Verification of Compensation Effect of Quasi- Inverse Filter in Wideband Communication System
نویسنده
چکیده
In recent years, the demands on a large capacity, high-reliability and high quality are remarkable in the wireless communication system. UWB (Ultra Wide Band) wireless communications can transmit at a speed of several gigabits per second [1]. A wideband antenna is required for the system because a very wide frequency band is utilized in UWB. However, it is difficult to obtain an antenna that has uniform characteristics in all UWB frequency bands. Pre-distortion technology to compensate for the distortion due to the antenna characteristics before transmission was proposed in [2]. To compensate for the distortion in the gain characteristics of the antenna, a method of inverse filtering was proposed [3] [4]. However, the compensation effect of the inverse filter was not sufficient when the distortion of the antenna gain characteristics was severe. The authors have proposed a quasi-inverse filter (QIF) in order to improve the compensation effect and an effectiveness of the proposed filter has been indicated through computer simulation [5]. In the simulation, a simple model for antenna characteristics was employed, however, real antenna characteristics are very complex in general. In this paper, the QIF is applied to two antennas as a concrete example of a broadband antenna; one is a disc monopole antenna, and the other is a square loop antenna.
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Compensation Effect of Quasi-Inverse Filter (QIF) on Frequency Characteristic Distortion in Wideband Systems
High-speed wireless communication systems have attracted much attention in recent years. To achieve a high-speed wireless communication system that utilizes an ultra-wide-frequency band, a broadband antenna is required. However, it is difficult to obtain an antenna that has uniform characteristics in a broad frequency band. Moreover, propagation characteristics are distorted in a multi-path env...
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