Seeing that the conventional FFT frequency estimation algorithm for the wide-band under-sampling can only apply to the case of higher input SNR and the single-signal frequency estimation that is used for the precision requirement being not higher, this paper puts forward a method of the joint solution ambiguity of multiple group sampling frequencies, which could implement the unambiguous estimation of multiple signal frequencies under the circumstances of no need to increase the complex paring algorithm. Aimed at the estimation precision of conventional FFT method being lower, a frequency estimation algorithm with graded high resolution is proposed. The estimation precision of this algorithm can be up to the level of 10 kHz, and an order of magnitude is at least improved, with respect to the order of MHz of conventional FFT algorithm. And also the performance analysis is performed on the FFT frequency measurement of single array element, the FFT frequency measurement of synthetic arrays and the high resolution frequency measurement of arrays. Finally, the effectiveness of this proposed method is verified by simulation results.

Most of the existing load-balancing middleware adopt the single object-based load balancing granularity,and pay more attention to the balance among the different replicas of the same object group,which can not meet the demands of the complex data application involved in radar simulation.Therefore,in terms of the technique of common object request broker architecture(CORBA),this paper presents a model of highly scalable load-balancing middleware by using the load balancing granularity based on the portable object adapter(POA) and illustrates numerous key techniques,solutions and their implementations related to the proposed model,including the extensions of load strategy and load metrics,etc.Experimental results show that the proposed model can reduce effectively the average response time and increase the total throughout as well.

为实现野外环境下多通道声阵列远程采集与声场分析,基于USB2.0高速接口,设计实现了单节点最多96个音频信道的同步采集,并基于Wi-Fi无线传输协议802.11n,实现了采集数据的远程无线传输.测试结果表明,本系统的USB2.0高速接口有效数据传输速度最小峰值读/写达到26.5 MBps/22.5 MBps,无线传输速度稳定均值达到106 Mbps.系统除采集卡外,其他设备均采用COTS产品,具有低成本、短研发周期和高可用性的优势.

In this paper,we present and realize a CORBA based high scalable load-balancing middleware model by using per-POA load balancing granularity and the key design challenges including scalable load balancing strategy and load metrics etc.