IS-95 셀룰라 시스템

김항래,김남 충북대학교 컴퓨터 정보통신 연구소 2000 컴퓨터정보통신연구 Vol.8 No.1

본 논문에서는 이동 무선채널을 레일레이(Rayleigy) 분포된 다중경로 페이딩 채널(multipath fading channel)로 가정한 IS-95 셀룰라 시스템의 역방향 링크에 대하여 활률식(blocking probability formula)을 유도한다. 얼랑용량은 음영효과(shadowing)만을 고려한 경우와 음영효과와 다중경로 페이딩을 모두 고려한 경우에 대하여 비교 분석된다. 2%의 블러킹 확률을 가정하면 데이터를 R?=9.6kbps에서는 19.97 얼랑, R?=14.4 kbps에서는 11.67얼랑으로 음영효과만을 고려한 경우보다 각각 16%와 19%의 용량이 감소하였다. IS-95 셀룰라 시스템에 대한 얼랑용량에서 다중경로 페이딩의 영향을 무시해서는 안되고 IS-95 셀룰라 시스템이 지원할 수 있는 정확한 얼랑용량과 등가채널수를 제공한다. In this paper, for the reverse link of a IS-95 cellular system assuming that a mobile radio channel is a Rayeigy distributed multipath fading channel, the blocking probability formula is derived. Erlang capacity in the case of considering shadowing is compared with that of considering both shadowing and multipath fading. Assuming that the blocking probability set 2%, the Erlang capacity is 19.97 Erlang at the data rate of R?=9.6 kbps and 11.67 Erlang at the data rate of R?=14.4 kbps and is less 16% and 19% than the Erlang capacity considering shadowing only, respectively. It is showed that the effect of multipath fading must not be ignored in Erlang capacity of the IS-95 cellular system and exact Erlang capacity and equivalent channel numbers that the IS-95 cellular system can support are provided.

IS-95 역방향링크 신호의 품질 측정 알고리즘

강성진(Kang, Sung-Jin),김남용(Kim, Nam-Yong) 한국산학기술학회 2010 한국산학기술학회논문지 Vol.11 No.9

본 논문에서는 IS-95 역방향링크 신호의 품질 측정을 위한 알고리즘을 제안하고 구현하였다. 수신 신호의 품 질을 측정하기 위해서는 등화, 반송파 주파수 및 위상 오프셋 추정, 타이밍 동기가 반드시 필요하며, 모든 신호처리는 기저대역에서 수행된다. 등화기는 칩간 간섭(InterChip Interference)을 제거하기 위해, 4배 오버샘플링된 샘플에 대해서 동작하도록 설계되었다. 반송파 주파수 및 위상 오프셋 추정은 데이터 및 타이밍 정보 없이도 가능하도록 하였기 때 문에, 타이밍 동기 이전에 수행된다. 타이밍 동기 시에 사용되는 보간 수(Interpolation Number)에 따라 측정의 정확도 가 증가하지만, 계산량도 증가하게 된다. 따라서, 제안된 알고리즘이 구현될 플랫폼 성능에 따라 보간 수를 적절히 선 택해야한다. In this paper, we proposed and implemented a quality measurement algorithm for IS-95 reverse-link signal. To measure the quality of the received signal, equalization, carrier frequency/phase offset estimation, and timing synchronization are essential. And, all signal processing are carried out with baseband signal. The equalizer works with 4-oversampled samples to remove ICI(InterChip Interference). The frequency/phase offset estimator is followed by timing synchronizer since it can work without aid of data and timing information. As the number of interpolation in timing synchronization increases, the measurement accuracy improves, but computation load increases simultaneously. Therefore, one need to choose adequately the number of interpolation regarding to the platform performance to be used for the proposed algorithm.

