// Original DMR filter #define NZEROS 60 float ngain = 7.423339364f; static float xv[NZEROS+1]; float xcoeffs[] = { -0.0083649323f, -0.0265444850f, -0.0428141462f, -0.0537571943f, -0.0564141052f, -0.0489161045f, -0.0310068662f, -0.0043393881f, +0.0275375106f, +0.0595423283f, +0.0857543325f, +0.1003565948f, +0.0986944931f, +0.0782804830f, +0.0395670487f, -0.0136691535f, -0.0744390415f, -0.1331834575f, -0.1788967208f, -0.2005995448f, -0.1889627181f, -0.1378439993f, -0.0454976231f, +0.0847488694f, +0.2444859269f, +0.4209222342f, +0.5982295474f, +0.7593684540f, +0.8881539892f, +0.9712773915f, +0.9999999166f, +0.9712773915f, +0.8881539892f, +0.7593684540f, +0.5982295474f, +0.4209222342f, +0.2444859269f, +0.0847488694f, -0.0454976231f, -0.1378439993f, -0.1889627181f, -0.2005995448f, -0.1788967208f, -0.1331834575f, -0.0744390415f, -0.0136691535f, +0.0395670487f, +0.0782804830f, +0.0986944931f, +0.1003565948f, +0.0857543325f, +0.0595423283f, +0.0275375106f, -0.0043393881f, -0.0310068662f, -0.0489161045f, -0.0564141052f, -0.0537571943f, -0.0428141462f, -0.0265444850f, -0.0083649323f, }; //reverted to original NXDN filters, do better with LICH/Data handling // NXDN48 filter - Original Version #define NXZEROS 134 float nxgain = 15.95930463f; static float nxv[NXZEROS+1]; float nxcoeffs[] = { +0.031462429f, +0.031747267f, +0.030401148f, +0.027362877f, +0.022653298f, +0.016379869f, +0.008737200f, +0.000003302f, -0.009468531f, -0.019262057f, -0.028914291f, -0.037935027f, -0.045828927f, -0.052119261f, -0.056372283f, -0.058221106f, -0.057387924f, -0.053703443f, -0.047122444f, -0.037734535f, -0.025769308f, -0.011595336f, +0.004287292f, +0.021260954f, +0.038610717f, +0.055550276f, +0.071252765f, +0.084885375f, +0.095646450f, +0.102803611f, +0.105731303f, +0.103946126f, +0.097138329f, +0.085197939f, +0.068234131f, +0.046586711f, +0.020828821f, -0.008239664f, -0.039608255f, -0.072081234f, -0.104311776f, -0.134843790f, -0.162160200f, -0.184736015f, -0.201094346f, -0.209863285f, -0.209831516f, -0.200000470f, -0.179630919f, -0.148282051f, -0.105841323f, -0.052543664f, +0.011020985f, +0.083912428f, +0.164857408f, +0.252278939f, +0.344336996f, +0.438979335f, +0.534000832f, +0.627109358f, +0.715995947f, +0.798406824f, +0.872214756f, +0.935487176f, +0.986548646f, +1.024035395f, +1.046939951f, +1.054644241f, +1.046939951f, +1.024035395f, +0.986548646f, +0.935487176f, +0.872214756f, +0.798406824f, +0.715995947f, +0.627109358f, +0.534000832f, +0.438979335f, +0.344336996f, +0.252278939f, +0.164857408f, +0.083912428f, +0.011020985f, -0.052543664f, -0.105841323f, -0.148282051f, -0.179630919f, -0.200000470f, -0.209831516f, -0.209863285f, -0.201094346f, -0.184736015f, -0.162160200f, -0.134843790f, -0.104311776f, -0.072081234f, -0.039608255f, -0.008239664f, +0.020828821f, +0.046586711f, +0.068234131f, +0.085197939f, +0.097138329f, +0.103946126f, +0.105731303f, +0.102803611f, +0.095646450f, +0.084885375f, +0.071252765f, +0.055550276f, +0.038610717f, +0.021260954f, +0.004287292f, -0.011595336f, -0.025769308f, -0.037734535f, -0.047122444f, -0.053703443f, -0.057387924f, -0.058221106f, -0.056372283f, -0.052119261f, -0.045828927f, -0.037935027f, -0.028914291f, -0.019262057f, -0.009468531f, +0.000003302f, +0.008737200f, +0.016379869f, +0.022653298f, +0.027362877f, +0.030401148f, +0.031747267f, +0.031462429f, }; // DMR filter F4EXB #define DMRNZEROS 60 // DMR filter F4EXB const float dmrgain = 6.82973073748f; // DMR filter F4EXB static float dxv[DMRNZEROS+1]; // DMR filter F4EXB - root raised cosine alpha=0.7 Ts = 6650 S/s Fc = 48kHz const float dmrcoeffs[] = {0.0301506278, 0.0269200615, 0.0159662432, -0.0013114705, -0.0216605133, -0.0404938748, -0.0528141756, -0.0543747957, -0.0428325003, -0.0186176083, 0.0147202645, 0.0508418571, 0.0816392577, 0.0988113688, 0.0957187780, 0.0691512084, 