DSP vendors are now at a similar crossroads . If they take the narrow view that their business is just digital signal processors, they might go the way of the U.S. rail system. On the other hand, if they see themselves as DSP applications solution providers, where DSPs are only part of a heterogeneous solution, they will continue to thrive.

The reason is simple: Application demands are growing faster than processor performance levels. For example, while 2G cellular systems are well-served by DSP capabilities, 3G solutions are far beyond the reach of DSPs alone. Vendors serious about targeting advanced applications are thus forced to use heterogeneous designs that combine a DSP with other hardware.

Heterogeneous design has many benefits. Even within a typical DSP-intensive communications product, there are many kinds of algorithms whose computational demands vary radically. Data rates, even within a system, can vary by orders of magnitude. Data types are similarly diverse. Expecting one type of architecture-whether a DSP or something else-to address wildly divergent requirements with high efficiency is both naive and futile.

With heterogeneous solutions, designers capitalize on the fact that different implementation technologies are good at different things. And many different things go on inside today's DSP applications, even within such outwardly simple products as cell phones. As more and more DSP-based applications converge in consumer products, the diversity of requirements within those products increases.

The trend was evident at the Embedded Processor Forum, which highlighted three heterogeneous DSP architectures. LSI Logic and Ericsson jointly described a chip integrating two ZSP cores and reconfigurable logic. STMicroelectronics presented a DSP/general-purpose-processor combination. And Texas Instruments showed the C6416, a DSP with two specialized on-chip coprocessors.

The future belongs not to the vendor with the fastest DSP, but to those that skillfully combine multiple implementation technologies in heterogeneous designs tailored to key applications.

Jeff Bier is General Manager of Berkeley Design Technology Inc. (www.bdti.com), a Technology Analysis and Software Development Company. Honah Holmes of BDTI contributed to this column.