% BluetoothTransmitter Class
%
% Copyright 2008-2009 The MathWorks, Inc
% C++ Code
%{
#include <math.h>
#include "bluetooth.h"
#include "util.h"
class BluetoothTransmitter : public Transmitter {
%}
classdef BluetoothTransmitter < Transmitter
properties (GetAccess='private', SetAccess='private')
% C++ Code
%{
bool m_prev; // previous bit modulated
double m_hf; // modulation index
// Used in implementation of GFSK modulation scheme
%}
m_prev; % Boolean previous bit modulated
m_hf; % Double modulation index
end
properties (Constant=true, GetAccess='private', SetAccess='private')
% C++ Code
%{
// Modulation
// Gaussian filter coefficients for modulator. Ns=44 samples per bit
//static
const double BluetoothTransmitter::s_qcoef[2*Ns] =
{.0003384128078, .0007483472705, .001241740730, .001831809714, // [0..3]
.002533043604, .003361167254, .004333069131, .005466692340, // [4..7]
.006780887010, .008295223730, .01002976939, .01200482814, // [8..11]
.01424065196, .01675712682, .01957344200, .02270775110, // [12..15]
.02617683454, .02999577350, .03417764580, .03873325341, // [16..19]
.04367089078, .04899616180, .05471185145, .06081785680, // [20..23]
.06731117780, .07418596970, .08143365250, .08904307290, // [24..27]
.09700071245, .1052909327 , .1138962464 , .1227976077, // [28..31]
.1319747047, .1414062494, .1510702515, .1609442679, // [32..35]
.1710056206, .1812315788, .1915994984, .2020869202, // [36..39]
.2126716262, .2233316570, .2340452932, .2447910090, // [40..43]
.2555474036, .2662931193, .2770067556, .2876667864, // [44..47]
.2982514925, .3087389142, .3191068338, .3293327920, // [48..51]
.3393941448, .3492681611, .3589321632, .3683637078, // [52..55]
.3775408048, .3864421662, .3950474800, .4033377002, // [56..59]
.4112953398, .4189047602, .4261524430, .4330272350, // [60..63]
.4395205560, .4456265612, .4513422510, .4566675220, // [64..67]
.4616051594, .4661607670, .4703426394, .4741615782, // [68..71]
.4776306617, .4807649708, .4835812860, .4860977608, // [72..75]
.4883335846, .4903086434, .4920431890, .4935575258, // [76..79]
.4948717204, .4960053436, .4969772456, .4978053692, // [80..83]
.4985066031, .4990966721, .4995900656, .5000000000}; // [84..87]
%}
s_qcoef= [.0003384128078; .0007483472705; .001241740730; .001831809714; % [0..3]
.002533043604; .003361167254; .004333069131; .005466692340; % [4..7]
.006780887010; .008295223730; .01002976939; .01200482814; % [8..11]
.01424065196; .01675712682; .01957344200; .02270775110; % [12..15]
.02617683454; .02999577350; .03417764580; .03873325341; % [16..19]
.04367089078; .04899616180; .05471185145; .06081785680; % [20..23]
.06731117780; .07418596970; .08143365250; .08904307290; % [24..27]
.09700071245; .1052909327 ; .1138962464 ; .1227976077; % [28..31]
.1319747047; .1414062494; .1510702515; .1609442679; % [32..35]
.1710056206; .1812315788; .1915994984; .2020869202; % [36..39]
.2126716262; .2233316570; .2340452932; .2447910090; % [40..43]
.2555474036; .2662931193; .2770067556; .2876667864; % [44..47]
.2982514925; .3087389142; .3191068338; .3293327920; % [48..51]
.3393941448; .3492681611; .3589321632; .3683637078; % [52..55]
.3775408048; .3864421662; .3950474800; .4033377002; % [56..59]
.4112953398; .4189047602; .4261524430; .4330272350; % [60..63]
