diff --git a/acars.c b/acars.c
index 4b0528d..e25c672 100644
--- a/acars.c
+++ b/acars.c
@@ -213,6 +213,7 @@ static void *blk_thread(void *arg)
 				{ .type = STATSD_UCOUNTER, .name = "decoder.msg.good", .value.u = 1 },
 				{ .type = STATSD_LGAUGE, .name = "decoder.msg.errs", .value.l = blk->err },
 				{ .type = STATSD_FGAUGE, .name = "decoder.msg.lvl", .value.f = blk->lvl },
+				{ .type = STATSD_FGAUGE, .name = "decoder.msg.nf", .value.f = blk->nf },
 				{ .type = STATSD_LGAUGE, .name = "decoder.msg.len", .value.l = blk->txtlen },
 			};
 			// use the frequency if available, else the channel number
@@ -251,18 +252,22 @@ int initAcars(channel_t *ch)
 
 void decodeAcars(channel_t *ch)
 {
+	const float mag = ch->MskMag;
 	uint8_t r = ch->outbits;
 	//vprerr("#%d r: %x, count: %d, st: %d\n", ch->chn+1, r, ch->count, ch->Acarsstate);
 
 	ch->nbits = 8;	// by default we'll read another byte next
 
+	/* update power level exp moving average. Average over last 16 bytes */
+	ch->MskPwr = ch->MskPwr - (1.0F/16.0F * (ch->MskPwr - mag * mag));
+
 	switch (ch->Acarsstate) {
 	case PREKEY:
 		if (ch->count >= 16 && 0xFF != r) {	// we have our first non-0xFF byte after a sequence
 			uint8_t q = ~r;	// avoid type promotion in calling ffs(~r)
 			int l = ffs(q);		// find the first (LSb) 0 in r
 
-			vprerr("#%d synced, count: %d, r: %x, fz: %d, lvl: %5.1f\n", ch->chn+1, ch->count, r, l, 10 * log10(ch->MskLvl));
+			vprerr("#%d synced, count: %d, r: %x, fz: %d, lvl: %5.1f\n", ch->chn+1, ch->count, r, l, 10 * log10(ch->MskPwr));
 			ch->count = 0;
 			ch->Acarsstate = SYNC;
 
@@ -299,6 +304,8 @@ void decodeAcars(channel_t *ch)
 				ch->count++;
 				break;
 			default:
+				/* outside of msgs, update noise floor moving average: long term (10^3 'bytes') magnitude exp moving average */
+				ch->MskNF = ch->MskNF - (1e-3F * (ch->MskNF - mag));
 				ch->count = 0;
 				break;
 			}
@@ -347,7 +354,8 @@ void decodeAcars(channel_t *ch)
 			}
 			gettimeofday(&(ch->blk->tv), NULL);
 			ch->Acarsstate = TXT;
-			ch->blk->lvl = 10 * log10(ch->MskLvl);
+			ch->blk->lvl = 10 * log10(ch->MskPwr);
+			ch->blk->nf = 20 * log10(ch->MskNF);
 			ch->blk->chn = ch->chn;
 			ch->blk->txtlen = 0;
 			ch->blk->err = 0;
diff --git a/acarsdec.h b/acarsdec.h
index e3ec7ff..7521b64 100644
--- a/acarsdec.h
+++ b/acarsdec.h
@@ -54,7 +54,7 @@
 typedef struct mskblk_s {
 	struct mskblk_s *prev;
 	struct timeval tv;
-	float lvl;
+	float lvl, nf;
 	uint8_t chn;	// there will never be 255 channels
 	uint8_t txtlen;
 	uint8_t err;
@@ -88,7 +88,7 @@ typedef struct {
 	char be;
 	char msn[4];		// only for libacars - null-terminated copy of msg.no[0-3]
 	int err;
-	float lvl;
+	float lvl, nf;
 #ifdef HAVE_LIBACARS
 	la_reasm_status reasm_status;
 	la_proto_node *decoded_tree;
@@ -104,7 +104,9 @@ typedef struct {
 	float complex *inb;
 	double MskPhi;
 	double MskDf;
-	float MskLvl;
+	float MskMag;				// signal magnitude moving average
+	float MskPwr;				// signal power moving average (average of magnitude squared)
+	float MskNF;				// noise floor moving average (average of magnitude outside of msg blocks)
 	float MskClk;
 	unsigned int MskS, idx;
 
diff --git a/msk.c b/msk.c
index 16b6143..7a2e4cd 100644
--- a/msk.c
+++ b/msk.c
@@ -54,12 +54,10 @@ int initMsk(channel_t *ch)
 static inline void putbit(float v, channel_t *ch)
 {
 	ch->outbits >>= 1;
-	if (v > 0) {
+	if (v > 0)
 		ch->outbits |= 0x80;
-	}
 
