Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7

diversity gain Related Abstracts

7 Improved Performance of Cooperative Scheme in the Cellular and Broadcasting System

Authors: Hyoung-Kyu Song, Bit-Na Kwon, Yong-Jun Kim, Hyun-Jee Yang

Abstract:

In the cooperative transmission scheme, both the cellular system and broadcasting system are composed. Two cellular base stations (CBSs) communicating with a user in the cell edge use cooperative transmission scheme in the conventional scheme. In the case that the distance between two CBSs and the user is distant, the conventional scheme does not guarantee the quality of the communication because the channel condition is bad. Therefore, if the distance between CBSs and a user is distant, the performance of the conventional scheme is decreased. Also, the bad channel condition has bad effects on the performance. The proposed scheme uses two relays to communicate well with CBSs when the channel condition between CBSs and the user is poor. Using the relay in the high attenuation environment can obtain both advantages of the high bit error rate (BER) and throughput performance.

Keywords: OFDM, cooperative communications, diversity gain, interworking system

Procedia PDF Downloads 408
6 Hybrid MIMO-OFDM Detection Scheme for High Performance

Authors: Hyoung-Kyu Song, Dong-Hyun Ha, Chang-Bin Ha, Young-Min Ko

Abstract:

In recent years, a multi-antenna system is actively used to improve the performance of the communication. A MIMO-OFDM system can provide multiplexing gain or diversity gain. These gains are obtained in proportion to the increase of the number of antennas. In order to provide the optimal gain of the MIMO-OFDM system, various transmission and reception schemes are presented. This paper aims to propose a hybrid scheme that base station provides both diversity gain and multiplexing gain at the same time.

Keywords: Hybrid, mimo, DFE, diversity gain, multiplexing gain

Procedia PDF Downloads 421
5 Adaptive Cooperative Scheme Considering the User Location

Authors: Hyoung-Kyu Song, Bit-Na Kwon, Dong-Hyun Ha, Hyun-Jee Yang

Abstract:

In this paper, an adaptive cooperative scheme in the cell edge is proposed. The proposed scheme considers the location of a user and applies the suitable cooperative scheme. In cellular systems, the performance of communication is degraded if the user is located in the cell edge. In conventional scheme, two base stations are used in order to obtain diversity gain. However, the performance of communication is not sufficiently improved since the distance between each base station and a user is still distant. Therefore, we propose a scheme that the relays are used and the cooperative scheme is adaptively applied according to the user location. Through simulation results, it is confirmed that the proposed scheme has better performance than the conventional scheme.

Keywords: OFDM, Cooperative Communication, diversity gain, adaptive transmission

Procedia PDF Downloads 399
4 Cooperative Diversity Scheme Based on MIMO-OFDM in Small Cell Network

Authors: Hyoung-Kyu Song, Dong-Hyun Ha, Chang-Bin Ha, Young-Min Ko

Abstract:

In Heterogeneous network (HetNet) can provide high quality of a service in a wireless communication system by composition of small cell networks. The composition of small cell networks improves cell coverage and capacity to the mobile users.Recently, various techniques using small cell networks have been researched in the wireless communication system. In this paper, the cooperative scheme obtaining high reliability is proposed in the small cell networks. The proposed scheme suggests a cooperative small cell system and the new signal transmission technique in the proposed system model. The new signal transmission technique applies a cyclic delay diversity (CDD) scheme based on the multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) system to obtain improved performance. The improved performance of the proposed scheme is confirmed by the simulation results.

Keywords: OFDM, Cooperative Communication, diversity gain, adaptive transmission

Procedia PDF Downloads 377
3 Improved Cooperative Communication Scheme in the Edge of Cell Coverage

Authors: Hyoung-Kyu Song, Myoung-Jin Kim, Hyun-Jee Yang, Yeong-Seop Ahn

Abstract:

This paper proposes the new cooperative communication scheme for the wireless communication system. When the receiver is located in the edge of coverage, the signal from the transmitter is distorted by the inter-cell interference (ICI) and power reduction by distance. In order to improve communication performance, the proposed scheme adds the relay. By using the relay, the receiver receives the signal from the transmitter and relay at the same time. Therefore, the new cooperative communication scheme obtains diversity gain and is improved by the relay.

Keywords: OFDM, mimo, Cooperative Communication, diversity gain

Procedia PDF Downloads 424
2 Cooperative AF Scheme for Multi Source and Terminal in Edge of Cell Coverage

Authors: Hyoung-Kyu Song, Chang-Bin Ha, Myoung-Jin Kim, Yeong-Seop Ahn

Abstract:

This paper proposes a cooperative communication scheme for improve wireless communication performance. When the receiver is located in the edge of coverage, the signal from the transmitter is distorted for various reasons such as inter-cell interference (ICI), power reduction, incorrect channel estimation. In order to improve communication performance, the proposed scheme adds the relay. By the relay, the receiver has diversity gain. In this paper, two base stations, one relay and one destination are considered. The two base stations transmit same time to relay and destination. The relay forwarding to destination and the destination detects signals.

Keywords: OFDM, Cooperative Communication, MMSE, diversity gain

Procedia PDF Downloads 267
1 Cooperative Scheme Using Adjacent Base Stations in Wireless Communication

Authors: Seung-Jun Yu, Hyoung-Kyu Song, Chang-Bin Ha, Young-Min Ko

Abstract:

In a wireless communication system, the failure of base station can result in a communication disruption in the cell. This paper proposes a way to deal with the failure of base station in a wireless communication system based on OFDM. Cooperative communication of the adjacent base stations can be a solution of the problem. High performance is obtained by the configuration of transmission signals which is applied CDD scheme in the cooperative communication. The Cooperative scheme can be a effective solution in case of the particular situation.

Keywords: OFDM, mimo, base station, CDD, diversity gain

Procedia PDF Downloads 243