Single Chip Software Radio
Objective
To develop an ASIC for use in a consumer application, that would be produced in millions of units per year, and yet where future flexibility was required. An ASIC that would provide the client with a low-cost, low-power radio solution for short distance radio applications.
Approach
The design philosophy was to move as much of the RF circuitry into Digital Signal Processing (DSP) and digital hardware as possible. The geometry of the resulting ASIC produced a smaller footprint and was consequently cheaper than the analogue equivalent. To minimise cost Cambridge Consultants' own APE2 Digital Signal Processor design was used, whose low gate count also kept die size to a minimum and reduced power consumption.
Result
A single chip radio solution with low unit cost, low power consumption and a rapid development time that had a design ready for tape-out in just over 6 months.
Benefit
By moving large amounts of traditional RF circuitry into the DSP the ASIC becomes a true software radio. The result is not only a low-power, low-cost ASIC, but the software options create a large degree of flexibility, allowing the same chip to provide new higher baud rates whilst also being compatible with a number of legacy products.