Merge pull request #313 from arancormonk/perf/rtl-sdr-fm-resampler-simd-rotate90

rtl_sdr_fm: fix FLL feedback and rotate_90 tail; aligned/SIMD resampler; safer defaults and logs

.gitignore

@@ -9,4 +9,5 @@ examples
 *.ans
 *.patch
 *.zip
-result
+result
+.cache

include/dsd.h

@@ -371,7 +371,7 @@ typedef struct
   int rtl_udp_port;
   int rtl_bandwidth;
   int rtl_started;
-  long int rtl_rms;
+  long int rtl_pwr;
   int monitor_input_audio;
   int analog_only;
   int pulse_raw_rate_in;
@@ -960,7 +960,7 @@ typedef struct
   uint8_t m17_can; //can value that was decoded from signal
   int m17_can_en; //can value supplied to the encoding side
   int m17_rate;  //sampling rate for audio input
-  int m17_vox;  //vox enabled via RMS value
+  int m17_vox;  //vox enabled via PWR value
 
   char m17_dst_csd[20];
   char m17_src_csd[20];
@@ -1580,6 +1580,7 @@ void init_rrc_filter_memory();
 
 //misc audio filtering for analog
 long int raw_rms(short *samples, int len, int step);
+long int raw_pwr(short *samples, int len, int step);
 void init_audio_filters(dsd_state * state);
 void lpf(dsd_state * state, short * input, int len);
 void hpf(dsd_state * state, short * input, int len);
@@ -1660,7 +1661,7 @@ void cleanup_rtlsdr_stream();
 int get_rtlsdr_sample(int16_t *sample, dsd_opts * opts, dsd_state * state);
 void rtlsdr_sighandler();
 void rtl_dev_tune(dsd_opts * opts, long int frequency);
-long int rtl_return_rms();
+long int rtl_return_pwr();
 void rtl_clean_queue();
 #endif
 

src/dsd_frame_sync.c

@@ -419,8 +419,8 @@ getFrameSync (dsd_opts * opts, dsd_state * state)
             }
 
 
-          //if using an rtl input method, do not look for sync patterns if the rms value is lower than our 'soft squelch' level
-          if (opts->audio_in_type == 3 && opts->rtl_rms < opts->rtl_squelch_level)
+          //if using an rtl input method, do not look for sync patterns if the pwr value is lower than our 'soft squelch' level
+          if (opts->audio_in_type == 3 && opts->rtl_pwr < opts->rtl_squelch_level)
           {
             if (opts->frame_nxdn48 == 1 || opts->frame_nxdn96 == 1 || opts->frame_dpmr == 1 || opts->frame_m17 == 1)
             {