-	ch->nbits--;
-	if (ch->nbits <= 0)
+	if (--ch->nbits == 0)
 		decodeAcars(ch);
 }
 
@@ -106,12 +104,11 @@ void demodMSK(channel_t *ch, int len)
 				v += h[o] * ch->inb[(j + idx) % FLEN];
 
 			/* normalize */
-			lvl = cabsf(v);
-			v /= lvl + 1e-8;
+			lvl = cabsf(v) + 1e-8F;
+			v /= lvl;
 
-			/* update level exp moving average. Average over last 16*8 bits */
-			lvl = lvl * lvl;
-			ch->MskLvl = ch->MskLvl - (1.0F/128.0F * (ch->MskLvl - lvl));
+			/* update magnitude exp moving average. Average over last 8 bits */
+			ch->MskMag = ch->MskMag - (1.0F/8.0F * (ch->MskMag - lvl));
 
 			if (ch->MskS & 1) {
 				vo = cimagf(v);
diff --git a/output.c b/output.c
index 1f1433f..78ffa26 100644
--- a/output.c
+++ b/output.c
@@ -391,10 +391,10 @@ static int fmt_msg(acarsmsg_t *msg, int chn, struct timeval tv, char *buf, size_
 	int len = 0;
 
 	if (R.inmode >= IN_RTL)
-		len += snprintf(buf + len, bufsz - len, "[#%1d (F:%3.3f L:%+5.1f E:%1d) ", chn + 1,
-			R.channels[chn].Fr / 1000000.0, msg->lvl, msg->err);
+		len += snprintf(buf + len, bufsz - len, "[#%1d (F:%3.3f L:%+5.1f/%.1f E:%1d) ", chn + 1,
+			R.channels[chn].Fr / 1000000.0, msg->lvl, msg->nf, msg->err);
 	else
-		len += snprintf(buf + len, bufsz - len, "[#%1d (L:%+5.1f E:%1d) ", chn + 1, msg->lvl, msg->err);
+		len += snprintf(buf + len, bufsz - len, "[#%1d (L:%+5.1f/%.1f E:%1d) ", chn + 1, msg->lvl, msg->nf, msg->err);
 
 	if (R.inmode != IN_SNDFILE)
 		len += fmt_date(tv, buf + len, bufsz - len);
@@ -472,7 +472,7 @@ static int fmt_oneline(acarsmsg_t *msg, int chn, struct timeval tv, char *buf, s
 		if (*pstr == '\n' || *pstr == '\r')
 			*pstr = ' ';
 
-	len = snprintf(buf, bufsz, "#%1d (L:%+5.1f E:%1d) ", chn + 1, msg->lvl, msg->err);
+	len = snprintf(buf, bufsz, "#%1d (L:%+5.1f/%.1f E:%1d) ", chn + 1, msg->lvl, msg->nf, msg->err);
 
 	if (R.inmode != IN_SNDFILE)
 		len += fmt_date(tv, buf + len, bufsz - len);
@@ -575,6 +575,8 @@ static int fmt_json(acarsmsg_t *msg, int chn, struct timeval tv, char *buf, size
 	cJSON_AddRawToObject(json_obj, "freq", convert_tmp);
 	snprintf(convert_tmp, sizeof(convert_tmp), "%2.1f", msg->lvl);
 	cJSON_AddRawToObject(json_obj, "level", convert_tmp);
+	snprintf(convert_tmp, sizeof(convert_tmp), "%.1f", msg->nf);
+	cJSON_AddRawToObject(json_obj, "noise", convert_tmp);
 	cJSON_AddNumberToObject(json_obj, "error", msg->err);
 	snprintf(convert_tmp, sizeof(convert_tmp), "%c", msg->mode);
 	cJSON_AddStringToObject(json_obj, "mode", convert_tmp);
@@ -727,6 +729,7 @@ void outputmsg(const msgblk_t *blk)
 	/* fill msg struct */
 	memset(&msg, 0, sizeof(msg));
 	msg.lvl = blk->lvl;
+	msg.nf = blk->nf;
 	msg.err = blk->err;
 
 	msg.mode = blk->txt.d.mode;