This article presents a versatile pattern synthesis algorithm for controlling the sidelobe level and nulling region for circular antenna arrays. Nonuniform fast Fourier transform using the min–max interpolation method is utilized to overcome the nonlinear feature of circular arrays. The major advantage of the proposed algorithm is low complexity, which is key for hardware implementation. Moreover, the proposed algorithm functions well in amplitude‐only pattern synthesis, which may be required for low‐cost array systems using attenuators instead of complete amplitude and phase adjustment modules. Additionally, element failure of antenna arrays can be minimized in practical operations by resynthesizing the pattern by using the remaining antennas to achieve satisfactory performance. Simulation results indicate the lower complexity and higher versatility of the proposed algorithm compared with the conventional methods.

The robust three-dimensional position architecture is proposed in the paper, where the hybrid time difference of arrival (TDOA) and direction of arrival (DOA) position system was designed to backup the four-station TDOA position system. The digital time delay estimation (TDE) receiver is used for TDOA measurement and the cylindrical array antenna is used for DOA measurement. The general formula of linear phase compensation for cylindrical array antenna in horizontal plane is derived. The detection probability of the TDE receiver and the circular error probability (CEP) of the position systems over Rayleigh fading channel were numerically computed in three-dimensional space. Simulations indicate that the position accuracy of the four-station TDOA position system is degraded but the location function can be retained by the hybrid TDOA and DOA position system when any one of four-stations is out of work.

Of the 20 biotype 1 Gardnerella vaginalis isolates analyzed, 10 from patients with bacterial vaginosis and 10 from patients without bacterial vaginosis, none shared the same DNA fingerprint. However, a 1.18-kb HindIII fragment was common among 18 of the 20 biotype 1 isolates in a restriction fragment length polymorphism analysis with a 7.9-kb G. vaginalis DNA probe.

 Based on software-defined radio (SDR) architecture, a multiple-null digital beam former (DBF) that can adjust the number, width and depth of the nulls in accordance with the environment requirements is realized using the field programmable gate array (FPGA) to improve the interference cancellation capability of the two-dimensional array antennas. The hardware reconfiguration feature of SDR architecture can support multiple modes of the DBF striving for compactness and efficient processing power. The Howells-Applebaum algorithm, eigen value decomposition (EVD) and principal component methods are employed to derive the optimal weighting matrix of the multiple-null DBF and simplify the computation of inverse interference covariance matrix, which can be implemented with the parallel processing architecture. If there is no jamming occurred, the DBF returns to its normal beam pattern. Finally, the simulations demonstrate the robustness of the interference cancellation of the multiple-null DBF for a 16 by 16 phase array antenna.Keywords  software-defined radio (SDR), digital beam former (DBF), interference covariance matrix, multiple-null, eigen value decomposition (EVD), FPGA.