src/dsd_main.c

@@ -689,14 +689,14 @@
    //all RTL user options -- enabled AGC by default due to weak signal related issues
    opts->rtl_dev_index = 0;        //choose which device we want by index number
    opts->rtl_gain_value = 0;     //mid value, 0 - AGC - 0 to 49 acceptable values
-   opts->rtl_squelch_level = 100; //100 by default, but only affects NXDN and dPMR during framesync test, compared to RMS value
+   opts->rtl_squelch_level = 10000; //default scaled for rtl_pwr (RMS^2 proxy); ~100 RMS equivalent
    opts->rtl_volume_multiplier = 2; //sample multiplier; This multiplies the sample value to produce a higher 'inlvl' for the demodulator
    opts->rtl_udp_port = 0; //set UDP port for RTL remote -- 0 by default, will be making this optional for some external/legacy use cases (edacs-fm, etc)
    opts->rtl_bandwidth = 12; //default is 12, reverted back to normal on this (no inherent benefit)
    opts->rtlsdr_ppm_error = 0; //initialize ppm with 0 value;
    opts->rtlsdr_center_freq = 850000000; //set to an initial value (if user is using a channel map, then they won't need to specify anything other than -i rtl if desired)
    opts->rtl_started = 0;
-   opts->rtl_rms = 0; //root means square power level on rtl input signal
+   opts->rtl_pwr = 0; // mean power approximation level on rtl input signal
    //end RTL user options
    opts->pulse_raw_rate_in   = 48000;
    opts->pulse_raw_rate_out  = 48000;//
@@ -1461,7 +1461,7 @@
    printf ("  gain <num>    RTL-SDR Device Gain (0-49)(default = 0; Hardware AGC recommended)\n");
    printf ("  ppm  <num>    RTL-SDR PPM Error (default = 0)\n");
    printf ("  bw   <num>    RTL-SDR Bandwidth kHz (default = 12)(4, 6, 8, 12, 16, 24)  \n");
-   printf ("  sq   <num>    RTL-SDR Squelch Level vs RMS Value (Optional)\n");
+   printf ("  sq   <num>    RTL-SDR Squelch Level vs PWR Value (Optional)\n");
    // printf ("  udp  <num>    RTL-SDR Legacy UDP Remote Port (Optional -- External Use Only)\n"); //NOTE: This is still available as an option in the ncurses menu
    printf ("  vol  <num>    RTL-SDR Sample 'Volume' Multiplier (default = 2)(1,2,3)\n");
    printf (" Example: dsd-fme -fs -i rtl -C cap_plus_channel.csv -T\n");
@@ -1644,8 +1644,8 @@
      open_rtlsdr_stream(opts);
      opts->rtl_started = 1; //set here so ncurses terminal doesn't attempt to open it again
      // #ifdef __arm__
-     // fprintf (stderr, "WARNING: RMS Function is Disabled on ARM Devices (Raspberry Pi) due to High CPU use. \n");
-     // fprintf (stderr, "RMS/Squelch Functionality for NXDN, dPMR, EDACS Analog, M17 and Raw Audio Monitor are unavailable and these modes will not function properly. \n");
+     // fprintf (stderr, "WARNING: PWR Function is Disabled on ARM Devices (Raspberry Pi) due to High CPU use. \n");
+     // fprintf (stderr, "PWR/Squelch Functionality for NXDN, dPMR, EDACS Analog, M17 and Raw Audio Monitor are unavailable and these modes will not function properly. \n");
      // if (opts->monitor_input_audio == 1) opts->monitor_input_audio = 0;
      // opts->rtl_squelch_level = 0;
      // #endif

src/dsd_misc.c

@@ -591,4 +591,28 @@ long int raw_rms(int16_t *samples, int len, int step) //use samplespersymbol as
   rms = (long int)sqrt((p-err) / len);
   if (rms < 0) rms = 150;
   return rms;
+}
+
+/*
+ * Mean power (RMS^2 proxy) without sqrt, modeled after mean_power() in rtl_sdr_fm.cpp.
+ * Computes a DC-corrected average of squares to avoid costly sqrt operations.
+ */
+long int raw_pwr(int16_t *samples, int len, int step)
+{
+  int64_t p = 0;
+  int64_t t = 0;
+  for (int i = 0; i < len; i += step) {
+    int64_t s = (int64_t)samples[i];
+    t += s;
+    p += s * s;
+  }
+  /* DC-corrected energy ≈ p - (t^2)/len with rounded division */
+  int64_t dc_corr = 0;
+  if (len > 0) {
+    int64_t tt = t * t;
+    dc_corr = (tt + (len / 2)) / len;
+  }
+  int64_t energy = p - dc_corr;
+  if (energy < 0) energy = 0;
+  return (long int)(energy / (len > 0 ? len : 1));
 }

src/dsd_ncurses_menu.c

@@ -417,7 +417,7 @@ void ncursesMenu (dsd_opts * opts, dsd_state * state)
 
