This paper shows that an optimal antenna pattern for active phased array synthetic aperture radar (SAR) has been synthesized to meet the best performances based on particle swarm optimization (PSO) and adaptively selected weighting factors. Because the antenna radiation pattern has a very close relation with the performance of an active phased array SAR system, the authors derived the multi-obj...

This paper represents a new active phase array antenna for Ku-band mobile service that will be possible in satellite broadcasting service. The main idea for the antenna is to use minimum active array element with cost-effective one-dimensional subarrays with inclined pencil beam structure for 34 dBi gain. For this antenna, we also used the squint beam tracking algorithm. This tracking gives dif...

1. Introduction A direct broadcasting satellite(DBS) service via Koreasat 3 is currently provided and there are many subscribes for a residential house. In addition, many people want to watch the DBS TV even at vehicles because it has advantages over terrestrial TV broadcasting with high quality, simultaneity, wide coverage, and so on. Several antenna systems for mobile DBS reception have been ...

This dissertation focuses on the implementation of integrating pulse transmitter with wide-band antenna array into a chip by CMOS process for beam-forming in millimeter-wave (mm-wave) active imaging applications. Integrated antenna arrays in this research electrically control and steer radiated-pulse beams towards objects to be imaged. Among imaging approaches, active imaging method provides mo...

Antennas integrated with active circuitry are usually referred to as active antenna arrays. The integration can be done at different levels, depending on the goal and application. For example, a low-noise amplifier (LNA) is often integrated directly with the antenna for reduced loss and therefore decreased noise figure. Another example is the integration of power amplifiers with antenna arrays ...

Electronic beam steering capability of phased array antenna systems offer significant advantages when used in real aperture imaging radiometers. The sensitivity of such systems is limited by the ability to accurately calibrate variations in the antenna circuit characteristics. Passive antenna systems, which require mechanical rotation to scan the beam, have stable characteristics and the noise ...

The impedance extension method (IEM) has been proposed so far, as a method for analysis of a huge-scale periodic array antenna for power transmission from space solar power systems (SSPS) to the earth[1][2]. Since the IEM is an approximate method based on active impedance properties of elements in the periodic array antenna[3], the IEM can only be applied to the periodic array antenna. However,...