The LHCD antenna that will be used in HL-2A is the original one used in HL-1M,which will be modified. We measured the feature of the antenna. The features include the reflection of main waveguide, VSWR, the adjacent p...The LHCD antenna that will be used in HL-2A is the original one used in HL-1M,which will be modified. We measured the feature of the antenna. The features include the reflection of main waveguide, VSWR, the adjacent phrasing between the sub-waveguides and so on. The paper describes the measured results and spectrum calculation based on the measured parameters. From the works we can appreciate our antenna correctly which will be useful for LHCD experiment on HL-2Ain the year.展开更多
In this paper, we propose the blind space-time high rate multi-user detector for synchronous uplink multi-rate Direct Sequence Code Division Multiple Access （DS-CDMA） systems with antenna array at the base station. ...In this paper, we propose the blind space-time high rate multi-user detector for synchronous uplink multi-rate Direct Sequence Code Division Multiple Access （DS-CDMA） systems with antenna array at the base station. By employing antenna array at the base stations, the spatial dimension is used efficiently to suppress co-channel interference and increase the capacity for multi-rate CDMA system. After low rate physical users in the system are modeled as corresponding high rate virtual users, we construct the space-time signature vectors of virtual users. And subspace projection algorithm is employed to estimate space-time signature vectors blindly. Then a soft-decision high rate lnultiuser detector is proposed based on the estimated signature vectors, which avoids estimating the ambiguous complex factors which are necessary in traditional blind detector. Numerical simulation results evaluate the performance in terms of Bit Error Rate （BER） for the proposed scheme. Simultaneously, it demonstrates that the system capability increases two times when using twoelement antenna array.展开更多
文摘The LHCD antenna that will be used in HL-2A is the original one used in HL-1M,which will be modified. We measured the feature of the antenna. The features include the reflection of main waveguide, VSWR, the adjacent phrasing between the sub-waveguides and so on. The paper describes the measured results and spectrum calculation based on the measured parameters. From the works we can appreciate our antenna correctly which will be useful for LHCD experiment on HL-2Ain the year.
基金Partially supported by the National Natural Science Foundation of China (No.60572046 & No.60502022) and the Research Fund for Doctoral Program of Higher Education of China (No.20020698024 & No.20030698027).
文摘In this paper, we propose the blind space-time high rate multi-user detector for synchronous uplink multi-rate Direct Sequence Code Division Multiple Access （DS-CDMA） systems with antenna array at the base station. By employing antenna array at the base stations, the spatial dimension is used efficiently to suppress co-channel interference and increase the capacity for multi-rate CDMA system. After low rate physical users in the system are modeled as corresponding high rate virtual users, we construct the space-time signature vectors of virtual users. And subspace projection algorithm is employed to estimate space-time signature vectors blindly. Then a soft-decision high rate lnultiuser detector is proposed based on the estimated signature vectors, which avoids estimating the ambiguous complex factors which are necessary in traditional blind detector. Numerical simulation results evaluate the performance in terms of Bit Error Rate （BER） for the proposed scheme. Simultaneously, it demonstrates that the system capability increases two times when using twoelement antenna array.
