diff --git a/library/GSMTAP_Types.ttcn b/library/GSMTAP_Types.ttcn
index 3288284..76e6ea3 100644
--- a/library/GSMTAP_Types.ttcn
+++ b/library/GSMTAP_Types.ttcn
@@ -1,5 +1,6 @@
 module GSMTAP_Types {
 	import from Osmocom_Types all;
+	import from GSM_Types all;
 
 	const uint8_t GSMTAP_VERSION	:= 2;
 
@@ -49,7 +50,7 @@
 		uint8_t		hdr_len,
 		GsmtapMsgType	msg_type,
 		uint8_t		timeslot,
-		Arfcn		arfcn,
+		GsmBandArfcn	arfcn,
 		int8_t		signal_dbm,
 		int8_t		snr_db,
 		uint32_t	frame_number,