모바일 셀룰러 망에서 Class-Based LPRR 예측기법을 이용한 동적가드채널 할당기법

이진이(Jinyi Lee) 한국정보기술학회 2006 한국정보기술학회논문지 Vol.4 No.6

A large amount of research has been focusing on call admission control to provided the quality-of-service(QoS) guarantees to multimedia user applications in mobile cellular networks. Also the intensive researches on the channel assignment problem have been making to improve the efficient use of limited radio spectrum. In this paper, we introduce a dynamic channel allocation scheme for reducing real-handoff dropping rate as well as improving the efficiency of resource utilization. Our scheme utilizes a class-based local prediction resource reservation(LPRR) to enhance the existing GCS' performance in reducing of real-time handoff calls dropping rate. The purpose of this paper is to reduce real-time handoff call dropping rate. For this purpose, our scheme classifies service calls into new calls, non-realtime handoff calls and real-time handoff calls, and reserve a demanded channel number predicted by LMS-Wiener prediction model of LPRR for only real-time handoff calls. Therefore guard channel numbers reserved for real-time handoff calls varies dynamically. The simulation results shows that the proposed scheme outperforms the GCS in the real-time handoff calls' dropping rate and the efficiency of channel utilization.

Radio Resource Management Scheme for Heterogeneous Wireless Networks Based on Access Proportion Optimization

Shi, Zheng,Zhu, Qi The Korea Institute of Information and Commucation 2013 Journal of communications and networks Vol.15 No.5

Improving resource utilization has been a hot issue in heterogeneous wireless networks (HWNs). This paper proposes a radio resource management (RRM) method based on access proportion optimization. By considering two or more wireless networks in overlapping regions, users in these regions must select one of the networks to access when they engage in calls. Hence, the proportion of service arrival rate that accesses each network in the overlapping region can be treated as an optimized factor for the performance analysis of HWNs. Moreover, this study considers user mobility as an important factor that affects the performance of HWNs, and it is reflected by the handoff rate. The objective of this study is to maximize the total throughput of HWNs by choosing the most appropriate factors. The total throughput of HWNs can be derived on the basis of a Markov model, which is determined by the handoff rate analysis and distribution of service arrival rate in each network. The objective problem can actually be expressed as an optimization problem. Considering the convexity of the objective function, the optimization problem can be solved using the subgradient approach. Finally, an RRM optimization scheme for HWNs is proposed. The simulation results show that the proposed scheme can effectively enhance the throughput of HWNs, i.e., improve the radio resource utilization.

Radio Resource Management Scheme for Heterogeneous Wireless Networks based on Access Proportion Optimization

Zheng Shi,Qi Zhu 한국통신학회 2013 Journal of communications and networks Vol.15 No.5

Improving resource utilization has been a hot issue in heterogeneouswireless networks (HWNs). This paper proposes a radioresource management (RRM) method based on access proportionoptimization. By considering two or more wireless networks inoverlapping regions, users in these regions must select one of thenetworks to access when they engage in calls. Hence, the proportionof service arrival rate that accesses each network in the overlappingregion can be treated as an optimized factor for the performanceanalysis of HWNs. Moreover, this study considers usermobility as an important factor that affects the performance ofHWNs, and it is reflected by the handoff rate. The objective of thisstudy is to maximize the total throughput of HWNs by choosingthe most appropriate factors. The total throughput of HWNs canbe derived on the basis of a Markov model, which is determinedby the handoff rate analysis and distribution of service arrival ratein each network. The objective problem can actually be expressedas an optimization problem. Considering the convexity of the objectivefunction, the optimization problem can be solved using thesubgradient approach. Finally, an RRM optimization scheme forHWNs is proposed. The simulation results show that the proposedscheme can effectively enhance the throughput of HWNs, i.e., improvethe radio resource utilization.

이동통신 환경에서 핸드오프를 고려한 SIR 기반의 상향 링크 고정채널 알고리즘의 성능 측정

이현희,김동회 강원대학교 정보통신연구소 2008 정보통신논문지 Vol.12 No.-

The channel allocation in a cellular system is important form the performance analysis. Channel allocation usually deals with how a BS(Base Station) should assign traffic channels to the MS(Mobile Station)s. Also, handoff basically involves change of radio resources from one cell to another adjacent cell. From a handoff perspective, it is important that a free channel is available in a new cell whenever handoff generates, so that undisrupted service is available. This paper deals with a difference of performance in terms of new call blocking probability and forced termination probability between SIR-based FCA(Fixed Channel allocation) strategy without supporting handoff operation and SIR-based FCA strategy with supporting handoff operation in wireless communication network. From the simulation results, we find that SIR-based FCA strategy with supporting handoff operation has better performance than SIR-based FCA strategy without supporting handoff operation.