cdma2000 Physical Layer: An overview

Willenegger, Serge The Korean Institute of Communications and Informa 2000 Journal of communications and networks Vol.2 No.1

cdma2000 offers several enhancement as compared to TIA/EIA-95, although it remains fully compatible with TIA/EIA-95 systems and allows for a smooth migration from one to the other-Major new capability include:1)connectivity to GSM-MAP in addition to IP and IS-41 networks; 2) new layering with new LAC and MAC architectures for improved service multiplexing and QoS management and efficient use of radio resource ;3) new bands and band widths of operation in support of various operator need and constraints, as well as desire for a smooth and progressive migration to cdma 2000; and 4) flexible channel structure in support of multiple services with various QoS and variable transmission rates at up to 1 Mbps per channel and 2 Mbps per user. Given the phenomenal success of wireless services and desire for higher rate wireless services. improved spectrum efficiency was a major design goal in the elaboration of cdma2000. Major capacity enhancing features include; 1) turbo coding for data transmission: 2)fast forward link power control :3) forward link transmit diversity; 4) support of directive antenna transmission techniques; 5) coherent reverse link structure; and 6) enhanced access channel operation. As users increasingly rely on their cell phone at work and at home for voice and data exchange, the stand-by time and operation-time are essential parameters that can influence customer's satisfaction and service utilization. Another major goal of cdma2000 was therefore to enable manufacturers to further optimize power utilization in the terminal. Major battery life enhancing features include; 1) improved reverse link performance (i.e., reduced transmit power per information bit; 2) new common channel structure and operation ;3) quick paging channel operation; 4) reverse link gated transmission ; and 5) new MAC stated for efficient and ubiquitous idle time idle time operation. this article provides additional details on those enhancements. The intent is not to duplicate the detailed cdma2000 radio access network specification, but rather to provide some background on the new features of cdma2000 and on the qualitative improvements as compared to the TIA/EIA-95 based systems. The article is focused on the physical layer structure and associated procedures. It therefore does not cover the MAC, LAC, radio resource management [1], or any other signaling protocols in any detail. We assume some familiarity with the basic CDMA concepts used in TIA/EIA-95.

CDMA2000-1x 이동통신망 공통비용 배분기준에 관한 연구

김문수 국립7개대학공동논문집간행위원회 2005 공업기술연구 Vol.5 No.-

In most countries, the telecommunication service charges have been regulated by based on the costs since the competition was introduced in the telecommunication market. Today, several and various services can be provided from the one network so it leads to regulator's intervention on accounting separation per service and common cost allocation in accounting separation. Especially, how to allocate common costs has influenced user's utility of own or other network. We consider the voice service from the IS 95 mobile network as an existing service and data service and others from the cdma2000-1x as new ones. Under the circumstance, the several problems, which are caused by applying an existing cost allocation criterion to today's network, are examined. Those are happened where common systems are shared by voice and data services in the cdma2000-1x mobile network. Therefore, we propose a new allocation standard based on the characteristics of cdma2000-1x system to settle those problems.

SIR 기반의 셀룰러 무선망에서 전송 전력 제어 알고리듬의 성능 비교

정보환(Bo-Hwan Jung),김문갑(Moon-Gab Kim) 대한전자공학회 2009 電子工學會論文誌-TC (Telecommunications) Vol.46 No.5

이 논문에서는 SIR 기반의 셀룰러 무선망에서 전송 전력 제어 알고리듬들의 성능을 수치실험을 통해 평가하였다. 이를 위해 SIR 기반의 연속 및 이산 시간 전송 전력 제어 알고리듬을 하나로 통합된 동적 상태 방정식으로 표현하였다. 수치실험은 연속성을 갖는 외란 환경 하에서 수행되었다. 수치실험 결과 본 논문에서 제안한 전송 전력 제어 알고리듬이 보다 우수한 외란 제거 성능을 명백히 보여 준다. In this paper, we evaluate a performance on a transmission power control algorithm in a SIR-based wireless networks. We consider the existing iterative power control algorithms into a unified dynamic state system formulation in both continuous-time and discrete-time system. Numerical experiments are performed under the disturbance of sinusoidal. These results indicate that the proposed power control scheme has a performance improvement with a better disturbance elimination in wireless mobile systems.

항공 통신 기술 분야 : 호 폭주 비상재난통신 디지털 TRS(Trunked Radio System) 수신채널할당 기법

이순화 ( Soon Hwa Lee ),오갑근 ( Kab Keun Oh ),홍완표 ( Wan Pyo Hong ) 韓國航行學會 2009 韓國航行學會論文誌 Vol.13 No.6