GNU Radio 3.7.2git-29-g7516b6dd C++ API
channel_model2.h
Go to the documentation of this file.
1
/* -*- c++ -*- */
2
/*
3
* Copyright 2009,2012,2013 Free Software Foundation, Inc.
4
*
5
* This file is part of GNU Radio
6
*
7
* GNU Radio is free software; you can redistribute it and/or modify
8
* it under the terms of the GNU General Public License as published by
9
* the Free Software Foundation; either version 3, or (at your option)
10
* any later version.
11
*
12
* GNU Radio is distributed in the hope that it will be useful,
13
* but WITHOUT ANY WARRANTY; without even the implied warranty of
14
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15
* GNU General Public License for more details.
16
*
17
* You should have received a copy of the GNU General Public License
18
* along with GNU Radio; see the file COPYING. If not, write to
19
* the Free Software Foundation, Inc., 51 Franklin Street,
20
* Boston, MA 02110-1301, USA.
21
*/
22
23
#ifndef INCLUDED_CHANNELS_CHANNEL_MODEL2_H
24
#define INCLUDED_CHANNELS_CHANNEL_MODEL2_H
25
26
#include <
gnuradio/channels/api.h
>
27
#include <
gnuradio/hier_block2.h
>
28
#include <
gnuradio/types.h
>
29
30
namespace
gr {
31
namespace
channels {
32
33
/*!
34
* \brief channel model2
35
* \ingroup channel_models_blk
36
*
37
* \details
38
* This block implements a basic channel model simulator that can
39
* be used to help evaluate, design, and test various signals,
40
* waveforms, and algorithms.
41
*
42
* This model allows the user to set the voltage of an AWGN noise
43
* source, an initial timing offset, and a noise seed to randomize
44
* the AWGN noise source.
45
*
46
* Multipath can be approximated in this model by using a FIR
47
* filter representation of a multipath delay profile.
48
*
49
* Unlike gr::channels::channel_model, this block is designed to
50
* enable time-varying frequency and timing offsets.
51
* * Port 0: input signal to be run through the channel.
52
* * Port 1: frequency function. A constant value between -0.5 and
53
* 0.5 here will turn into a constant frequency offset
54
* from -fs/2 to fs/2 (where fs is the sample rate).
55
* * Port 2: timing offset function. Sets the resampling rate of
56
* the channel model. A constant value here produces
57
* that value as the timing offset, so a constant 1.0
58
* input stream is the same as not having a timing
59
* offset.
60
*
61
* Since the models for frequency and timing offset may vary and
62
* what we are trying to model may be different for different
63
* simulations, we provide the time-varying nature as an input
64
* function that is user-defined. If only constant frequency and
65
* timing offsets are required, it is easier and less expensive to
66
* use gr::channels::channel_model.
67
*/
68
class
CHANNELS_API
channel_model2
:
virtual
public
hier_block2
69
{
70
public
:
71
// gr::channels::channel_model2::sptr
72
typedef
boost::shared_ptr<channel_model2>
sptr
;
73
74
/*! \brief Build the channel simulator.
75
*
76
* \param noise_voltage The AWGN noise level as a voltage (to be
77
* calculated externally to meet, say, a
78
* desired SNR).
79
* \param epsilon The initial sample timing offset to emulate the
80
* different rates between the sample clocks of
81
* the transmitter and receiver. 1.0 is no difference.
82
* \param taps Taps of a FIR filter to emulate a multipath delay profile.
83
* \param noise_seed A random number generator seed for the noise source.
84
*/
85
static
sptr
make(
double
noise_voltage=0.0,
86
double
epsilon=1.0,
87
const
std::vector<gr_complex> &
taps
=std::vector<gr_complex>(1,1),
88
double
noise_seed=0);
89
90
virtual
void
set_noise_voltage(
double
noise_voltage) = 0;
91
virtual
void
set_taps(
const
std::vector<gr_complex> &
taps
) = 0;
92
virtual
void
set_timing_offset(
double
epsilon) = 0;
93
94
virtual
double
noise_voltage()
const
= 0;
95
virtual
std::vector<gr_complex>
taps
()
const
= 0;
96
virtual
double
timing_offset()
const
= 0;
97
};
98
99
}
/* namespace channels */
100
}
/* namespace gr */
101
102
#endif
/* INCLUDED_CHANNELS_CHANNEL_MODEL2_H */
gnuradio
gr-channels
include
gnuradio
channels
channel_model2.h
Generated by
1.8.1.2