.4395205560; .4456265612; .4513422510; .4566675220; % [64..67]
.4616051594; .4661607670; .4703426394; .4741615782; % [68..71]
.4776306617; .4807649708; .4835812860; .4860977608; % [72..75]
.4883335846; .4903086434; .4920431890; .4935575258; % [76..79]
.4948717204; .4960053436; .4969772456; .4978053692; % [80..83]
.4985066031; .4990966721; .4995900656; .5000000000]; % [84..87]
end
methods
function hObj=BluetoothTransmitter(varargin)
% C++ Code
%{
BluetoothTransmitter(double hf=1./3., double phase_shift=0.0); from header
BluetoothTransmitter::BluetoothTransmitter(double hf,
double phase_shift)
{
m_bitrate = 1; // 1 Mb/s
m_hf = hf; // Modulation index
m_prev = false; // Previous bit transmitted
setPhase(phase_shift); // Current phase
%}
hf=getArg(1,varargin,1/3);
phase_shift=getArg(2,varargin,0);
hObj.m_bitrate = 1; % 1 Mb/s
hObj.m_hf = hf; % Modulation index
hObj.m_prev = 0; % Previous bit transmitted
hObj.m_phase=phase_shift; % Current phase
end
% C++ Code
%{
BluetoothTransmitter::BluetoothTransmitter(BluetoothTransmitter& txbt)
{
m_bitrate = 1;
m_hf=txbt.m_hf;
m_prev = txbt.m_prev;
setPhase(txbt.getPhase());
}
Copy constructor not required
//virtual
BluetoothTransmitter::~BluetoothTransmitter() {
}
Destructor not required
%}
function out=transmit(hObj,input,df)
% C++ Code
%{
// virtual
Signal
BluetoothTransmitter::transmit(const Bits& input,
double df) {
return modulate(input, df);
}
%}
out=modulate(hObj,input,df);
end
function reset(hObj)
% C++ Code
%{
//virtual
void
BluetoothTransmitter::reset() {
setPhase(0.0);
m_prev=false;
}
%}
hObj.m_phase=0; % Just use public property access
hObj.m_prev=0;
end
function modOut=modulate(hObj,input, df)
% Modulate using GFSK
% C++ Code
%{
Signal modulate(const Bits& input, double df=0);
Signal
BluetoothTransmitter::modulate(const Bits& input, double df) {
Signal modOut(Ns * input.size());
int offset = 0;
double phase=getPhase();
%}
Ns=constants.Ns; % Get constants now for use later
twopi=constants.twopi;
offset=0;
phase=hObj.m_phase;
modOut=zeros(Ns*length(input),1);
% C++ Code
%{
for (int i=0; i<input.size(); ++i) {
for(int j=0; j<Ns; ++j) {
double tt=twopi*df*(j+Ns*i)/((double)Ns);
if (tt>twopi) { tt=fmod(tt,twopi); }
double state = qsign(input[i])*s_qcoef[j] +
qsign(m_prev)*s_qcoef[j+Ns] + phase;
modOut[offset+j] = exp(Sample(0.0,twopi* (m_hf * state)+tt));
} // end j
%}
jj=(0:Ns-1)'; % Vectorizatrion replaces loop
for ii=0:length(input)-1
% Vectorized using jj
tt=twopi*df*(jj+Ns*ii)/Ns;
found=tt>twopi;
tt(found)=mod(tt(found),twopi);
state = (1-2*input(ii+1))*hObj.s_qcoef(jj+1) +... % Avoid function call
(1-2*hObj.m_prev)*hObj.s_qcoef(jj+1+ Ns) + phase;
modOut(offset+jj+1)= exp(j*(twopi* (hObj.m_hf * state)+tt));
% C++ Code
%{
// Update phase and previous bit value
phase += (m_prev ? -0.5 : 0.5);
m_prev = input[i];
offset += Ns;
} end i
setPhase(phase);
return modOut;
}
%}
% Update phase and previous bit value
if hObj.m_prev
phase = phase-0.5;
else
phase= phase+.5;
end
hObj.m_prev = input(ii+1);
offset = offset+Ns;
end
hObj.m_phase=phase;
end
end
end
function out=qsign(bval)
% Not used. In lined instead
% C++ Code
%{
static inline double qsign(bool bval) { return ((bval) ? -1.0 : 1.0); }
%}
if bval
out=-1;
else
out =1;
end
end