           entry_win = newwin(8, WIDTH+22, starty+10, startx+10);
           box (entry_win, 0, 0);
-          mvwprintw(entry_win, 2, 2, " RTL RMS Squelch Level (NXDN/dPMR/Analog/Raw only): ");
+          mvwprintw(entry_win, 2, 2, " RTL Power Squelch Level (NXDN/dPMR/Analog/Raw only): ");
           mvwprintw(entry_win, 3, 3, " ");
           echo();
           refresh();
@@ -463,7 +463,7 @@ void ncursesMenu (dsd_opts * opts, dsd_state * state)
           mvwprintw(entry_win, 8, 2, " RTL Volume Multiplier: %d", opts->rtl_volume_multiplier);
           mvwprintw(entry_win, 9, 2, " RTL Device UDP Port: %d", opts->rtl_udp_port);
           mvwprintw(entry_win, 10, 2, " RTL Device PPM: %d", opts->rtlsdr_ppm_error);
-          mvwprintw(entry_win, 11, 2, " RTL RMS Squelch: %d", opts->rtl_squelch_level);
+          mvwprintw(entry_win, 11, 2, " RTL PWR Squelch: %d", opts->rtl_squelch_level);
           mvwprintw(entry_win, 13, 2, " Are You Sure?");
           mvwprintw(entry_win, 14, 2, " 1 = Yes, 2 = No ");
           mvwprintw(entry_win, 15, 3, " ");

src/dsd_ncurses_printer.c

@@ -255,7 +255,7 @@ ncursesPrinter (dsd_opts * opts, dsd_state * state)
     printw (" V: %iX;", opts->rtl_volume_multiplier);
     printw (" PPM: %i;", opts->rtlsdr_ppm_error); //Adjust manually now with { and }
     printw (" SQ: %i;", opts->rtl_squelch_level);
-    printw (" RMS: %04li;", opts->rtl_rms);
+    printw (" PWR: %04li;", opts->rtl_pwr);
     printw (" BW: %i;", opts->rtl_bandwidth);
     printw (" FRQ: %i;", opts->rtlsdr_center_freq);
     if (opts->rtl_udp_port != 0) printw ("\n| External RTL Tuning on UDP Port: %i", opts->rtl_udp_port);
@@ -282,7 +282,7 @@ ncursesPrinter (dsd_opts * opts, dsd_state * state)
     printw ("| Pulse Analog Output: %i kHz; %i Ch; G: %02.0f%% (/|*) ", opts->pulse_raw_rate_out/1000, opts->pulse_raw_out_channels, opts->audio_gainA);
     if (opts->audio_gainA == 0.0f) printw ("Auto   ");
     else printw ("Manual ");
-    if (opts->audio_in_type != 3) printw ("RMS: %04ld; ", opts->rtl_rms);
+    if (opts->audio_in_type != 3) printw ("PWR: %04ld; ", opts->rtl_pwr);
     if (opts->use_lpf == 1) printw ("F: |LP|"); else printw ("F: |  |");
     if (opts->use_hpf == 1) printw ("HP|");     else printw ("  |");
     if (opts->use_pbf == 1) printw ("PB|");     else printw ("  |");
@@ -302,7 +302,7 @@ ncursesPrinter (dsd_opts * opts, dsd_state * state)
 
