Distribution of phase end delay in corporate-fed phased arrays is examined. RMS phase errors versus scan angle are shown for digital phasers. Phaser bits should all b e located a t each element. Delayer bits can b e also, but delayer loss, dispersion, temperature sensitivity, and size mitigate against using so many delayers. Alternative topologies, where delay bits are distributed in the corpor...

We report on microwave signal-mixing functionality for a fiber-based optoelectronic oscillator. Two wavelength division multiplexed (WDM) channels carrying RF signals at 1320 and 1312 nm are simultaneously upconverted/downconverted by the fiber-based optoelectronic oscillator. The conversion efficiency is found to be approximately −8 dB, and the incoming signals have no effects on the local osc...

Modern microwave and millimeter wave phased array antennas are attractive because of their ability to steer wave beams in space without physically moving the antenna element. A typical phased array antenna may have several thousand elements fed by a phase shifter for every antenna, which can steer the resulting array beam to different directions. Their low loss, low cost and lightweight phase s...

This article presents a phased array antenna employing MEMS phase shifter. The proposed phased array antenna consists of eight square patch antennas operating at 10.4 GHz with a bandwidth of 400 MHz. Feed line for each patch passes through a MEMS phase shifter realized by a series of bridges above the transmission line. The distance between the bridge and the transmission line underneath it is ...

Abstract A low sidelobe 77 GHz centre‐fed microstrip patch array antenna is proposed for automotive radar application. The comprises eight linear arrays, each of which by a coplanar waveguide with ground transmission line at the back patches. Each contains 10 units, are connected through T‐type power divider network to achieve −30 dB Taylor weighted distribution. simulation results show that de...

To lower costs and reduce latency, a network of adaptive array ground stations, distributed across the United States, is considered for the downlink of a polar-orbiting low earth orbiting (LEO) satellite. Assuming the X-band 105 Mbps transmitter of NASA's Earth Observing 1 (EO-1) satellite with a simple line-of-sight propagation model, the average daily download capacity in bits for a network o...