From: drowe67 <drowe67@01035d8c-6547-0410-b346-abe4f91aad63>
Date: Sun, 24 Mar 2013 05:49:45 +0000 (+0000)
Subject: support for setting carrier separation
X-Git-Url: http://git.whiteaudio.com/gitweb/?a=commitdiff_plain;h=56b9f359f73325d4d1d5dc944d9e2a977e7788cc;p=freetel-svn-tracking.git

support for setting carrier separation

git-svn-id: https://svn.code.sf.net/p/freetel/code@1225 01035d8c-6547-0410-b346-abe4f91aad63
---

diff --git a/codec2-dev/src/codec2_fdmdv.h b/codec2-dev/src/codec2_fdmdv.h
index 1d9db7d2..543b4d04 100644
--- a/codec2-dev/src/codec2_fdmdv.h
+++ b/codec2-dev/src/codec2_fdmdv.h
@@ -94,7 +94,9 @@ struct FDMDV * CODEC2_WIN32SUPPORT fdmdv_create(int Nc);
 void           CODEC2_WIN32SUPPORT fdmdv_destroy(struct FDMDV *fdmdv_state);
 void           CODEC2_WIN32SUPPORT fdmdv_use_old_qpsk_mapping(struct FDMDV *fdmdv_state);
 int            CODEC2_WIN32SUPPORT fdmdv_bits_per_frame(struct FDMDV *fdmdv_state);
-    
+float          CODEC2_WIN32SUPPORT fdmdv_get_fsep(struct FDMDV *fdmdv_state);
+void           CODEC2_WIN32SUPPORT fdmdv_set_fsep(struct FDMDV *fdmdv_state, float fsep);
+
 void           CODEC2_WIN32SUPPORT fdmdv_mod(struct FDMDV *fdmdv_state, COMP tx_fdm[], int tx_bits[], int *sync_bit);
 void           CODEC2_WIN32SUPPORT fdmdv_demod(struct FDMDV *fdmdv_state, int rx_bits[], int *reliable_sync_bit, COMP rx_fdm[], int *nin);
     
diff --git a/codec2-dev/src/fdmdv.c b/codec2-dev/src/fdmdv.c
index b1e76fa5..880cabb2 100644
--- a/codec2-dev/src/fdmdv.c
+++ b/codec2-dev/src/fdmdv.c
@@ -125,7 +125,6 @@ struct FDMDV * CODEC2_WIN32SUPPORT fdmdv_create(int Nc)
 {
     struct FDMDV *f;
     int           c, i, k;
-    float         carrier_freq;
 
     assert(NC == FDMDV_NC_MAX);  /* check public and private #defines match */
     assert(Nc <= NC);
@@ -184,22 +183,9 @@ struct FDMDV * CODEC2_WIN32SUPPORT fdmdv_create(int Nc)
 	    f->rx_baseband_mem_timing[c][k].real = 0.0;
 	    f->rx_baseband_mem_timing[c][k].imag = 0.0;
 	}
-  }
-    
-    /* Set up frequency of each carrier */
-
-    for(c=0; c<Nc/2; c++) {
-	carrier_freq = (-Nc/2 + c)*FSEP + FDMDV_FCENTRE;
-	f->freq[c].real = cos(2.0*PI*carrier_freq/FS);
- 	f->freq[c].imag = sin(2.0*PI*carrier_freq/FS);
-    }
-
-    for(c=Nc/2; c<Nc; c++) {
-	carrier_freq = (-Nc/2 + c + 1)*FSEP + FDMDV_FCENTRE;
-	f->freq[c].real = cos(2.0*PI*carrier_freq/FS);
- 	f->freq[c].imag = sin(2.0*PI*carrier_freq/FS);
     }
-	
+    
+    fdmdv_set_fsep(f, FSEP);
     f->freq[Nc].real = cos(2.0*PI*FDMDV_FCENTRE/FS);
     f->freq[Nc].imag = sin(2.0*PI*FDMDV_FCENTRE/FS);
 
@@ -305,6 +291,32 @@ void CODEC2_WIN32SUPPORT fdmdv_get_test_bits(struct FDMDV *f, int tx_bits[])
     }
  }
 
+float CODEC2_WIN32SUPPORT fdmdv_get_fsep(struct FDMDV *f)
+{
+    return f->fsep;
+}
+
+void CODEC2_WIN32SUPPORT fdmdv_set_fsep(struct FDMDV *f, float fsep) {
+    int   c;
+    float carrier_freq;
+
+    f->fsep = fsep;
+    /* Set up frequency of each carrier */
+
+    for(c=0; c<f->Nc/2; c++) {
+	carrier_freq = (-f->Nc/2 + c)*f->fsep + FDMDV_FCENTRE;
+	f->freq[c].real = cos(2.0*PI*carrier_freq/FS);
+ 	f->freq[c].imag = sin(2.0*PI*carrier_freq/FS);
+    }
+
+    for(c=f->Nc/2; c<f->Nc; c++) {
+	carrier_freq = (-f->Nc/2 + c + 1)*f->fsep + FDMDV_FCENTRE;
+	f->freq[c].real = cos(2.0*PI*carrier_freq/FS);
+ 	f->freq[c].imag = sin(2.0*PI*carrier_freq/FS);
+    }
+}
+
+
 /*---------------------------------------------------------------------------*\
                                                        
   FUNCTION....: bits_to_dqpsk_symbols()	     
diff --git a/codec2-dev/src/fdmdv_internal.h b/codec2-dev/src/fdmdv_internal.h
index 34ff7bde..e9b355d4 100644
--- a/codec2-dev/src/fdmdv_internal.h
+++ b/codec2-dev/src/fdmdv_internal.h
@@ -50,7 +50,7 @@
 #define NSYM                     6  /* number of symbols to filter over                                     */
 #define NFILTER            (NSYM*M) /* size of tx/rx filters at sample rate M                               */
 
-#define FSEP                    75  /* Separation between carriers (Hz)                                     */
+#define FSEP                    75  /* Default separation between carriers (Hz)                             */
 
 #define NT                       5  /* number of symbols we estimate timing over                            */
 #define P                        4  /* oversample factor used for initial rx symbol filtering               */
@@ -77,7 +77,8 @@
 
 struct FDMDV {
 
-    int Nc;           
+    int   Nc;           
+    float fsep;
 
     /* test data (test frame) states */