diff --git a/lib/trx_interface/trx_impl.h b/lib/trx_interface/trx_impl.h
index 41a4788..29545b1 100644
--- a/lib/trx_interface/trx_impl.h
+++ b/lib/trx_interface/trx_impl.h
@@ -45,6 +45,7 @@
       ~trx_impl();
 
       void handle_dl_burst(pmt::pmt_t msg);
+      void handle_ul_burst(uint8_t *payload, size_t len);
     };
 
   } // namespace grgsm