Wideband digital beamforming (WDBF) technology is a key for the rapidly developing wideband digital array radar (WDAR). In this paper, by comprehensively considering the characteristics of WDAR and the current hardware and software capabilities for radar in engineering, several practical WDBF technologies based on accurate digital true time delay (TTD) are studied. WDBF technology at radio frequency (RF) is applied and tested on a WDAR test-bed. Besides, WDBF technologies at baseband by implementing fractional delay filers at element level and subarray level are presented and simulated.

Knowing the state-of-health (SOH) of equipment, device or component is very essential for the secure and dependable operation of a system. Electrolytic capacitors are undoubtedly one of the essential components of power supply modules used in aerial and underwater vehicles, and every equipment requires a conversion of voltage from one level to another. This has encouraged research into the components of the power supply used in such systems of which electrolytic capacitor is of interest in this study. In this paper, we explore a new approach to implementing prognostics and health management (PHM) for electrolytic capacitors and propose a method of estimating the SOH leading to the prediction of the remaining useful life (RUL). This is accomplished by using a bidirectional long short-term memory (BLSTM) network to capture the degradation trends. We demonstrate the power and leverage that this method brings to bear in encoding time-domain dependencies in accurately estimating the SOH bereft of state models as employed in traditional methods. We validate the proposed approach using capacitor data recorded at different electrical over-stress accelerated aging conditions. The proposed method surpasses other existing methods in RUL prediction as indicated by the error and relative accuracy.

An airborne phased-multiple-input-multiple-output (Phased-MIMO) radar with collocated antenna array is a tradeoff of phased array radar and MIMO radar. Its transmitting array is divided into multiple subarrays that are allowed to be overlapped. In this letter, we mainly study the array partitioning scheme of the airborne Phased-MIMO radar with equal uniform linear subarrays that are fully overlapped on the basis of space-time adaptive processing (STAP). A mathematical formula is derived to determine the number of subarrays and the elements in each subarray according to the principle of maximum STAP signal-to-interference-plus-noise ratio (SINR). The SINR performances corresponding to different partitioning schemes are simulated and discussed to demonstrate the effectiveness of the proposed mathematical formula for array partitioning in the sense of maximum STAP SINR.