diff options
Diffstat (limited to 'gr-trellis/src/lib/fsm.cc')
| -rw-r--r-- | gr-trellis/src/lib/fsm.cc | 51 |
1 files changed, 49 insertions, 2 deletions
diff --git a/gr-trellis/src/lib/fsm.cc b/gr-trellis/src/lib/fsm.cc index 50598a94c..550674ad5 100644 --- a/gr-trellis/src/lib/fsm.cc +++ b/gr-trellis/src/lib/fsm.cc @@ -170,7 +170,7 @@ fsm::fsm(int k, int n, const std::vector<int> &G) for(int s=0;s<d_S;s++) { - dec2bases(s,bases_x,sx); // split s into k values, each representing on of the k shift registers + dec2bases(s,bases_x,sx); // split s into k values, each representing one of the k shift registers //printf("state = %d \nstates = ",s); //for(int j=0;j<sx.size();j++) printf("%d ",sx[j]); printf("\n"); for(int i=0;i<d_I;i++) { @@ -239,6 +239,53 @@ fsm::fsm(int mod_size, int ch_length) } + + +//###################################################################### +//# Automatically generate an FSM specification describing the +//# the trellis for a CPM with h=K/P (relatively prime), +//# alphabet size M, and frequency pulse duration L symbols +//# +//# This FSM is based on the paper by B. Rimoldi +//# "A decomposition approach to CPM", IEEE Trans. Info Theory, March 1988 +//# See also my own notes at http://www.eecs.umich.edu/~anastas/docs/cpm.pdf +//###################################################################### +fsm::fsm(int P, int M, int L) +{ + d_I=M; + d_S=(int)(pow(1.0*M,1.0*L-1)+0.5)*P; + d_O=(int)(pow(1.0*M,1.0*L)+0.5)*P; + + d_NS.resize(d_I*d_S); + d_OS.resize(d_I*d_S); + int nv; + for(int s=0;s<d_S;s++) { + for(int i=0;i<d_I;i++) { + int s1=s/P; + int v=s%P; + int ns1= (i*(int)(pow(1.0*M,1.0*(L-1))+0.5)+s1)/M; + if (L==1) + nv=(i+v)%P; + else + nv=(s1%M+v)%P; + d_NS[s*d_I+i] = ns1*P+nv; + d_OS[s*d_I+i] = i*d_S+s; + } + } + + generate_PS_PI(); + generate_TM(); +} + + + + + + + + + + //###################################################################### //# Automatically generate an FSM specification describing the //# the joint trellis of fsm1 and fsm2 @@ -419,7 +466,7 @@ void fsm::write_trellis_svg( std::string filename ,int number_stages) //###################################################################### -//# Write trellis specification to a text files, +//# Write trellis specification to a text file, //# in the same format used when reading FSM files //###################################################################### void fsm::write_fsm_txt(std::string filename) |