计算机工程与应用
計算機工程與應用
계산궤공정여응용
COMPUTER ENGINEERING AND APPLICATIONS
2013年
18期
56-60
,共5页
高速铁路%多波束%机会波束赋形
高速鐵路%多波束%機會波束賦形
고속철로%다파속%궤회파속부형
high speed railway%multi-beam%opportunistic beamforming
鉴于高速铁路通信中,列车位置信息可预测、列车车顶中继转发天线数有限,以及反馈信息时延大、多普勒衰落较大、频繁切换等特性,传统的波束赋形并不适用于高速铁路场景。位置信息辅助的多波束机会波束赋形能够利用列车位置信息可预测的优势,在机会波束赋形算法中有效地提高发送波束随机相位与来波相位匹配的概率,同时支持多个波束并行传输,以多波束选择实现更好的多用户分集增益,且机会波束赋形无需反馈完全信道状态信息。因此位置信息辅助的多波束机会波束赋形技术适用于高速铁路通信。
鑒于高速鐵路通信中,列車位置信息可預測、列車車頂中繼轉髮天線數有限,以及反饋信息時延大、多普勒衰落較大、頻繁切換等特性,傳統的波束賦形併不適用于高速鐵路場景。位置信息輔助的多波束機會波束賦形能夠利用列車位置信息可預測的優勢,在機會波束賦形算法中有效地提高髮送波束隨機相位與來波相位匹配的概率,同時支持多箇波束併行傳輸,以多波束選擇實現更好的多用戶分集增益,且機會波束賦形無需反饋完全信道狀態信息。因此位置信息輔助的多波束機會波束賦形技術適用于高速鐵路通信。
감우고속철로통신중,열차위치신식가예측、열차차정중계전발천선수유한,이급반궤신식시연대、다보륵쇠락교대、빈번절환등특성,전통적파속부형병불괄용우고속철로장경。위치신식보조적다파속궤회파속부형능구이용열차위치신식가예측적우세,재궤회파속부형산법중유효지제고발송파속수궤상위여래파상위필배적개솔,동시지지다개파속병행전수,이다파속선택실현경호적다용호분집증익,차궤회파속부형무수반궤완전신도상태신식。인차위치신식보조적다파속궤회파속부형기술괄용우고속철로통신。
In the high-speed railway communication, the position information of train is predictable. However, the number of relaying antennas on the roof is limited, the feedback delay is large, Doppler effect is often serious, handover is frequent, and so on. Therefore, the traditional beamforming is not suitable for high speed railway communications. By taking the advantage of the predictability of the location information of the train, this paper proposes a kind of location information auxiliary multi-beam opportunistic beamforming, which can improve the accuracy of the weighted vector of the beam for the opportunistic beamforming algorithm. The scheme also supports multiple beam parallel transmission, so as to realize better multiuser diversity gain with multi-beam selection. Because opportunistic beamforming needs only some parameters such as SNR in the receiver, the feedback over-head is also reduced. Thus, the scheme proposed in the paper is suitable for high speed railway communications.