An extreamly large scale periodic array antenna is required for the power transmission in the space solar power systems. Analysis of the array antenna is important to estimate radiation property of the array antenna, but a full-wave analysis requires too much computer memory and too long CPU time. In order to overcome this difficulty, the impedance extension method is proposed as a method of ap...

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 ...

This paper introduces a base station antenna system as a future cellular technology. The base station antenna system is the key to achieving high-speed data transmission. It is particularly important to improve the frequency reuse factor as one of the roles of a base station. Furthermore, in order to solve the interference problem due to the same frequency being used by the macro cell and the s...

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 ...