The original paper is in English. Non-English content has been machine-translated and may contain typographical errors or mistranslations. ex. Some numerals are expressed as "XNUMX".
Copyrights notice
The original paper is in English. Non-English content has been machine-translated and may contain typographical errors or mistranslations. Copyrights notice
Untuk sistem tatasusunan antena stesen pangkalan dengan mod pembahagian masa-dupleks (TDD), tindak balas saluran pautan bawah adalah sama dengan tindak balas saluran pautan atas jika masa penduaan adalah kecil, oleh itu selalunya dipercayai bahawa mod TDD memudahkan masalah pembentukan rasuk pautan bawah kerana pemberat pautan atas boleh memohon pautan ke bawah secara langsung. Dalam surat ini, kami menunjukkan bahawa untuk sistem TDD DS-CDMA, walaupun respons saluran pautan atas dan pautan bawah adalah sama, wajaran pautan atas optimum tidak lagi sama dengan pautan bawah optimum disebabkan oleh sifat tak segerak dalam pautan atas dan sifat segerak dalam pautan bawah, serta sebagai trafik kadar data yang berbeza dan keperluan QoS. Simulasi komputer menunjukkan bahawa untuk trafik asimetri, jika pemberat pautan atas digunakan untuk pautan ke bawah secara langsung, kapasiti sistem pautan bawah adalah kurang daripada 50% daripadanya dengan pemberat pautan ke bawah yang optimum.
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Salinan
Ying-Chang LIANG, "Can Uplink Weights be Used for Downlink in TDD DS-CDMA Systems with Base Station Antenna Array?" in IEICE TRANSACTIONS on Communications,
vol. E85-B, no. 8, pp. 1627-1630, August 2002, doi: .
Abstract: For base station antenna array systems with time-division-duplex (TDD) mode, downlink channel responses are equal to uplink channel responses if the duplexing time is small, thus it is often believed that TDD mode simplies downlink beamforming problem as uplink weights can be applied for downlink directly. In this letter, we show that for TDD DS-CDMA systems, even though uplink and downlink channel responses are equal, optimal uplink weights are no longer equal to the optimal downlink ones due to asynchronous property in uplink and synchronous property in downlink, as well as different data rate traffic and QoS requirements. Computer simulations show that for asymmetric traffic, if uplink weights are used for downlink directly, downlink system capacity is less than 50% of that with optimal downlink weights.
URL: https://global.ieice.org/en_transactions/communications/10.1587/e85-b_8_1627/_p
Salinan
@ARTICLE{e85-b_8_1627,
author={Ying-Chang LIANG, },
journal={IEICE TRANSACTIONS on Communications},
title={Can Uplink Weights be Used for Downlink in TDD DS-CDMA Systems with Base Station Antenna Array?},
year={2002},
volume={E85-B},
number={8},
pages={1627-1630},
abstract={For base station antenna array systems with time-division-duplex (TDD) mode, downlink channel responses are equal to uplink channel responses if the duplexing time is small, thus it is often believed that TDD mode simplies downlink beamforming problem as uplink weights can be applied for downlink directly. In this letter, we show that for TDD DS-CDMA systems, even though uplink and downlink channel responses are equal, optimal uplink weights are no longer equal to the optimal downlink ones due to asynchronous property in uplink and synchronous property in downlink, as well as different data rate traffic and QoS requirements. Computer simulations show that for asymmetric traffic, if uplink weights are used for downlink directly, downlink system capacity is less than 50% of that with optimal downlink weights.},
keywords={},
doi={},
ISSN={},
month={August},}
Salinan
TY - JOUR
TI - Can Uplink Weights be Used for Downlink in TDD DS-CDMA Systems with Base Station Antenna Array?
T2 - IEICE TRANSACTIONS on Communications
SP - 1627
EP - 1630
AU - Ying-Chang LIANG
PY - 2002
DO -
JO - IEICE TRANSACTIONS on Communications
SN -
VL - E85-B
IS - 8
JA - IEICE TRANSACTIONS on Communications
Y1 - August 2002
AB - For base station antenna array systems with time-division-duplex (TDD) mode, downlink channel responses are equal to uplink channel responses if the duplexing time is small, thus it is often believed that TDD mode simplies downlink beamforming problem as uplink weights can be applied for downlink directly. In this letter, we show that for TDD DS-CDMA systems, even though uplink and downlink channel responses are equal, optimal uplink weights are no longer equal to the optimal downlink ones due to asynchronous property in uplink and synchronous property in downlink, as well as different data rate traffic and QoS requirements. Computer simulations show that for asymmetric traffic, if uplink weights are used for downlink directly, downlink system capacity is less than 50% of that with optimal downlink weights.
ER -