     if ( (opts->audio_out_type == 5 && opts->pulse_digi_rate_out == 48000 && opts->pulse_digi_out_channels == 1) &&  (opts->frame_provoice == 1 || opts->monitor_input_audio == 1) )
     {
-      printw ("\n| Analog Monitor RMS: %04ld; G: %02.0f%% (/|*) ", opts->rtl_rms, opts->audio_gainA);
+      printw ("\n| Analog Monitor PWR: %04ld; G: %02.0f%% (/|*) ", opts->rtl_pwr, opts->audio_gainA);
       if (opts->audio_gainA == 0.0f) printw ("Auto   ");
       else printw ("Manual ");
       if (opts->use_lpf == 1) printw ("F: |LP|"); else printw ("F: |  |");
@@ -321,14 +321,14 @@ ncursesPrinter (dsd_opts * opts, dsd_state * state)
     if (opts->use_hpf_d == 1)  printw (" HPF");
     if (opts->call_alert == 1) printw (" *CA!"); //Call Alert
     if ( (opts->audio_out_type == 5 && opts->pulse_digi_rate_out == 48000 && opts->pulse_digi_out_channels == 1) &&  (opts->frame_provoice == 1 || opts->monitor_input_audio == 1) )
-      printw (" - Monitor RMS: %04ld ", opts->rtl_rms);
+      printw (" - Monitor PWR: %04ld ", opts->rtl_pwr);
     printw (" \n");
     if (opts->udp_sockfdA != 0) //Analog Output on udp port +2
     {
       printw ("| UDP Analog Output: %s:%d; 48 kHz 1 Ch; G: %02.0f%% (/|*) ", opts->udp_hostname, opts->udp_portno+2, opts->audio_gainA);
       if (opts->audio_gainA == 0.0f) printw ("A ");
       else printw ("M ");
-      if (opts->audio_in_type != 3) printw ("RMS: %04ld; ", opts->rtl_rms);
+      if (opts->audio_in_type != 3) printw ("PWR: %04ld; ", opts->rtl_pwr);
       if (opts->use_lpf == 1) printw ("F: |LP|"); else printw ("F: |  |");
       if (opts->use_hpf == 1) printw ("HP|");     else printw ("  |");
       if (opts->use_pbf == 1) printw ("PB|");     else printw ("  |");
@@ -347,7 +347,7 @@ ncursesPrinter (dsd_opts * opts, dsd_state * state)
     if (opts->use_lpf == 1) printw ("F: |LP|"); else printw ("F: |  |");
     if (opts->use_hpf == 1) printw ("HP|");     else printw ("  |");
     if (opts->use_pbf == 1) printw ("PB|");     else printw ("  |");
-    if (opts->audio_in_type != 3 && state->m17_vox == 1) printw ( " SQL: %04ld : %04d;", opts->rtl_rms, opts->rtl_squelch_level);
+    if (opts->audio_in_type != 3 && state->m17_vox == 1) printw ( " SQL: %04ld : %04d;", opts->rtl_pwr, opts->rtl_squelch_level);
     printw ("\n");
 
   }

src/dsd_symbol.c

@@ -132,7 +132,7 @@ getSymbol (dsd_opts * opts, dsd_state * state, int have_sync)
         if (get_rtlsdr_sample(&sample, opts, state) < 0)
           cleanupAndExit(opts, state);
         //update root means square power level
-        opts->rtl_rms = rtl_return_rms();
+        opts->rtl_pwr = rtl_return_pwr();
         sample *= opts->rtl_volume_multiplier;
 
 #endif
@@ -268,9 +268,9 @@ getSymbol (dsd_opts * opts, dsd_state * state, int have_sync)
 
         if (state->analog_sample_counter == 960)
         {
-          //get an rms value if not using the rtl built in version
+          //get an pwr value if not using the rtl built in version
           if (opts->audio_in_type != 3  && opts->monitor_input_audio == 1)
-            opts->rtl_rms = raw_rms(state->analog_out, 960, 1);
+            opts->rtl_pwr = raw_pwr(state->analog_out, 960, 1);
 
           //raw wav file saving -- only write when not NXDN, dPMR, or M17 due to noise that can cause tons of false positives when no sync
           if (opts->wav_out_raw != NULL && opts->frame_nxdn48 == 0 && opts->frame_nxdn96 == 0 && opts->frame_dpmr == 0 && opts->frame_m17 == 0)
@@ -299,13 +299,13 @@ getSymbol (dsd_opts * opts, dsd_state * state, int have_sync)
           else
             agsm(opts, state, state->analog_out, 960);
 
