diff options
Diffstat (limited to 'src/main.rs')
| -rw-r--r-- | src/main.rs | 44 |
1 files changed, 26 insertions, 18 deletions
diff --git a/src/main.rs b/src/main.rs index 54f7171..e35062e 100644 --- a/src/main.rs +++ b/src/main.rs @@ -69,8 +69,8 @@ impl<T> BufferDumper<T> { } struct DDS { - trig_table_quadrature: Vec<i8>, - trig_table_inphase: Vec<i8>, + trig_table_carrier_1: Vec<i8>, + trig_table_carrier_2: Vec<i8>, /* instantaneous phase */ phase: u32, @@ -83,23 +83,23 @@ struct DDS { } impl DDS { - fn init(samp_rate: f32, freq: f32, phase: f32, waveform: Waveform) -> Self { - let mut trig_table_inphase = Vec::with_capacity(TRIG_TABLE_LEN); - let mut trig_table_quadrature = Vec::with_capacity(TRIG_TABLE_LEN); + fn init(samp_rate: f32, freq: f32, carrier_phase_delta: f32, waveform: Waveform) -> Self { + let mut trig_table_carrier_1 = Vec::with_capacity(TRIG_TABLE_LEN); + let mut trig_table_carrier_2 = Vec::with_capacity(TRIG_TABLE_LEN); let incr = 1.0f32 / TRIG_TABLE_LEN as f32; for i in 0..TRIG_TABLE_LEN { - let inphase = f32::cos(incr * i as f32 * 2.0 * PI) * 127.0; - let quadrature = f32::sin(incr * i as f32 * 2.0 * PI) * 127.0; + let c1 = f32::sin((incr * i as f32 + carrier_phase_delta/2.0) * 2.0 * PI) * 127.0; + let c2 = f32::sin((incr * i as f32 - carrier_phase_delta/2.0) * 2.0 * PI) * 127.0; match waveform { Waveform::Sine => { - trig_table_inphase.push(f32::round(inphase) as i8); - trig_table_quadrature.push(f32::round(quadrature) as i8); + trig_table_carrier_1.push(f32::round(c1) as i8); + trig_table_carrier_2.push(f32::round(c2) as i8); } Waveform::Rect => { - trig_table_inphase.push(if inphase >= 0.0 { 127 } else { -127 }); - trig_table_quadrature.push(if quadrature >= 0.0 { 127 } else { -127 }); + trig_table_carrier_1.push(if c1 >= 0.0 { 127 } else { -127 }); + trig_table_carrier_2.push(if c2 >= 0.0 { 127 } else { -127 }); } } } @@ -107,9 +107,9 @@ impl DDS { let phase_step = (freq / samp_rate) * 2.0 * PI * ANG_INCR; DDS { - trig_table_quadrature, - trig_table_inphase, - phase: f32::round(phase * ANG_INCR) as u32, + trig_table_carrier_1, + trig_table_carrier_2, + phase: 0, phase_step: f32::round(phase_step) as u32, phase_delta: 0, phase_slope: 0, @@ -131,7 +131,8 @@ fn main() { opts.optopt("d", "device-index", "Select device index", "DEVINDEX"); opts.optopt("c", "center-freq", "Center frequency in Hz (default: 1440 kHz)", "FREQ"); opts.optopt("s", "samplerate", "Samplerate in Hz (default: 96 MS/s)", "RATE"); - opts.optopt("m", "mod-index", "Modulation index (default: 0.25)]", "FACTOR"); + opts.optopt("m", "mod-index", "Modulation index (default: 0.25)", "FACTOR"); + opts.optopt("p", "carrier-phase", "Carrier phase difference (default: 90)", "DEGREES"); opts.optopt("i", "input-rate", "Input baseband sample rate (default: 48000 Hz)", "RATE"); opts.optopt("w", "waveform", "(sine|rect) default: rect", "WAVEFORM"); opts.optflag("C", "device-count", "Return FL2K device count and quit"); @@ -183,6 +184,12 @@ fn main() { None => 0.25, }; + let carrier_phase_delta_degrees = match cli_args.opt_str("p") { + Some(s) => s.parse().expect("floating point value"), + None => 90.0, + }; + let carrier_phase_delta = carrier_phase_delta_degrees * PI / 180.0; + let waveform = match cli_args.opt_str("w") { None => Waveform::Rect, Some(w) if w == "sine" => Waveform::Sine, @@ -211,6 +218,7 @@ fn main() { eprintln!("Input rate: {} kHz", (input_rate as f32)/1e3); eprintln!("Samplerate: {} MHz", (samp_rate as f32)/1e6); eprintln!("Center frequency: {} kHz", base_freq/1e3); + eprintln!("Carrier phase d {} deg ({} rad)", carrier_phase_delta_degrees, carrier_phase_delta); let running = Arc::new(AtomicBool::new(true)); @@ -341,7 +349,7 @@ fn main() { // Read PD and PDSLOPE, interpolate to higher rate thread::spawn(move || { - let mut dds = DDS::init(samp_rate as f32, base_freq, 0.0, waveform); + let mut dds = DDS::init(samp_rate as f32, base_freq, carrier_phase_delta, waveform); let mut debug_writer = match output { Output::Debug => Some(BufWriter::new(File::create("debug-dds.csv").expect("create file"))), @@ -367,8 +375,8 @@ fn main() { panic!("Phase IDX out of bounds"); } - out_i.push(dds.trig_table_inphase[phase_idx_i as usize]); - out_q.push(dds.trig_table_quadrature[phase_idx_q as usize]); + out_i.push(dds.trig_table_carrier_1[phase_idx_i as usize]); + out_q.push(dds.trig_table_carrier_2[phase_idx_q as usize]); if let Some(w) = &mut debug_writer { writeln!(w, "{},{},{},{},{}", ix, dds.phase, dds.phase_delta, phase_idx_i, phase_idx_q) |