Planar end-fire arrays can be used in airborne radar applications for forward and rear vision. The purpose of this work is to demonstrate the viability of constructing end-fire arrays with good bandwidth and front-to-back (f/b) ratio. The array so constructed must be extendable to a large number (possibly >1 000) of elements depending on the platform. In this work, starting from a basic S-band 2×2 array, arrays with higher number of elements have been studied through simulations such as 4×4, 4×8, and 2×16 configurations. An end-fire array comprising 4×8 elements (uniformly excited) has been successfully fabricated and tested giving a f/b ratio of 15 dB, and directivity 15 dB and an array comprising 4×8 elements excited by coefficients of Chebyshev polynomials has been simulated which gives a f/b ratio of 25 dB and similar directivity. Beam steering simulations show that the 4×8 array can be steered to ±25 degrees with acceptable side lobe levels.

This paper presents the design of a source injection parallel coupled (SIPC) quadrature voltage-controlled oscillator (QVCO), realized with pMOS transistors, relaxing the sensitivity to substrate-induced noise and flicker noise, 1 f effect. A stacked planar spiral inductor exhibiting a Q factor of 5.8, with a pMOS-based varactor of 32% tuning range is implemented in 0.18 mm CMOS technology. The phase noise of the SIPC QVCO architecture simulated at 1 MHz of offset frequency is observed to be -111.43 dBc/Hz, in comparison with the phase noise of a conventional QVCO architecture which is observed to be -106.15 dBc/Hz, while dissipating the same amount of power about 14.6 mW. The effect of coupling factor, K to the amplitude and phase noise degradation is also investigated and verified.

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The advances in unmanned aerial vehicles (UAV) and their applications in various areas of military, communications made the researchers focus on the design of compact, wide beam, lightweight antennas. In this article, a novel miniaturized printed dipole antenna with quasi rhombus shape exhibiting an Impedance bandwidth of 113% (within 2:1 VSWR for the frequency range from 6.3 to 23 GHz) is presented. The length and width of the antenna element in terms of λ6.5 considered at the resonant frequency of 6.5 GHz is 0.347λ6.5 × 0.369λ6.5 (16 mm × 17 mm). Design equations are included to carefully match the impedance at every segment of the antenna. The optimized element is fabricated to confirm the finding from the analysis. The wideband characteristics of the antenna with good cross‐polarization levels, stable radiation patterns and matching performance of element makes it suitable for various EW applications in UAV systems. The optimized linear antenna array with eight elements is fabricated and tested to evaluate its suitability for broadband applications. Various antenna parameters such as reflection coefficients, bandwidth, radiation patterns are measured and compared with computed results to validate its suitability for EW applications. Miniaturization of antenna size finds the suitability of antenna to be used for smaller platforms having smaller surface similar to UAV. The wideband performance from a single antenna/array is useful for multitude applications. Some of the areas of application are shared aperture; communication support measure; SATCOM; data link; electronic support measure; radar warning receiver applications.