We have updated the 3GPP/LTE ASN.1 API's we have available for use with ASN1C. These API's are extended sample programs that contain the complete ASN.1 specifications extracted from the relevant 3GPP standard documents. The API's are available at the following URL:
http://www.obj-sys.com/lte_3gpp_apis.php
There are now API's available for 3GPP release 8, 9, and 10 of the different specification types. API's are currently available for the LTE-RRC, S1AP, andX2AP LTE ASN.1 specifications. Updated API's will soon be made available for 3G ASN.1 specifications as well such as NBAP and RANAP.