March 16, 2005 -- RF Engines, Ltd. (RFEL) has signed a contract with one of the leading mobile communications companies to supply high speed signal processing cores. The company in question, which prefers not to be named at this point, is incorporating the cores in its research and development programme. The RFEL designs are based on the high specification Matrix range of mixed radix Discrete Fourier Transform (DFT) cores, which are being integrated to produce a non-power-of-two filter bank. Precise details of the design cannot be released at this time.

The Matrix family of core designs are built around a set of different prime length DFT (Discrete Fourier Transform) cores. When these different cores are combined, they allow non ‘power-of-two’ FFTs to be configured that exactly match the number of points required for the application. This offers greater flexibility over the standard FFT algorithm, which is limited to power-of-two lengths.

As an example, in a recent design that required 1872 channels to be precisely extracted from a spectrum bandwidth in excess of 40MHz, 2-point, 3-point and 13-point DFT cores were integrated to produce this exact length FFT. A simple 2048 point FFT would not have been able to meet the channel spacing and sample rate requirements for this application. The design fitted comfortably within a Xilinx Virtex Pro50 FPGA with room to spare.