-          //Running RMS after filtering does remove the analog spike from the RMS value
+          //Running PWR after filtering does remove the analog spike from the PWR value
           //but noise floor noise will still produce higher values
           // if (opts->audio_in_type != 3  && opts->monitor_input_audio == 1)
-          //   opts->rtl_rms = raw_rms(state->analog_out, 960, 1);
+          //   opts->rtl_pwr = raw_pwr(state->analog_out, 960, 1);
 
-          //seems to be working now, but RMS values are lower on actual analog signal than on no signal but noise
-          if ( (opts->rtl_rms > opts->rtl_squelch_level) && opts->monitor_input_audio == 1 && state->carrier == 0 ) //added carrier check here in lieu of disabling it above
+          //seems to be working now, but PWR values are lower on actual analog signal than on no signal but noise
+          if ( (opts->rtl_pwr > opts->rtl_squelch_level) && opts->monitor_input_audio == 1 && state->carrier == 0 ) //added carrier check here in lieu of disabling it above
           {
             if (opts->audio_out_type == 0)
               pa_simple_write(opts->pulse_raw_dev_out, state->analog_out, 960*2, NULL);

src/edacs-fme.c

@@ -179,7 +179,7 @@ unsigned long long int edacsVoteFr(unsigned long long int fr_1_4, unsigned long
 void edacs_analog(dsd_opts * opts, dsd_state * state, int afs, unsigned char lcn)
 {
   int i, result;
-  int count = 5; //RMS has a 5 count (5 * 180ms) now before cutting off;
+  int count = 5; //PWR has a 5 count (5 * 180ms) now before cutting off;
   short analog1[960];
   short analog2[960];
   short analog3[960];
@@ -202,7 +202,7 @@ void edacs_analog(dsd_opts * opts, dsd_state * state, int afs, unsigned char lcn
   memset (d2, 0, sizeof(d2));
   memset (d3, 0, sizeof(d3));
 
-  long int rms = opts->rtl_squelch_level + 1; //one more for the initial loop phase
+  long int pwr = opts->rtl_squelch_level + 1; //one more for the initial loop phase
   long int sql = opts->rtl_squelch_level;
 
   fprintf (stderr, "\n");
@@ -229,8 +229,8 @@ void edacs_analog(dsd_opts * opts, dsd_state * state, int afs, unsigned char lcn
         pa_simple_read(opts->pulse_digi_dev_in, &sample, 2, NULL );
         analog3[i] = sample;
       }
-      //this rms will only work properly (for now) with squelch enabled in SDR++ or other
-      rms = raw_rms(analog3, 960, 1);
+      //this pwr will only work properly (for now) with squelch enabled in SDR++ or other
+      pwr = raw_pwr(analog3, 960, 1);
     }
 
     //NOTE: The core dumps observed previously were due to SDR++ Remote Server connection dropping due to Internet/Other issues
@@ -287,8 +287,8 @@ void edacs_analog(dsd_opts * opts, dsd_state * state, int afs, unsigned char lcn
         analog3[i] = sample;
       }
 
-      //this rms will only work properly (for now) with squelch enabled in SDR++
-      rms = raw_rms(analog3, 960, 1);
+      //this pwr will only work properly (for now) with squelch enabled in SDR++
+      pwr = raw_pwr(analog3, 960, 1);
     }
 
     //RTL Input
@@ -315,8 +315,8 @@ void edacs_analog(dsd_opts * opts, dsd_state * state, int afs, unsigned char lcn
         sample *= opts->rtl_volume_multiplier;
         analog3[i] = sample;
       }
-      //the rtl rms value works properly without needing a 'hard' squelch value
-      rms = rtl_return_rms();
+      //the rtl pwr value works properly without needing a 'hard' squelch value
+      pwr = rtl_return_pwr();
     }
     #endif
 
@@ -387,12 +387,12 @@ void edacs_analog(dsd_opts * opts, dsd_state * state, int afs, unsigned char lcn
       agsm (opts, state, analog3, 960);
     }
 
