A-bis interface dimensioning for EGPRS technology

The introduction of a new technology, EGPRS (enhanced general packet radio service), in the former existing GSM/GPRS networks requires a detailed analysis of the impact in the existing networks and an accurate estimation of the additional resource requirements. The paper focuses on the impact of the introduction of EGPRS technology in the A-bis interface. The A-bis interface is based on pulse code modulation (PCM). The main impact analyzed is the additional need of A-bis resources for each radio timeslot occupied by an EGPRS user. The paper presents the A-bis pool concept, and introduces an analytical model for the dimensioning of the optimum size of this A-bis pool. Finally, a comparison with real network results is presented.