From eead55af45ddc9b0b38749c69f06ae5071b09847 Mon Sep 17 00:00:00 2001 From: Enes Albay Date: Fri, 23 May 2025 19:35:58 +0300 Subject: [PATCH 42/75] Replace fftSize with more meaningful name num_fft_bins --- host/hackrf-tools/src/hackrf_sweep.c | 84 ++++++++++++++-------------- 1 file changed, 42 insertions(+), 42 deletions(-) diff --git a/host/hackrf-tools/src/hackrf_sweep.c b/host/hackrf-tools/src/hackrf_sweep.c index 992296b4..ef827ac4 100644 --- a/host/hackrf-tools/src/hackrf_sweep.c +++ b/host/hackrf-tools/src/hackrf_sweep.c @@ -192,7 +192,7 @@ bool one_shot = false; bool finite_mode = false; volatile bool sweep_started = false; -int fftSize = 20; +int num_fft_bins = 20; double fft_bin_width; fftwf_complex* fftwIn = NULL; fftwf_complex* fftwOut = NULL; @@ -242,7 +242,7 @@ int rx_callback(hackrf_transfer* transfer) byte_count += transfer->valid_length; buf = (int8_t*) transfer->buffer; - ifft_bins = fftSize * step_count; + ifft_bins = num_fft_bins * step_count; for (j = 0; j < BLOCKS_PER_TRANSFER; j++) { ubuf = (uint8_t*) buf; if (ubuf[0] == 0x7F && ubuf[1] == 0x7F) { @@ -301,28 +301,28 @@ int rx_callback(hackrf_transfer* transfer) continue; } /* copy to fftwIn as floats */ - buf += BYTES_PER_BLOCK - (fftSize * 2); - for (i = 0; i < fftSize; i++) { + buf += BYTES_PER_BLOCK - (num_fft_bins * 2); + for (i = 0; i < num_fft_bins; i++) { fftwIn[i][0] = buf[i * 2] * window[i] * 1.0f / 128.0f; fftwIn[i][1] = buf[i * 2 + 1] * window[i] * 1.0f / 128.0f; } - buf += fftSize * 2; + buf += num_fft_bins * 2; fftwf_execute(fftwPlan); - for (i = 0; i < fftSize; i++) { - pwr[i] = logPower(fftwOut[i], 1.0f / fftSize); + for (i = 0; i < num_fft_bins; i++) { + pwr[i] = logPower(fftwOut[i], 1.0f / num_fft_bins); } if (binary_output) { record_length = - 2 * sizeof(band_edge) + (fftSize / 4) * sizeof(float); + 2 * sizeof(band_edge) + (num_fft_bins / 4) * sizeof(float); fwrite(&record_length, sizeof(record_length), 1, outfile); band_edge = frequency; fwrite(&band_edge, sizeof(band_edge), 1, outfile); band_edge = frequency + DEFAULT_SAMPLE_RATE_HZ / 4; fwrite(&band_edge, sizeof(band_edge), 1, outfile); - fwrite(&pwr[1 + (fftSize * 5) / 8], + fwrite(&pwr[1 + (num_fft_bins * 5) / 8], sizeof(float), - fftSize / 4, + num_fft_bins / 4, outfile); fwrite(&record_length, sizeof(record_length), 1, outfile); @@ -330,25 +330,25 @@ int rx_callback(hackrf_transfer* transfer) fwrite(&band_edge, sizeof(band_edge), 1, outfile); band_edge = frequency + (DEFAULT_SAMPLE_RATE_HZ * 3) / 4; fwrite(&band_edge, sizeof(band_edge), 1, outfile); - fwrite(&pwr[1 + fftSize / 8], sizeof(float), fftSize / 4, outfile); + fwrite(&pwr[1 + num_fft_bins / 8], sizeof(float), num_fft_bins / 4, outfile); } else if (ifft_output) { ifft_idx = (uint32_t) round( (frequency - (uint64_t) (FREQ_ONE_MHZ * frequencies[0])) / fft_bin_width); ifft_idx = (ifft_idx + ifft_bins / 2) % ifft_bins; - for (i = 0; (fftSize / 4) > i; i++) { + for (i = 0; (num_fft_bins / 4) > i; i++) { ifftwIn[ifft_idx + i][0] = - fftwOut[i + 1 + (fftSize * 5) / 8][0]; + fftwOut[i + 1 + (num_fft_bins * 5) / 8][0]; ifftwIn[ifft_idx + i][1] = - fftwOut[i + 1 + (fftSize * 5) / 8][1]; + fftwOut[i + 1 + (num_fft_bins * 5) / 8][1]; } - ifft_idx += fftSize / 2; + ifft_idx += num_fft_bins / 2; ifft_idx %= ifft_bins; - for (i = 0; (fftSize / 4) > i; i++) { + for (i = 0; (num_fft_bins / 4) > i; i++) { ifftwIn[ifft_idx + i][0] = - fftwOut[i + 1 + (fftSize / 8)][0]; + fftwOut[i + 1 + (num_fft_bins / 8)][0]; ifftwIn[ifft_idx + i][1] = - fftwOut[i + 1 + (fftSize / 8)][1]; + fftwOut[i + 1 + (num_fft_bins / 8)][1]; } } else { time_t time_stamp_seconds = usb_transfer_time.tv_sec; @@ -361,11 +361,11 @@ int rx_callback(hackrf_transfer* transfer) (uint64_t) (frequency), (uint64_t) (frequency + DEFAULT_SAMPLE_RATE_HZ / 4), fft_bin_width, - fftSize); - for (i = 0; (fftSize / 4) > i; i++) { + num_fft_bins); + for (i = 0; (num_fft_bins / 4) > i; i++) { fprintf(outfile, ", %.2f", - pwr[i + 1 + (fftSize * 5) / 8]); + pwr[i + 1 + (num_fft_bins * 5) / 8]); } fprintf(outfile, "\n"); fprintf(outfile, @@ -375,9 +375,9 @@ int rx_callback(hackrf_transfer* transfer) (uint64_t) (frequency + (DEFAULT_SAMPLE_RATE_HZ / 2)), (uint64_t) (frequency + ((DEFAULT_SAMPLE_RATE_HZ * 3) / 4)), fft_bin_width, - fftSize); - for (i = 0; (fftSize / 4) > i; i++) { - fprintf(outfile, ", %.2f", pwr[i + 1 + (fftSize / 8)]); + num_fft_bins); + for (i = 0; (num_fft_bins / 4) > i; i++) { + fprintf(outfile, ", %.2f", pwr[i + 1 + (num_fft_bins / 8)]); } fprintf(outfile, "\n"); } @@ -536,7 +536,7 @@ int main(int argc, char** argv) case 'w': result = parse_u32(optarg, &requested_fft_bin_width); - fftSize = DEFAULT_SAMPLE_RATE_HZ / requested_fft_bin_width; + num_fft_bins = DEFAULT_SAMPLE_RATE_HZ / requested_fft_bin_width; break; case 'W': @@ -657,7 +657,7 @@ int main(int argc, char** argv) * for interleaved mode. With our fixed sample rate of 20 Msps, that * results in a maximum bin width of 5000000 Hz. */ - if (4 > fftSize) { + if (4 > num_fft_bins) { fprintf(stderr, "argument error: FFT bin width (-w) must be no more than 5000000\n"); return EXIT_FAILURE; @@ -667,11 +667,11 @@ int main(int argc, char** argv) * The maximum number of FFT bins we support is equal to the number of * samples in a block. Each block consists of 16384 bytes minus 10 * bytes for the frequency header, leaving room for 8187 two-byte - * samples. As we pad fftSize up to the next odd multiple of four, this - * makes our maximum supported fftSize 8180. With our fixed sample + * samples. As we pad num_fft_bins up to the next odd multiple of four, this + * makes our maximum supported num_fft_bins 8180. With our fixed sample * rate of 20 Msps, that results in a minimum bin width of 2445 Hz. */ - if (8180 < fftSize) { + if (8180 < num_fft_bins) { fprintf(stderr, "argument error: FFT bin width (-w) must be no less than 2445\n"); return EXIT_FAILURE; @@ -681,19 +681,19 @@ int main(int argc, char** argv) * number of FFT bins is equal to an odd multiple of four. * (e.g. 4, 12, 20, 28, 36, . . .) */ - while ((fftSize + 4) % 8) { - fftSize++; + while ((num_fft_bins + 4) % 8) { + num_fft_bins++; } - fft_bin_width = (double) DEFAULT_SAMPLE_RATE_HZ / fftSize; - fftwIn = (fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex) * fftSize); - fftwOut = (fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex) * fftSize); + fft_bin_width = (double) DEFAULT_SAMPLE_RATE_HZ / num_fft_bins; + fftwIn = (fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex) * num_fft_bins); + fftwOut = (fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex) * num_fft_bins); fftwPlan = - fftwf_plan_dft_1d(fftSize, fftwIn, fftwOut, FFTW_FORWARD, fftw_plan_type); - pwr = (float*) fftwf_malloc(sizeof(float) * fftSize); - window = (float*) fftwf_malloc(sizeof(float) * fftSize); - for (i = 0; i < fftSize; i++) { - window[i] = (float) (0.5f * (1.0f - cos(2 * M_PI * i / (fftSize - 1)))); + fftwf_plan_dft_1d(num_fft_bins, fftwIn, fftwOut, FFTW_FORWARD, fftw_plan_type); + pwr = (float*) fftwf_malloc(sizeof(float) * num_fft_bins); + window = (float*) fftwf_malloc(sizeof(float) * num_fft_bins); + for (i = 0; i < num_fft_bins; i++) { + window[i] = (float) (0.5f * (1.0f - cos(2 * M_PI * i / (num_fft_bins - 1)))); } /* Execute the plan once to make sure it's ready to go when real @@ -807,11 +807,11 @@ int main(int argc, char** argv) if (ifft_output) { ifftwIn = (fftwf_complex*) fftwf_malloc( - sizeof(fftwf_complex) * fftSize * step_count); + sizeof(fftwf_complex) * num_fft_bins * step_count); ifftwOut = (fftwf_complex*) fftwf_malloc( - sizeof(fftwf_complex) * fftSize * step_count); + sizeof(fftwf_complex) * num_fft_bins * step_count); ifftwPlan = fftwf_plan_dft_1d( - fftSize * step_count, + num_fft_bins * step_count, ifftwIn, ifftwOut, FFTW_BACKWARD, -- 2.47.3