مرکز منطقه ای اطلاع رسانی علوم و فناوری Journal of Information Systems and Telecommunication (JIST) 2322-1437 14 53 2026 6 29 Re-CAC: A Re-Engineered Call Admission Control for LTE Downlink Networks Using Stepwise Bandwidth Degradation Concept Re-CAC: A Re-Engineered Call Admission Control for LTE Downlink Networks Using Stepwise Bandwidth Degradation Concept 16 27 en Vitalis Onyeke University of Nigeria, Nsukka Udora Nwawelu University of Nigeria, Nsukka Bonaventure Ekengwu University of Nigeria, Nsukka Nnaemeka Asiegbu University of Nigeria, Nsukka Benjamin Ezurike Alex Ekwueme Federal University, Ndufu-Alike Dumtochukwu Oyeka University of Nigeria, Nsukka Chukwudi Chukwudozie University of Nigeria, Nsukka Chimdalu Okide University of Nigeria, Nsukka 2024 9 24 <p><a name="_Hlk176418633"></a><span style="font-size: 10.0pt; font-family: 'Times New Roman',serif; mso-fareast-font-family: 'MS Mincho'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA; mso-bidi-font-weight: bold;">This work presents a Re-engineered Call Admission Control (Re-CAC) scheme for long term evolution (LTE) downlink networks. The scheme is timely as communication networks become increasingly heterogeneous with ever increasing number of subscribers with different Quality of Service (QoS) requests. Bandwidth degradation is an effective concept that some Call Admission Control (CAC) schemes have employed to provide an improved QoS to the admitted RT calls. However, it has led to noticeable resource wastage due to inappropriate degradation method employed. As promising panacea, stepwise bandwidth degradation is employed in this work. This contribution allows sequential bandwidth degradation in stepwise manner. The work demonstrated through extensive simulations in MATLAB the effectiveness of the proposed concept on the basis of throughput, call blocking probability (CBP), call dropping probability (CDP), and spectral efficiency metrics. </span><span style="font-size: 10.0pt; font-family: 'Times New Roman',serif; mso-fareast-font-family: 'MS Mincho'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA; mso-bidi-font-weight: bold;">The results show that </span><span style="font-size: 10.0pt; font-family: 'Times New Roman',serif; mso-fareast-font-family: 'MS Mincho'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">Re-CAC scheme achieved an average throughput of 0.1657 Mbps and 0.0932 Mbps of RT and NRT calls, respectively; 0.0837 and 0.0650 CBP of RT and NRT calls, correspondingly; respective 0.0733 and 0.0763 CDP of RT and NRT calls; and spectral efficiency of 0.0331 bps/Hz and 0.0191 bps/Hz of RT and NRT calls, respectively. <a name="_Hlk176419990"></a>The Re-CAC scheme is benchmarked with quality of service-aware CAC (QA-CAC), adaptive CAC (ACAC), and enhanced adaptive CAC (EA-CAC) schemes. The superiority of Re-CAC scheme over the benchmark CAC schemes in handling RT services is demonstrated and this was achieved without sacrificing the performance of NRT calls</span></p> http://jist.ir/ar/Article/Download/48095