diff --git a/src/algorithms/channel/adapters/channel.h b/src/algorithms/channel/adapters/channel.h
index 64cc81e36..bfbe9977d 100644
--- a/src/algorithms/channel/adapters/channel.h
+++ b/src/algorithms/channel/adapters/channel.h
@@ -86,7 +86,7 @@ public:
     inline std::shared_ptr<TrackingInterface> tracking() const { return trk_; }
     inline std::shared_ptr<TelemetryDecoderInterface> telemetry() const { return nav_; }
 
-    inline uint32_t fsm_state() { return channel_fsm_->state(); }
+    inline uint32_t fsm_state() const { return channel_fsm_->state(); }
 
 private:
     std::shared_ptr<ChannelFsm> channel_fsm_;
diff --git a/src/algorithms/channel/libs/channel_fsm.h b/src/algorithms/channel/libs/channel_fsm.h
index 15d5595ee..eb31013a7 100644
--- a/src/algorithms/channel/libs/channel_fsm.h
+++ b/src/algorithms/channel/libs/channel_fsm.h
@@ -58,7 +58,7 @@ public:
     virtual bool Event_failed_acquisition_repeat();
     virtual bool Event_failed_acquisition_no_repeat();
 
-    inline uint32_t state() { return state_; }
+    inline uint32_t state() const { return state_; }
 
 private:
     void start_tracking();