Dec_fir - david-macmahon/wiki_convert_test GitHub Wiki
Block: Decimating FIR Filter (dec_fir)
Block Author: Aaron Parsons
Document Author: Aaron Parsons, Ben Blackman
Summary
FIR filter which can handle multiple time samples in parallel and decimates down to 1 time sample. If coefficiencts are symmetric, it will automatically fold before multiplying.
Mask Parameters
| Parameter | Variable | Description |
|---|---|---|
| Number of Parallel Streams | n_inputs | The number of time samples which arrive in parallel. |
| Coefficients | coeff | The FIR coefficients. If this vector is symmetric, the FIR will automatically fold before multiplying. |
| Bit Width Out | n_bits | The number of bits in each real/imag sample of the complex number that is output. |
| Quantization Behavior | quantization | The quantization behavior used in converting to the output bit width. |
| Add Latency | add_latency | The latency of adders/converters. |
| Mult Latency | mult_latency | The latency of multipliers. |
Ports
| Port | Dir | Data Type | Description |
|---|---|---|---|
| sync_in | IN | boolean | Takes an impulse 1 cycle before input is valid. |
| realX | IN | Fix_(n_bits)_(n_bits-1) | Real input X |
| inagX | IN | Fix_(n_bits)_(n_bits-1) | Imaginary input X |
| sync_out | OUT | boolean | Will be high the clock cycle before dout is valid. |
Description
Usage
User specifies the number of parallel streams to be decimated to one
complex number. Inputs are multiplied by the coefficients and added
together to form dout. Bit Width Out specifies the widths of the real
and imaginary components of the complex number to be output (Ex. if Bit
Width Out = 8, then dout will be 16 bits, 8 for the real and imaginary
components).