calibration of phased array of reflector antennas using leo satellites

Phased Array Feeds for Low Noise Reflector Antennas

Phased array feeds offer the possibility of more efficient use of large radio astronomy reflector antennas by providing more closely spaced beams over a wide field of view and higher aperture efficiency in each beam than have been realized with horn feeds. Phased arrays have been used extensively in rapid scanning radars and shaped-beam satellite systems, but the array design criteria for low-n...

Beam Patterns of Low Frequency Radio Antennas using LEO Satellites

Phased array antenna using MEMS phase shifter

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 ...

Optical beam forming for phased-array antennas

communications spectrum from copper cables, optical fibres, microwaves, radio and electromagnetic compatibility. Our research concentrates on optical signal processing and networks, mobile communications, microwave techniques and radiation from ICs and PCBs [1]. A considerable (and particularly interesting) part of it is related to optical beam forming for phased array antennas, using optical r...

Phased array antennas for mobile communications

Mobile communications demands present new challenges for transmission. Traditionally, antennas used at base stations to communicate with mobile units within an area are omni-directional. In order to allow a higher density of participants within the area, a “pencil” beam is used. The beam tracks and follows the movement of the mobile unit. This results in an additional advantage: the fading effe...

Efficient Calibration of Active-Phased-Array SARs

Calibration of the first space-borne SAR instruments, with only one swath and based on passive antenna technologies, (e.g. ERS-1) required the in-flight characterisation of that single-swath instrument over well-known scatterers (reflectors, transponders and rainforest sensing data). Modern systems evolved to more access flexibility -therefore, multiple beams-, and multi-polarisation that led t...