src/target/trx_toolkit/fake_pm.py

   1 # -*- coding: utf-8 -*-
   2
   3 # TRX Toolkit
   4 # Power measurement emulation
   5 #
   6 # (C) 2017-2018 by Vadim Yanitskiy <axilirator@gmail.com>
   7 #
   8 # All Rights Reserved
   9 #
  10 # This program is free software; you can redistribute it and/or modify
  11 # it under the terms of the GNU General Public License as published by
  12 # the Free Software Foundation; either version 2 of the License, or
  13 # (at your option) any later version.
  14 #
  15 # This program is distributed in the hope that it will be useful,
  16 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 # GNU General Public License for more details.
  19
  20 from random import randint
  21
  22 class FakePM:
  23         """ Power measurement emulation for fake transceivers.
  24
  25         There is no such thing like RF signal level in fake Um-interface,
  26         so we need to emulate this. The main idea is to have a list of
  27         all running and idle transceivers. As soon as a measurement
  28         request is received, FakePM will attempt to find a running
  29         transceiver on a given frequency.
  30
  31         The result of such "measurement" is a random RSSI value
  32         in one of the following ranges:
  33
  34           - trx_min ... trx_max - if at least one TRX was found,
  35           - noise_min ... noise_max - no TRX instances were found.
  36
  37         FIXME: it would be great to average the rate of bursts
  38                and indicated power / attenuation values for all
  39                matching transceivers, so "pure traffic" ARFCNs
  40                would be handled properly.
  41
  42         """
  43
  44         def __init__(self, noise_min, noise_max, trx_min, trx_max):
  45                 # Init list of transceivers
  46                 self.trx_list = []
  47
  48                 # RSSI randomization ranges
  49                 self.noise_min = noise_min
  50                 self.noise_max = noise_max
  51                 self.trx_min = trx_min
  52                 self.trx_max = trx_max
  53
  54         @property
  55         def rssi_noise(self):
  56                 return randint(self.noise_min, self.noise_max)
  57
  58         @property
  59         def rssi_trx(self):
  60                 return randint(self.trx_min, self.trx_max)
  61
  62         def measure(self, freq, fn = None):
  63                 # Iterate over all known transceivers
  64                 for trx in self.trx_list:
  65                         if not trx.running:
  66                                 continue
  67
  68                         # FIXME: we need to know current TDMA frame number here,
  69                         # because some transceivers may use frequency hopping
  70                         if trx.fh is not None and fn is None:
  71                                 continue
  72
  73                         # Match by given frequency
  74                         if trx.get_tx_freq(fn) == freq:
  75                                 return self.rssi_trx
  76
  77                 return self.rssi_noise