-    //NOTE: Ideally, we would run raw_rms for TCP/VS here, but the analog spike on EDACS (STM)
+    //NOTE: Ideally, we would run raw_pwr for TCP/VS here, but the analog spike on EDACS (STM)
     //system gets filtered out, and when they hold the radio open and don't talk,
     //it counts against the squelch hit as no audio, so we will just have to use
     //the squelch checkbox in SDR++ and similar when using those input methods
     // if (opts->audio_in_type != 3)
-    //   rms = raw_rms(analog3, 960, 1);
+    //   pwr = raw_pwr(analog3, 960, 1);
 
     //reconfigured to use seperate audio out stream that is always 48k short
     if (opts->audio_out_type == 0 && opts->slot1_on == 1)
@@ -425,18 +425,18 @@ void edacs_analog(dsd_opts * opts, dsd_state * state, int afs, unsigned char lcn
       write (opts->audio_out_fd, analog3, 960*2);
     }
 
-    opts->rtl_rms = rms;
+    opts->rtl_pwr = pwr;
 
 
     printFrameSync (opts, state, " EDACS", 0, "A");
 
-    if (rms < sql) count--;
+    if (pwr < sql) count--;
     else count = 5;
 
-    if (rms > sql) fprintf(stderr, "%s", KGRN);
+    if (pwr > sql) fprintf(stderr, "%s", KGRN);
     else fprintf(stderr, "%s", KRED);
 
-    fprintf (stderr, " Analog RMS: %04ld SQL: %ld", rms, sql);
+    fprintf (stderr, " Analog PWR: %04ld SQL: %ld", pwr, sql);
     if (state->ea_mode == 0)
     {
       int a = (afs >> state->edacs_a_shift) & state->edacs_a_mask;
@@ -1488,7 +1488,7 @@ void edacs(dsd_opts * opts, dsd_state * state)
 
         //NOTE: Restructured below so that analog and digital are handled the same, just that when
         //its analog, it will now start edacs_analog which will while loop analog samples until
-        //signal level drops (RMS, or a dotting sequence is detected)
+        //signal level drops (PWR, or a dotting sequence is detected)
 
         //this is working now with the new import setup
         if (opts->trunk_tune_group_calls == 1 && opts->p25_trunk == 1 && (strcmp(mode, "DE") != 0) && (strcmp(mode, "B") != 0) ) //DE is digital encrypted, B is block
@@ -1743,7 +1743,7 @@ void edacs(dsd_opts * opts, dsd_state * state)
 
           //NOTE: Restructured below so that analog and digital are handled the same, just that when
           //its analog, it will now start edacs_analog which will while loop analog samples until
-          //signal level drops (RMS, or a dotting sequence is detected)
+          //signal level drops (PWR, or a dotting sequence is detected)
 
           //this is working now with the new import setup
           if (((is_individual == 0 && opts->trunk_tune_group_calls == 1) || (is_individual == 1 && opts->trunk_tune_private_calls == 1)) &&
@@ -1857,7 +1857,7 @@ void edacs(dsd_opts * opts, dsd_state * state)
 
           //NOTE: Restructured below so that analog and digital are handled the same, just that when
           //its analog, it will now start edacs_analog which will while loop analog samples until
-          //signal level drops (RMS, or a dotting sequence is detected)
+          //signal level drops (PWR, or a dotting sequence is detected)
 
           //this is working now with the new import setup
           if ((opts->trunk_tune_private_calls == 1) && opts->p25_trunk == 1 && (strcmp(mode, "DE") != 0) && (strcmp(mode, "B") != 0) ) //DE is digital encrypted, B is block
@@ -2153,7 +2153,7 @@ void edacs(dsd_opts * opts, dsd_state * state)
 
             //NOTE: Restructured below so that analog and digital are handled the same, just that when
             //its analog, it will now start edacs_analog which will while loop analog samples until
-            //signal level drops (RMS, or a dotting sequence is detected)
+            //signal level drops (PWR, or a dotting sequence is detected)
 
