| Recently, technology for antenna arrays signal processing has been widely considered due to its strong ability to eliminate spatial interference and to improve the system performance. The incorporation of spectrum spread technology and antenna array is expected to enhance the ability to combat interference, and existing researches mainly focus on the direct-sequence spectrum spread (DS-SS) antenna array system. Multi-carrier spectrum spread (MC-SS) technology has been proven to outperform DS-SS under partial-band interference. Aiming to achieve better performance under jamming, several problems on receiving multi-carrier signal with antenna array have been studied in this dissertation, and the frequency diversity is exploited to construct the relevant receiving algorithms.First, the antenna array receiving for multi-carrier signal in crowded interference environment is studied, and a receiving algorithm is proposed for this condition. In crowded interference, the number of interference saturates the degree of freedom of beamforming, and the response to the desired signal is not guaranteed, and this results in the difficulty for signal detection and decision. The proposed algorithm estimates the direction of arrival (DoA) using the correlation between the desired components in different sub-carrier channels, and then estimates the spatial distribution of interference with spatial spectrum analysis, and forms the weight vector according to maximum signal-to-jamming-and-noise (SJNR) ratio. The proposed algorithm guarantees a unit response to the desired signal, and place nulls of beampattern in the directions of the clusters of interference. Relevant simulations and discussion are also provided to exam the performance of the proposed algorithm.To combat a typical jammer in real world - intermittent jammer, a spatial-domain Least Square (LS) algorithm for receiving multi-carrier signal is proposed. Intermittent jammer is randomly on and off at a particular snapshot, and is usually nonstationary, which makes it difficult for statistics-based beamformer to eliminate interference of this kind. Spatial-domain LS methodology processes data of a single snapshot, and was originally designed for RADAR system. The methodology is developed to apply in communications system in this dissertation, with some new advantages: DoA estimate is not necessary, thus the impact of estimate error is eliminated, moreover, coherent multipath is combined to improve the signal quality. In the proposed algorithm, a filter for one sub-channel uses the output of another filter for another sub-channel as the reference, and the outputs of all the filters converge to the desired signal asymptotically and simultaneously due to the correlated desired component in different sub-channels. Simulations show that proposed algorithm meets the expected performance.Finally, a spatial-temporal constrained minimum output energy (STCMOE) algorithm for multi-carrier signal, spatial-temporal-frequency CMOE (STFCMOE), is proposed, which combines the spatial-temporal (S-T) processing and frequency diversity to provide more degree of freedom for interference suppression. S-T processing employs the spatial directivity and temporal correlation of the desired signal to improve the performance. Constrained minimum output energy (CMOE) methodology minimizes the output energy with the constraint of unit response to the desired signal, which has been proven to have the same performance as training-based MMSE algorithm but only requires the information of spreading code and chip timing for the desired signal, thus CMOE methodology is suitable for blind interference suppression in anti-jamming applications. The proposed algorithm combines the signals from different sub-channels while performing S-T processing. The scheme of noncoherent combining is proposed for generalized multi-carrier system, and the scheme of coherent combining is also given for some specific multi-carrier systems. The simulations present the improvement of the proposed STFCMOE algorithm over STCMOE algorithm, and imply that the proposed STFCMOE algorithm has stronger ability to suppress undesired jamming in much more cases.
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