diff --git a/broadcastradio/1.0/types.hal b/broadcastradio/1.0/types.hal
index e9ac4b7..8c3ec11 100644
--- a/broadcastradio/1.0/types.hal
+++ b/broadcastradio/1.0/types.hal
@@ -212,12 +212,23 @@
     uint32_t     channel;   /** current channel. (e.g kHz for band type AM_FM) */
     uint32_t     subChannel; /** current sub channel. (FM_HD) */
 
-    /** Tuned to a program (not a noise). It's the same condition that would stop scan operation. */
+    /**
+     * Tuned to a program (not a noise). It's the same condition that would
+     * stop scan operation.
+     */
     bool         tuned;
 
     bool         stereo;    /** program is stereo or not */
     bool         digital;   /** digital program or not (e.g HD Radio program) */
-    uint32_t     signalStrength; /** signal strength from 0 to 100 */
-    vec<MetaData> metadata; /** non empty if meta data are present (e.g PTY, song title ...) */
+
+    /**
+     * Signal quality measured in 0% to 100% range.
+     *
+     * Despite the name, this is not a signal strength.
+     * The purpose of this field is primarily informative.
+     */
+    uint32_t signalStrength;
+
+    vec<MetaData> metadata; /** Metadata: PTY, song title etc. */
 };
 
diff --git a/broadcastradio/1.1/ITuner.hal b/broadcastradio/1.1/ITuner.hal
index a5c569a..cc2e58d 100644
--- a/broadcastradio/1.1/ITuner.hal
+++ b/broadcastradio/1.1/ITuner.hal
@@ -84,6 +84,13 @@
      * subsequent calls to startBackgroundScan, issuing a single
      * backgroundScanComplete callback.
      *
+     * If a device supports continuous background scanning, it may succeed
+     * (return OK and call backgroundScanComplete) without any additional
+     * operation performed.
+     *
+     * Foreground scanning may be implemented in the front end app with
+     * @1.0::ITuner scan operation.
+     *
      * @return result OK if the scan was properly scheduled (this does not mean
      *                it successfully finished).
      *                UNAVAILABLE if the background scan is unavailable,