New wave dsps

We are, if you are to believe a senior executive from Analog Devices, in the middle of a revolution that is taking us into the third wave of digital signal processing. John Croteau is general manager of Analog’s convergent platforms and services group, itself part of the DSP and System Products division. In his view, the first wave was fuelled by the deregulation of telecommunications, whilst the second wave was powered by the growth of the mobile phone. Now, the third wave of dsp will be driven by what he terms social networking. “If you look at the evolution of the dsp,” he noted, “you’ll see they have been driven by the handset. The evolution started with voice, but has extended to include the iPod.” Croteau’s first wave, telecommunications or enterprise networking, had a number of demanding requirements. Its end products were such devices as digital pbxs, trunk equipment, 10Mbit Ethernet, faxes and modems. Enabling these devices were such techniques as the Internet Protocol, voice compression and multisymbol modems. In Croteau’s opinion, the challenges for dsp at the time were to provide QAM class communications and voice processing from a real time kernel. What dsps needed to meet that challenge were raw performance, single cycle MACs, inner loop optimisations and high bandwidth data fetching. These requirements were met by devices such as the TigerSharc. The second wave focused on mobile devices. “And this moved the focus from QAM to QPSK,” said Croteau. “Before, there was no operating system; now, it’s an exception when you don’t use one. Where the focus was on raw computing performance, the focus has changed to dsp algorithms and this has evolved to include logical control.” But it’s the third wave on which Croteau is now focused and it’s a development that brings specific challenges, which Analog Devices is hoping to meet with a recent expansion to its Blackfin processor range.