MMOSPRED 무선자원 예측방법을 이용한 무선망의 이동성예측 자원할당

이진이(Jinyi Lee) 한국정보기술학회 2007 한국정보기술학회논문지 Vol.5 No.3

In order to utilize scarce resource more efficiently in wireless networks, we predict the call's desired amount of resource, and then reserve it in cells. This paper suggests a mobility predictive resource allocation scheme using a resource demands prediction method MMOSPRED(Multimedia One Step Prediction) algorithm to make the channel allocation more efficient. The existing GCS(Guard Channel Scheme) would decrease channel utilization when handoff calls happen rarely. The proposed resource prediction and reservation method increases the resource utilization while decreasing handoff dropping rate in comparison with GCS. The proposed scheme predicts the handoff call's demanded amount by using MMOSPRED algorithm, and reserving dynamically it in a central celll. The MMOSPRED algorithm decides a call’s desired amount of resource based on neighboring cell information and probabilities that a user will move to adjacent cells, The performance of the proposed schemes studies using computer simulation. Results show that ours method can achieve the better resource utilization while reducing handoff dropping rate than GCS method.

무선 인지 셀룰러 망에서 자원예측에 의한 가드채널 할당기법의 성능개선

이진이 ( Jin Yi Lee ) 한국항행학회 2012 韓國航行學會論文誌 Vol.16 No.5

본 논문에서는 셀룰러 기반 무선 인지망에서 핸드오프 호를 위한 가드채널할당기법(guard channel scheme)의 자원이용률의 저하를 개선하기 위해 무선인지 기술을 사용하여 자원 이용률을 향상시키면서, 무선 인지망의 부 사용자(cognitive radio user) 손실률을 줄이는 방법을 제안한다. 제안한 방법에서는 핸드오프 호의 전용채널(guard channel)을 부 사용자가 이용하도록 하고, MMOSPRED(Multi-Media One Step Prediction)기법으로 핸드오프 호의 발생을 예측한 다음, 핸드오프 호가 발생하면 핸드오프 호의 전용채널을 넘겨주고, 부 사용자는 예약된 자원으로 스펙트럼 핸드오프를 하여 서비스를 완료 하도록 한다. 시뮬레이션을 통하여, 제안한 기법의 자원 이용률과 부 사용자의 손실률에 대한 성능이 기존의 가드채널 할당기법과 모바일의 이동성을 예측하지 않은 채널할당기법 보다 우수함을 보인다. In this paper, we propose a scheme for improving not only the utilization of frequency bands in the guard channel scheme but also the dropping rate of cognitive radio user in the wireless cognitive radio-based cellular network. The proposed scheme enables cognitive radio users to utilize the guard channel for servicing only handoff calls in normal times, but cognitive radio users must vacate the frequency channel when handoff call appearing. At this time our scheme ensures their seamless services for cognitive radio users, by predicting handoff call`s appearance by MMOSPRED (Multi-Media One Step Prediction) method and then reserving the demanded channels for spectrum handoff calls. Our simulations show that our scheme performs better than other schemes; GCS(Guard Channel Scheme) and a scheme without prediction in terms of cognitive users call`s dropping rate and resource utilization efficiency.

