NX_TRANSPOSE_SYMMETRIC_FIR is part of the NanoXplore DSP IP Cores. It implements a fully programmable parallel N-TAP FIR filter. It supports up to 112 symmetric taps, and high working frequency.
It was developed to take full advantage of the NG-MEDIUM DSP blocks architecture and direct routing chaining features.
Comparing with the previous TRANSPOSE and SYSTOLIC structure, the TRANSPOSE_SYMMETRIC architecture takes advantage of the coefficient symmetry to reduce the amount of the required DSP blocks. In this architecture, the pre-adder is used to combine two data samples before multiplying the result by the coefficients.
The implementation of the NX_TRANSPOSE_SYMMETRIC_FIR requires 1 DSP block per each two taps. No additional logic is required.
The number of DSP blocks is reduced by a factor 2. In a single CGB column, we can then implement an up to 112-tap FIR filter.
All filter parameters are user’s defined. No need to understand about architecture details to get the maximum performance.
The next figure shows the NX_TRANSPOSE_SYMMETRIC_FIR inputs and outputs.
The following is a summary of the features: