Resolves #663. Updates P25 phase 2 Decoder to detect PLL lock errors for +/-90 and 180 out-of-phase. Adds support for broadcasting phase 2 channel frequency error calculations to support tuner auto-correction for frequency errors. Removes adaptive PLL bandwidth support from Phase 1 and uses a fixed PLL bandwidth for both phase 1 and phase 2 decoders. Updates the Phase 2 symbol timing gain with results from extensive testing of PLL bandwidth and symbol timing combinations. (#666)

src/main/java/io/github/dsheirer/module/decode/FeedbackDecoder.java

@@ -0,0 +1,65 @@
+/*
+ *
+ *  * ******************************************************************************
+ *  * Copyright (C) 2014-2020 Dennis Sheirer
+ *  *
+ *  * This program is free software: you can redistribute it and/or modify
+ *  * it under the terms of the GNU General Public License as published by
+ *  * the Free Software Foundation, either version 3 of the License, or
+ *  * (at your option) any later version.
+ *  *
+ *  * This program is distributed in the hope that it will be useful,
+ *  * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  * GNU General Public License for more details.
+ *  *
+ *  * You should have received a copy of the GNU General Public License
+ *  * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *  * *****************************************************************************
+ *
+ *
+ */
+
+package io.github.dsheirer.module.decode;
+
+import io.github.dsheirer.sample.Listener;
+import io.github.dsheirer.source.ISourceEventProvider;
+import io.github.dsheirer.source.SourceEvent;
+
+/**
+ * Decoder that provides feedback to signal source(s) via SourceEvent broadcasts and supports registering source
+ * event listeners.
+ */
+public abstract class FeedbackDecoder extends Decoder implements ISourceEventProvider
+{
+    private Listener<SourceEvent> mSourceEventListener;
+
+    /**
+     * Registers the listener to receive source events from this decoder
+     */
+    @Override
+    public void setSourceEventListener(Listener<SourceEvent> listener)
+    {
+        mSourceEventListener = listener;
+    }
+
+    /**
+     * Deregisters the listener from receiving source events from this decoder.
+     */
+    @Override
+    public void removeSourceEventListener()
+    {
+        mSourceEventListener = null;
+    }
+
+    /**
+     * Broadcasts the specified source event to the optional registered source event listener
+     */
+    public void broadcast(SourceEvent sourceEvent)
+    {
+        if(mSourceEventListener != null)
+        {
+            mSourceEventListener.receive(sourceEvent);
+        }
+    }
+}