기반 기술 : 무선인지 통신망에서 스펙트럼 홀 예측에 의한 채널할당

이진이 ( Jin Yi Lee ) 한국항행학회 2015 韓國航行學會論文誌 Vol.19 No.4

무선통신망에서 예측기법을 이용하는 경우는 대부분 사용자호가 요구하는 자원의 크기를 예측하여 미리 요구자원을 예약함으로써 사용자호가 요구하는 품질을 보장한다. 그러나 본 논문에서는 무선인지통신망에서 면허사용자가 사용하지 않는 스펙트럼홀 (spectrum hole)자원의 크기를 예측하여 대여사용자의 스펙트럼 핸드오프호의 서비스 품질을 향상시킬 수 있는 채널할당방법을 제안한다. 스펙트럼홀의 예측은 위너예측모델을 이용한다. 채널할당 방법은 대여사용자호를 초기 발생호와 스펙트럼 핸드오프호로 구분하고, 예측된 스펙트럼홀 자원의 일정부분을 예약하여 스펙트럼 핸드오프호에 우선적으로 할당한다. 시뮬레이션을 통하여 제안한 기법이 스펙트럼홀 예측을 사용하지 않는 방법보다 대여사용자의 스펙트럼 핸드오프호의 서비스 품질을 향상(50% 예약시 평균 11% 개선)시킬 수 있음을 보인다. In wireless communication networks, most of the prediction techniques are used for predicting the amount of resource required by user``s calls for improving their demanding quality of service. However, we propose a channel allocation scheme based on predicting the resources of white spectrum holes for improving the QoS of rental user``s spectrum handoff calls for cognitive radio networks in this paper. This method is supported by Wiener predictor to predict the amount of white spectrum holes of license user``s free spectrum resources. We classify rental user``s calls into initial calls and spectrum handoff calls, and some portion of predicted spectrum-hole resources is reserved for spectrum handoff calls`` priority allocation. Simulations show that the performance of the proposed scheme outperforms in spectrum handoff call``s dropping rate than an existing method without spectrum hole prediction(11% average improvement in 50% reservation).

이동 통신망에서 위너필터 예측에 의한 대역폭예약 할당기법

이진이(Jinyi Lee) 한국정보기술학회 2007 한국정보기술학회논문지 Vol.5 No.4

In wireless mobile networks, the amount of bandwidths required by connections can be predicted and reserved to service coming mobile hosts. This paper presents a bandwidth reservation allocation method based on Wiener prediction theory in predicting and reserving its demands for future handoff connections. The proposed method has the potential to improve on CDP(connection dropping probability) for handoff connections by predicting and reserving their bandwidth demands, and it can also improve on resource utilization by predicting resource requirements with accuracy. Wiener-based on prediction method can predict the amount of resource required by handoff connections at a future time with past resource demands. So, this scheme is much simpler to implement than mobility prediction resource reservation scheme which needs estimation of connection arrival process, per-connection bandwidth demand, estimation of connection and channel holding time distribution, and so on. Also Wiener-based on prediction scheme remains equal prediction performance with mobility-based on prediction scheme[1]. We compare via simulation the performance of the proposed methods with the existing GCAS(guard channel allocation scheme)in terms of CDR, CBR, and bandwith utilization. The results reveal that our proposed bandwidth allocation method generates better performance than the existing GCAS method.

셀룰러 인지 라디오 망에서 스펙트럼 홀 그룹핑에 의한 인지 사용자의 서비스 품질향상

이진이 한국항행학회 2019 韓國航行學會論文誌 Vol.23 No.4

In this paper, we propose first a scheme of grouping spectrum holes that are created in the multiple channels of primary users, and then by using the scheme we enhance quality of service (QoS) of wideband cognitive radio users in cellular cognitive radio networks. In our scheme, spectrum holes created in each primary channel are predicted by Wiener prediction process, and then the predicted spectrum holes happened in the same time are grouped into a group. The wideband cognitive radio users explore the group of spectrum holes to improve their QoS. Simulation results show that their handoff calls dropping rate and initial calls blocking rate are significantly reduced in our scheme, compared to those in the single primary channel. 본 논문에서는 셀룰러 인지 라디오 망에서 주 사용자들 (PU; primary user)의 다중 채널상에서 발생하는 스펙트럼 홀 (spectrum hole)을 그룹핑(grouping)하여, 광대역 인지 사용자 (WCRU; wideband cognitive radio user)의 서비스 품질 (QoS; quality of service)을 향상시킬 수 있는 방법을 제안한다. 제안하는 스펙트럼 홀 그룹핑 방법은 같은 시간에 발생하는 스펙트럼 홀들을 위너예측과정으로 예측하고, 예측된 스펙트럼 홀을 그룹핑하여 광대역 인지 사용자를 지원함으로써 인지 사용자의 서비스 품질을 향상시킨다. 시뮬레이션을 통하여 단일 스펙트럼 홀 채널을 이용한 경우와 비교하여 핸드오프 호의 손실률과 초기 발생 호의 차단률을 줄일 수 있음을 보인다.

이동국의 셀 거주 시간 분포 유도 및 성능 비교

진고환 우송대학교 2004 우송대학교 논문집 Vol.9 No.-

This paper addresses mobility models for the exact analysis of performance in cellular networks. The probability density functions of speed and direction of terminal crossing a cell boundary, based on "Biased Sampling" formula, are unequal to the probability density functions for terminals in the cell. A more precise mobility model is first derived on a single isolated cell with a circular boundary. The model is then compared with Tomas's, Hong's, and Xie's ones in the well-known performance measures. A computer simulation is also conducted to illustrate the accuracy of the proposed mobility model.