0.0206194642, -0.0431564563, -0.1107569268, -0.1675773224, -0.1981519842, -0.1889130786, -0.1308939560, -0.0218608492, 0.1325685970, 0.3190962499, 0.5182530574, 0.7070497652, 0.8623526878, 0.9644213921, 1.0000000000, 0.9644213921, 0.8623526878, 0.7070497652, 0.5182530574, 0.3190962499, 0.1325685970, -0.0218608492, -0.1308939560, -0.1889130786, -0.1981519842, -0.1675773224, -0.1107569268, -0.0431564563, 0.0206194642, 0.0691512084, 0.0957187780, 0.0988113688, 0.0816392577, 0.0508418571, 0.0147202645, -0.0186176083, -0.0428325003, -0.0543747957, -0.0528141756, -0.0404938748, -0.0216605133, -0.0013114705, 0.0159662432, 0.0269200615, 0.0301506278}; // dPMR filter, version of F4EXB static float dpmrxv[NXZEROS+1]; // dPMR filter, version of F4EXB #define DPMRNZEROS 134 // dPMR filter, version of F4EXB const float dpmrgain = 14.6083498224f; // dPMR filter - root raised cosine alpha=0.2 Ts = 3325 S/s Fc = 48 kHz - zero at boundaries appears to be slightly better const float dpmrcoeffs[] = {-0.0000983004, 0.0058388841, 0.0119748846, 0.0179185547, 0.0232592816, 0.0275919612, 0.0305433586, 0.0317982965, 0.0311240307, 0.0283911865, 0.0235897433, 0.0168387650, 0.0083888763, -0.0013831396, -0.0119878087, -0.0228442151, -0.0333082708, -0.0427067804, -0.0503756642, -0.0557003599, -0.0581561791, -0.0573462646, -0.0530347941, -0.0451732069, -0.0339174991, -0.0196350217, -0.0028997157, 0.0155246961, 0.0347134030, 0.0536202583, 0.0711271166, 0.0861006725, 0.0974542022, 0.1042112035, 0.1055676660, 0.1009496091, 0.0900625944, 0.0729301774, 0.0499186839, 0.0217462748, -0.0105250265, -0.0455148664, -0.0815673067, -0.1168095612, -0.1492246435, -0.1767350726, -0.1972941202, -0.2089805758, -0.2100926829, -0.1992367833, -0.1754063031, -0.1380470370, -0.0871052089, -0.0230554989, 0.0530929052, 0.1398131936, 0.2351006721, 0.3365341927, 0.4413570929, 0.5465745033, 0.6490630781, 0.7456885564, 0.8334261381, 0.9094784589, 0.9713859928, 1.0171250045, 1.0451886943, 1.0546479089, 1.0451886943, 1.0171250045, 0.9713859928, 0.9094784589, 0.8334261381, 0.7456885564, 0.6490630781, 0.5465745033, 0.4413570929, 0.3365341927, 0.2351006721, 0.1398131936, 0.0530929052, -0.0230554989, -0.0871052089, -0.1380470370, -0.1754063031, -0.1992367833, -0.2100926829, -0.2089805758, -0.1972941202, -0.1767350726, -0.1492246435, -0.1168095612, -0.0815673067, -0.0455148664, -0.0105250265, 0.0217462748, 0.0499186839, 0.0729301774, 0.0900625944, 0.1009496091, 0.1055676660, 0.1042112035, 0.0974542022, 0.0861006725, 0.0711271166, 0.0536202583, 0.0347134030, 0.0155246961, -0.0028997157, -0.0196350217, -0.0339174991, -0.0451732069, -0.0530347941, -0.0573462646, -0.0581561791, -0.0557003599, -0.0503756642, -0.0427067804, -0.0333082708, -0.0228442151, -0.0119878087, -0.0013831396, 0.0083888763, 0.0168387650, 0.0235897433, 0.0283911865, 0.0311240307, 0.0317982965, 0.0305433586, 0.0275919612, 0.0232592816, 0.0179185547, 0.0119748846, 0.0058388841, -0.0000983004}; short dsd_input_filter(short sample, int mode); short dmr_filter(short sample) { return dsd_input_filter(sample, 3); } short nxdn_filter(short sample) { return dsd_input_filter(sample, 2); } short dpmr_filter(short sample) { return dsd_input_filter(sample, 4); } short dsd_input_filter(short sample, int mode) { float sum; int i; float gain; int zeros; float *v, *coeffs; switch(mode) { case 1: gain = ngain; v = xv; coeffs = xcoeffs; zeros = NZEROS; break; case 2: gain = nxgain; v = nxv; coeffs = (float *)nxcoeffs; zeros = NXZEROS; break; case 3: gain = dmrgain; v = dxv; coeffs = (float *)dmrcoeffs; zeros = DMRNZEROS; break; case 4: gain = dpmrgain; v = dpmrxv; coeffs = (float *)dpmrcoeffs; zeros = DPMRNZEROS; break; default: return sample; } for (i = 0; i < zeros; i++) v[i] = v[i+1]; v[zeros] = (float)sample; // unfiltered sample in sum = 0.0f; for (i = 0; i <= zeros; i++) sum += (coeffs[i] * v[i]); return (short)(sum / gain); // filtered sample out }