qspectrumanalyzer/qspectrumanalyzer/backends/rtl_power_fftw.py

144 lines
5.6 KiB
Python

import subprocess, math, pprint, shlex
from Qt import QtCore
from qspectrumanalyzer.backends import BaseInfo, BasePowerThread
class Info(BaseInfo):
"""rtl_power_fftw device metadata"""
pass
class PowerThread(BasePowerThread):
"""Thread which runs rtl_power_fftw process"""
def setup(self, start_freq, stop_freq, bin_size, interval=10.0, gain=-1,
ppm=0, crop=0, single_shot=False, device=0, sample_rate=2560000):
"""Setup rtl_power_fftw params"""
crop = crop * 100
overlap = crop * 2
freq_range = stop_freq * 1e6 - start_freq * 1e6
min_overhang = sample_rate * overlap * 0.01
hops = math.ceil((freq_range - min_overhang) / (sample_rate - min_overhang))
overhang = (hops * sample_rate - freq_range) / (hops - 1) if hops > 1 else 0
if bin_size > 2800:
bin_size = 2800
bins = math.ceil(sample_rate / (bin_size * 1e3))
crop_freq = sample_rate * crop * 0.01
self.params = {
"start_freq": start_freq,
"stop_freq": stop_freq,
"freq_range": freq_range,
"device": device,
"sample_rate": sample_rate,
"bin_size": bin_size,
"bins": bins,
"interval": interval,
"hops": hops,
"time": interval / hops,
"gain": gain * 10,
"ppm": ppm,
"crop": crop,
"overlap": overlap,
"min_overhang": min_overhang,
"overhang": overhang,
"single_shot": single_shot
}
self.freqs = [self.get_hop_freq(hop) for hop in range(hops)]
self.freqs_crop = [(f[0] + crop_freq, f[1] - crop_freq) for f in self.freqs]
self.databuffer = {"timestamp": [], "x": [], "y": []}
self.databuffer_hop = {"timestamp": [], "x": [], "y": []}
self.hop = 0
self.prev_line = ""
print("rtl_power_fftw params:")
pprint.pprint(self.params)
print()
def get_hop_freq(self, hop):
"""Get start and stop frequency for particular hop"""
start_freq = self.params["start_freq"] * 1e6 + (self.params["sample_rate"] - self.params["overhang"]) * hop
stop_freq = start_freq + self.params["sample_rate"] - (self.params["sample_rate"] / self.params["bins"])
return (start_freq, stop_freq)
def process_start(self):
"""Start rtl_power_fftw process"""
if not self.process and self.params:
settings = QtCore.QSettings()
cmdline = [
settings.value("executable", "rtl_power_fftw"),
"-f", "{}M:{}M".format(self.params["start_freq"],
self.params["stop_freq"]),
"-b", "{}".format(self.params["bins"]),
"-t", "{}".format(self.params["time"]),
"-d", "{}".format(self.params["device"]),
"-r", "{}".format(self.params["sample_rate"]),
"-p", "{}".format(self.params["ppm"]),
]
if self.params["gain"] >= 0:
cmdline.extend(["-g", "{}".format(self.params["gain"])])
if self.params["overlap"] > 0:
cmdline.extend(["-o", "{}".format(self.params["overlap"])])
if not self.params["single_shot"]:
cmdline.append("-c")
additional_params = settings.value("params", Info.additional_params)
if additional_params:
cmdline.extend(shlex.split(additional_params))
self.process = subprocess.Popen(cmdline, stdout=subprocess.PIPE, stderr=subprocess.DEVNULL,
universal_newlines=True)
def parse_output(self, line):
"""Parse one line of output from rtl_power_fftw"""
line = line.strip()
# One empty line => new hop
if not line and self.prev_line:
self.hop += 1
self.databuffer["x"].extend(self.databuffer_hop["x"])
self.databuffer["y"].extend(self.databuffer_hop["y"])
self.databuffer_hop = {"timestamp": [], "x": [], "y": []}
# Two empty lines => new set
elif not line and not self.prev_line:
self.hop = 0
self.data_storage.update(self.databuffer)
self.databuffer = {"timestamp": [], "x": [], "y": []}
# Get timestamp for new hop and set
elif line.startswith("# Acquisition start:"):
timestamp = line.split(":", 1)[1].strip()
if not self.databuffer_hop["timestamp"]:
self.databuffer_hop["timestamp"] = timestamp
if not self.databuffer["timestamp"]:
self.databuffer["timestamp"] = timestamp
# Skip other comments
elif line.startswith("#"):
pass
# Parse frequency and power
elif line[0].isdigit():
freq, power = line.split()
freq, power = float(freq), float(power)
start_freq, stop_freq = self.freqs_crop[self.hop]
# Apply cropping
if freq >= start_freq and freq <= stop_freq:
# Skip overlapping frequencies
if not self.databuffer["x"] or freq > self.databuffer["x"][-1]:
#print(" {:.3f} MHz".format(freq / 1e6))
self.databuffer_hop["x"].append(freq)
self.databuffer_hop["y"].append(power)
else:
#print(" Overlapping {:.3f} MHz".format(freq / 1e6))
pass
else:
#print(" Cropping {:.3f} MHz".format(freq / 1e6))
pass
self.prev_line = line