR is widely applied in base-station designs today, a bigger opportunity, and a bigger challenge, is in getting it into handsets. My forecast for some time has been production SDR-based handsets in 2012 or thereabouts. But, as I just found out, this could happen sooner.
I spoke with Bitwave Semiconductor this week, and they’ve been quietly working on the radio part of the problem for some time (I’ll get to the other part in a moment). By “radio part”, that means the front end, also called the transceiver. Bitwave will soon ship their 1102 product which is a highly-programmable component indeed – it operates over 700 MHz. to 3.8 GHz. (covering everything from cellular to offshore fixed WiMAX bands), channel bandwidths from 25 KHz. To 20 MHz. (GSM to WCDMA/HSPA/LTE), and has power consumption low enough to challenge current implementations and to be used in some handset designs. Bitwave mentioned to me that this part may not be the volume handset implementation (that’s next), but it’s an amazing start – and, in terms of availability, well ahead of my forecast.
The other part, BTW, is called the baseband. This does modulation and demodulation (remember the term MODEM? Radios are modems…), and is already well-suited to SDR techniques. Have a look (just for example) at picoChip for DSP hardware, and Vanu Inc. for SDR software. Add supercapacitors for power management, and the pieces are rapidly falling into place.
Still, the real challenge is to get a handset vendor to put all of these pieces together and to get products that you and I can buy on the shelf. But 2012 is now looking like a sure thing to accomplish this goal, if not a little bit sooner.
