add autogain

README.md

@@ -30,9 +30,10 @@ version: '3.8'
 
 services:
   tar1090:
-    image: ghcr.io/sdr-enthusiasts/docker-adsb-all-in-one:latest
+    image: ghcr.io/sdr-enthusiasts/docker-adsb-ultrafeeder:latest
     tty: true
-    container_name: adsb-all-in-one
+    container_name: ultrafeeder
+    hostname: ultrafeeder
     restart: always
     environment:
       - TZ=Australia/Perth
@@ -162,6 +163,34 @@ If you want to connect your SDR to the container, here's how to do that:
 | `READSB_GAIN` | Set gain (in dB). Use `autogain` to have the container determine an appropriate gain, more on this below. | `--gain=<db>` | Max gain |
 | `READSB_RTLSDR_PPM` | Set oscillator frequency correction in PPM. See [Estimating PPM](https://github.com/sdr-enthusiasts/docker-readsb-protobuf/README.MD#estimating-ppm)  | `--ppm=<correction>` | Unset |
 
+###### AutoGain for RTLSDR Devices
+
+If you have set `READSB_GAIN=autogain`, then the system will take signal strength measurements to determine the optimal gain. The AutoGain functionality is based on a (slightly) modified version of [Wiedehopf's AutoGain](https://github.com/wiedehopf/autogain). AutoGain will only work with `rtlsdr` style receivers.
+
+There are 2 distinct periods in which the container will attempt to figure out the gain:
+
+* The initial period of 90 minutes, in which a measurement is taken every 5 minutes
+* The subsequent period, in which a measurement is taken once every day
+
+Please note that in order for the initial period to complete, the container must run for 90 minutes without restarting.
+
+When taking measurements, if the percentage of "strong signals" (i.e., ADSB messages with RSSI > 3 dB) is larger than 7%, AutoGain will reduce the receiver's gain by 1 setting. Similarly, if the percentage of strong signals is smaller than 0.5%, AutoGain will increment the receiver's gain by 1 setting. When AutoGain changes the gain value, the `readsb` component of the container will restart. This may show as a disconnect / reconnected in container logs.
+
+Although not recommended, you can change the measurement intervals and low/high cutoffs with these parameters:
+
+| Environment Variable | Purpose | Default |
+|----------------------|---------|---------|
+| `READSB_AUTOGAIN_INITIAL_INTERVAL` | The measurement interval to optimize gain during the initial period of 90 minutes (in seconds) | `300` |
+| `READSB_AUTOGAIN_SUBSEQUENT_INTERVAL` | The measurement interval to optimize gain during the subsequent period (in seconds) | `86400` |
+| `READSB_AUTOGAIN_LOW_PCT` | If the percentage of "strong signals" (stronger than 3dBFS RSSI) is below this number, gain will be increased | `0.5` |
+| `READSB_AUTOGAIN_HIGH_PCT` | If the percentage of "strong signals" (stronger than 3dBFS RSSI) is above this number, gain will be decreased | `0.5` |
+
+If you need to reset AutoGain and start over determining the gain, you can do so with this command:
+
+```bash
+docker exec -it ultrafeeder /usr/local/bin/autogain1090 reset
+```
+
 #### Connecting to external ADSB data sources
 
 In addition to (or instead of) connecting to a SDR or hardware device to get ADSB data, the container also supports ingesting data from a TCP port. Here are some parameters that you need to configure if you want to make this happen:
@@ -326,7 +355,7 @@ All of the variables below are optional.
 | `GRAPHS1090_DISK_DEVICE` | Defines which disk device (`mmc0`, `sda`, `sdc`, etc) is shown. Leave empty for default device | Unset |
 | `GRAPHS1090_ETHERNET_DEVICE` | Defines which (wired) ethernet device (`eth0`, `enp0s`, etc) is shown. Leave empty for default device | Unset |
 | `GRAPHS1090_WIFI_DEVICE` | Defines which (wireless) WiFi device (`wlan0`, `wlp3s0`, etc) is shown. Leave empty for default device | Unset |
-| `GRAPHS1090_DISABLE` | Set to any value to disable the GRAPHS1090 web page | Unset |
+| `GRAPHS1090_DISABLE` | Set to any value to disable the GRAPHS1090 web page and data collection | Unset |
 | `ENABLE_AIRSPY` | Optional, set to any non-empty value if you want to enable the special AirSpy graphs. See below for additional configuration requirements | Unset |
 
 #### Enabling UAT data

rootfs/etc/services.d/autogain/run

@@ -0,0 +1,42 @@
+#!/usr/bin/with-contenv bash
+# shellcheck shell=bash disable=SC2076
+
+# Autogain routine
+#
+# Relevant env variables:
+#   READSB_GAIN: set to "autogain" to enable autogain
+#   READSB_AUTOGAIN_INITIAL_INTERVAL: time in seconds to run autogain during initial assessment period; 300 if omitted
+#   READSB_AUTOGAIN_SUBSEQUENT_INTERVAL: time in seconds to run autogain during initial assessment period; 86400 (=1 day) if omitted
+# Command to restart autogain: docker exec -it tar1090 /usr/local/bin/autogain1090 reset
+
+READSB_AUTOGAIN_INITIAL_INTERVAL="${READSB_AUTOGAIN_INITIAL_INTERVAL:-300}"
+READSB_AUTOGAIN_SUBSEQUENT_INTERVAL="${READSB_AUTOGAIN_SUBSEQUENT_INTERVAL:-86400}"
+
+if [[ "${READSB_GAIN,,}" != "autogain" ]]; then
+    # Autogain is not enabled, so let's do nothing forever
+    sleep infinity
+fi
+
+if [[ "${READSB_DEVICE_TYPE,,}" != "rtlsdr" ]] || [[ -z "${READSB_RTLSDR_DEVICE}" ]]; then
+    echo "[autogain] ERROR: AUTOGAIN enabled but READSB_DEVICE_TYPE is not \"rtlsdr\" or READSB_RTLSDR_DEVICE serial number not defined. Autogain disabled."
+    sleep infinity
+fi
+
+mkdir -p /var/globe_history/autogain
+
+# Do special things if it's the first time AUTOGAIN is running
+if [[ ! -f /var/globe_history/autogain/autogain_initialized ]]; then
+    # run autogain every $READSB_AUTOGAIN_INITIAL_INTERVAL minutes for 90 minutes
+    for (( i=0; i<$((5400/READSB_AUTOGAIN_INITIAL_INTERVAL)); i++ ))
+    do
+        sleep "$READSB_AUTOGAIN_INITIAL_INTERVAL"   # sleep first to give readsb the opportunity to collect some initial data
+        /usr/local/bin/autogain1090 2>&1 | mawk -W Interactive '{print "[autogain] " $0}'
+    done
+    touch /var/globe_history/autogain/autogain_initialized
+fi
+
+while true
+do
+    sleep "$READSB_AUTOGAIN_SUBSEQUENT_INTERVAL"
+    /usr/local/bin/autogain1090 2>&1 | mawk -W Interactive '{print "[autogain] " $0}'
+done

rootfs/etc/services.d/readsb/run

@@ -229,8 +229,15 @@ if [[ -n "$READSB_DEVICE_TYPE" ]]; then
     READSB_CMD+=("--device-type=$READSB_DEVICE_TYPE")
 fi
 
+# Handle "--gain"
 if [[ -n "$READSB_GAIN" ]]; then
-    READSB_CMD+=("--gain=$READSB_GAIN")
+    if [[ "${READSB_GAIN,,}" == "autogain" ]] && [[ -f /var/globe_history/autogain/gain ]]; then
+        read -r gain < /var/globe_history/autogain/gain
+        READSB_CMD+=("--gain=$gain") 
+    elif [[ -n "$READSB_GAIN" ]]; then
+        [[ "${READSB_GAIN,,}" == "autogain" ]] && gain="49.6" || gain="${READSB_GAIN}"
+        READSB_CMD+=("--gain=$gain")
+    fi
 fi
 
