Abstract :
Draft new ITU-T Recommendation G.826 specifies error performance parameters and objectives for international digital paths at or above the primary rate. These paths may be based on a PDH, SDH or some other transport network. Future radio-relay systems, which will form part of these paths have to comply with this recommendation. The present paper analyzes the new concepts introduced in G.826 and applies them to radio-relay systems. It will be shown that the performance requirements of G.826 are more stringent than those in the present recommendations based on G.821. This may result in a reduction of the achievable hop lengths; several calculated examples are given. Lastly, some countermeasures to overcome the limitations of G.826 are discussed