             //this is working now with the new import setup
             if ((opts->trunk_tune_group_calls == 1) && opts->p25_trunk == 1 && (strcmp(mode, "DE") != 0) && (strcmp(mode, "B") != 0) ) //DE is digital encrypted, B is block

src/m17.c

@@ -1962,13 +1962,13 @@ void encodeM17STR(dsd_opts * opts, dsd_state * state)
           voice2[i] = sample;
         }
       }
-      opts->rtl_rms = rtl_return_rms();
+      opts->rtl_pwr = rtl_return_pwr();
       #endif
     }
 
-    //read in RMS value for vox function; NOTE: will not work correctly SOCAT STDIO TCP due to blocking when no samples to read
+    //read in power value for vox function; use mean power (RMS^2 proxy) for consistency with rtl_pwr
     if (opts->audio_in_type != 3)
-      opts->rtl_rms = raw_rms(voice1, nsam, 1) / 2; //dividing by two so mic isn't so sensitive on vox
+      opts->rtl_pwr = raw_pwr(voice1, nsam, 1);
 
     //low pass filter
     if (opts->use_lpf == 1)
@@ -2010,11 +2010,11 @@ void encodeM17STR(dsd_opts * opts, dsd_state * state)
         agsm (opts, state, voice2, 160);
     }
 
-    //NOTE: Similar to EDACS analog, if calculating raw rms here after filtering,
+    //NOTE: Similar to EDACS analog, if calculating raw pwr here after filtering,
     //anytime the walkie-talkie is held open but no voice, the center spike is removed,
     //and counts against the squelch hits making vox mode inconsistent
     // if (opts->audio_in_type != 3)
-    //   opts->rtl_rms = raw_rms(voice1, 160, 1);
+    //   opts->rtl_pwr = raw_pwr(voice1, 160, 1);
 
     //convert out audio input into CODEC2 (3200bps) 8 byte data stream
     uint8_t vc1_bytes[8]; memset (vc1_bytes, 0, sizeof(vc1_bytes));
@@ -2080,8 +2080,8 @@ void encodeM17STR(dsd_opts * opts, dsd_state * state)
       m17_v1[i+16+64] = v2_bits[i];
     }
 
-    //tally consecutive squelch hits based on RMS value, or reset
-    if (opts->rtl_rms > opts->rtl_squelch_level) sql_hit = 0;
+    //tally consecutive squelch hits based on PWR value, or reset
+    if (opts->rtl_pwr > opts->rtl_squelch_level) sql_hit = 0;
     else sql_hit++; //may eventually roll over to 0 again
 
     //if vox enabled, toggle tx/eot with sql_hit comparison
@@ -2215,10 +2215,10 @@ void encodeM17STR(dsd_opts * opts, dsd_state * state)
       if (use_ip == 1 && lich_cnt != 5)
         fprintf (stderr, " UDP: %s:%d", opts->m17_hostname, udpport);
 
-      //debug RMS Value
+      //debug power value
       if (state->m17_vox == 1)
       {
-        fprintf (stderr, " RMS: %04ld", opts->rtl_rms);
+        fprintf (stderr, " PWR: %04ld", opts->rtl_pwr);
         fprintf (stderr, " SQL HIT: %d;", sql_hit);
       }
 
@@ -2463,10 +2463,10 @@ void encodeM17STR(dsd_opts * opts, dsd_state * state)
         if (use_ip == 1 && lich_cnt != 5)
           fprintf (stderr, " UDP: %s:%d", opts->m17_hostname, udpport);
 
-        //debug RMS Value
+        //debug power value
         if (state->m17_vox == 1)
         {
-          fprintf (stderr, " RMS: %04ld", opts->rtl_rms);
+          fprintf (stderr, " PWR: %04ld", opts->rtl_pwr);
           fprintf (stderr, " SQL HIT: %d;", sql_hit);
         }