 ##### RTL-SDR OPTIONS #####

rootfs/usr/local/bin/autogain1090

@@ -0,0 +1,144 @@
+#!/usr/bin/with-contenv bash
+# shellcheck shell=bash
+
+low="${READSB_AUTOGAIN_LOW_PCT:-0.5}"
+high="${READSB_AUTOGAIN_HIGH_PCT:-7.0}"
+ga=(0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6 -10)
+tmp=/var/globe_history/autogain
+mkdir -p $tmp
+mkdir -p /var/globe_history/autogain
+
+#work around stupid locale stuff
+export LC_ALL=C
+
+APP=dump1090-fa
+if [[ -f /run/dump1090-fa/stats.json ]]; then
+    APP=dump1090-fa
+elif [[ -f /run/readsb/stats.json ]]; then
+    APP=readsb
+fi
+
+stats=/run/$APP/stats.json
+
+if [[ "$1" == "reset" ]]; then
+    echo "Reset AutoGain - restarting with initial values and initialization process"
+    rm -f /var/globe_history/autogain/* >/dev/null 2>&1
+    pkill -f "s6-supervise autogain"
+    exit 0
+fi
+
+if ! [[ -f $stats ]]; then echo "stats.json not found, is the decoder running?"; exit 1; fi
+
+oldstrong=$(cat $tmp/strong 2>/dev/null)
+oldtotal=$(cat $tmp/total 2>/dev/null)
+if [[ -z $oldstrong ]] || [[ -z $oldtotal ]]; then
+	oldstrong=0
+	oldtotal=0
+fi
+
+if ! grep -qs total $stats | grep -qs -e strong_signals $stats; then
+    echo "the decoder doesn't seem to be using an rtl-sdr device, can't help with that."
+    exit 1
+fi
+
+# start=$(jq '.total.start' < $stats)
+# end=$(jq '.total.end' < $stats)
+
+strong=$(jq '.total.local.strong_signals' < $stats | tee $tmp/strong)
+total=$(jq '.total.local.accepted | add' < $stats | tee $tmp/total)
+
+if [[ -z $strong ]] || [[ -z $total ]]; then
+    echo "unrecognized format: $stats"
+    exit 1
+fi
+
+if ! awk "BEGIN{ exit  ($total < 1000) }"; then
+    echo "The decoder hasn't been running long enough, wait a bit!"
+    exit 1
+fi
+
+
+if (( oldtotal > total )) || (( oldstrong > strong )) || (( oldtotal == total )); then
+	oldstrong=0
+	oldtotal=0
+fi
+
+strong=$((strong - oldstrong))
+total=$((total - oldtotal))
+
+if [[ $total == 0 ]]; then
+    percent=0
+else
+    percent=$(awk "BEGIN {printf \"%.3f\", $strong * 100 / $total}")
+fi
+
+strong=$percent
+
+if [[ $strong == "nan" ]]; then echo "Error, can't automatically adjust gain!"; exit 1; fi
+
+
+# Get the gain -- updated for docker-tar1090 use by kx1t
+if [[ ! -f /var/globe_history/autogain/gain ]]; then
+    oldgain="49.6"
+    echo "Initial run. Starting point for adjusting gain is $oldgain"
+else
+    read -r oldgain < /var/globe_history/autogain/gain
+    oldgain="${oldgain:-49.6}"    # needed for stupidity reasons
+fi
+
+gain_index=28
+for i in "${!ga[@]}"; do
+    if ! awk "BEGIN{ exit  (${oldgain} <= ${ga[$i]}) }"; then
+        gain_index="${i}"
+        break
+    fi
+done
+
+if ! awk "BEGIN{ exit  (${oldgain} > 49.6) }"; then
+    gain_index=28
+fi
+
+if [[ "$oldgain" == "-10" ]]; then
+    gain_index=28
+fi
+
+
+if ! awk "BEGIN{ exit ($strong > $low) }" && ! awk "BEGIN{ exit ($strong < $high) }"; then
+	echo "No gain change needed, percentage of messages >-3dB is in nominal range. (${strong}%)"
+	exit 0
+
+fi
+
+if ! awk "BEGIN{ exit ($strong < $low) }" && [[ $gain_index == 28 ]]; then
+    echo "Gain already at maximum! (${strong}% messages >-3dB)"
+    exit 0
+fi
+
+if ! awk "BEGIN{ exit ($strong < $low) }"; then
+    gain_index=$((gain_index+1))
+    action=Increasing
+fi
+
+if ! awk "BEGIN{ exit ($strong > $high) }" && [[ $gain_index == 0 ]]; then
+    echo "Gain already at minimum! (${strong}% messages >-3dB)"
+    exit 0
+fi
+
+if ! awk "BEGIN{ exit ($strong > $high) }"; then
+    gain_index=$((gain_index-1))
+    action=Decreasing
+fi
+
+gain="${ga[$gain_index]}"
+
+if [[ $gain == "" ]]; then echo "Gain already at maximum! (${strong}% messages >-3dB)"; exit 0; fi
+
+# Set the gain -- updated for docker-tar1090 use by kx1t
+echo "$gain" > /var/globe_history/autogain/gain
+pkill readsb
+
+#reset numbers
+echo 0 > $tmp/strong
+echo 0 > $tmp/total
+
+echo "$action gain to $gain (${strong}% messages >-3dB)"