diff --git a/DSP_API/ThumbDV/gmsk_modem.c b/DSP_API/ThumbDV/gmsk_modem.c
index 8b41b68..9060955 100644
--- a/DSP_API/ThumbDV/gmsk_modem.c
+++ b/DSP_API/ThumbDV/gmsk_modem.c
@@ -27,8 +27,9 @@
 /* Demod Section */
 #include "DStarDefines.h"
 #include "gmsk_modem.h"
+#include "common.h"
 
-const float FILTER_COEFFS_TABLE[] = {
+const float DEMOD_COEFFS_TABLE[] = {
     /* 2400 Hz */
     -0.000153959924563F,  0.000000000000000F,  0.000167227768379F,  0.000341615513437F,
      0.000513334449696F,  0.000667493753523F,  0.000783901543032F,  0.000838293462576F,
@@ -57,7 +58,7 @@ const float FILTER_COEFFS_TABLE[] = {
      0.000783901543032F,  0.000667493753523F,  0.000513334449696F,  0.000341615513437F,
      0.000167227768379F,  0.000000000000000F, -0.000153959924563F};
 
-#define FILTER_COEFFS_LENGTH 103U
+#define DEMOD_COEFFS_LENGTH 103U
 
 #define PLLMAX  0x10000U
 #define PLLINC      ( PLLMAX / DSTAR_RADIO_BIT_LENGTH)
@@ -107,4 +108,47 @@ void gmskDemod_reset(GMSK_DEMOD demod )
 /* Mod Section */
 
 
+// Generated by
+// gaussfir(0.5, 2, 10)
+const float MOD_COEFFS_TABLE[] = {
+    6.455906007234699e-014F, 1.037067381285011e-012F, 1.444835156335346e-011F,
+    1.745786683011439e-010F, 1.829471305298363e-009F, 1.662729407135958e-008F,
+    1.310626978701910e-007F, 8.959797186410516e-007F, 5.312253663302771e-006F,
+    2.731624380156465e-005F, 1.218217140199093e-004F, 4.711833994209542e-004F,
+    1.580581180127418e-003F, 4.598383433830095e-003F, 1.160259430889949e-002F,
+    2.539022692626253e-002F, 4.818807833062393e-002F, 7.931844341164322e-002F,
+    1.132322945270602e-001F, 1.401935338024111e-001F, 1.505383695578516e-001F,
+    1.401935338024111e-001F, 1.132322945270601e-001F, 7.931844341164328e-002F,
+    4.818807833062393e-002F, 2.539022692626253e-002F, 1.160259430889949e-002F,
+    4.598383433830090e-003F, 1.580581180127420e-003F, 4.711833994209542e-004F,
+    1.218217140199093e-004F, 2.731624380156465e-005F, 5.312253663302753e-006F,
+    8.959797186410563e-007F, 1.310626978701910e-007F, 1.662729407135958e-008F,
+    1.829471305298363e-009F, 1.745786683011426e-010F, 1.444835156335356e-011F,
+    1.037067381285011e-012F, 6.455906007234699e-014F};
+
+#define MOD_COEFFS_LENGTH 41U
+
+uint32 gmsk_encode(GMSK_MOD mod, BOOL bit, float * buffer, unsigned int length)
+{
+
+    if ( length == DSTAR_RADIO_BIT_LENGTH ) {
+        output(ANSI_RED "Length!= DSTAR_RADIO_BIT_LENGTH" ANSI_WHITE);
+    }
+
+    if (mod->m_invert)
+        bit = !bit;
+
+    uint32 i = 0;
+
+    for (i = 0; i < DSTAR_RADIO_BIT_LENGTH; i++) {
+        if (bit) {
+            buffer[i] = 0;//m_filter.process(-0.5F);
+        } else {
+            buffer[i] = 0;//m_filter.process(0.5F);
+        }
+    }
+
+    return DSTAR_RADIO_BIT_LENGTH;
+}
+
 /* Init */
diff --git a/DSP_API/ThumbDV/gmsk_modem.h b/DSP_API/ThumbDV/gmsk_modem.h
index bdd05f0..665d569 100644
--- a/DSP_API/ThumbDV/gmsk_modem.h
+++ b/DSP_API/ThumbDV/gmsk_modem.h
@@ -46,4 +46,9 @@ typedef struct _gmsk_mod
     BOOL m_invert;
 } gmsk_mod, * GMSK_MOD;
 
+uint32 gmsk_encode(GMSK_MOD mod, BOOL bit, float * buffer, unsigned int length);
+enum DEMOD_STATE gmsk_decode(GMSK_DEMOD demod, float val);
+
+void gmskDemod_reset(GMSK_DEMOD demod );
+
 #endif /* THUMBDV_GMSK_MODEM_H_ */