Design and compensation of second-order sub-sampling digital frontend  

作　　者：王洪梅 KIM Jae-hyung LEE Sang-hyuk KIM Hyung-jung KIM Jin-up KOH Jong-seog 

机构地区：[1]School of Mechatronics, Changwon National University [2]Electrical and Electronic Engineering, Xi'an Jiaotong-Liverpool University [3]Smart Radio Team, Electonics and Telecommunication Research Institute [4]Korea Telecommunication Company

出　　处：《Journal of Central South University》2012年第2期408-416,共9页中南大学学报（英文版）

基　　金：Research financially supported by Changwon National University in 2009-2010;the Second Stage of Brain Korea 21 Projects

摘　　要：The problem of designing a digital frontend (DFE) was considered which can dynamically access or sense dual bands in any radio frequency (RF) regions without requiring hardware changes. In particular, second-order bandpass sampling (BPS) as a technique that enables to realize the multiband reception function was discussed. In a second-order BPS system, digital reconstruction filters were utilized to eliminate the interferences generated while down converting arbitrarily positioned RF-band signals by using the direct digitization method. However, the inaccuracy in the phase shift or the amplitude mismatch between the two sample streams may cause insufficient rejection of interference. Practical problems were studied, such as performance degradation in signal-to-interference ratio (SIR) and compensation methods to overcome them. In order to demonstrate the second- order BPS as a flexible DFE suitable for software-defined radio (SDR) or cognitive radio (CR), a DFE testbed with a reconfigurable structure was implemented. Moreover, with a view to further demonstrate the proposed compensation algorithms, experimental results show that dual bands are received simultaneously.The problem of designing a digital frontend （DFE） was considered which can dynamically access or sense dual bands in any radio frequency （RF） regions without requiring hardware changes. In particular, second-order bandpass sampling （BPS） as a technique that enables to realize the multiband reception function was discussed. In a second-order BPS system, digital reconstruction filters were utilized to eliminate the interferences generated while down converting arbitrarily positioned RF-band signals by using the direct digitization method. However, the inaccuracy in the phase shift or the amplitude mismatch between the two sample streams may cause insufficient rejection of interference. Practical problems were studied, such as performance degradation in signal-to-interference ratio （SIR） and compensation methods to overcome them. In order to demonstrate the second- order BPS as a flexible DFE suitable for software-defined radio （SDR） or cognitive radio （CR）, a DFE testbed with a reconfigurable structure was implemented. Moreover, with a view to further demonstrate the proposed compensation algorithms, experimental results show that dual bands are received simultaneously.

关 键 词：bandpass sampling second order band-pass sampling RECONFIGURATION software-defined radio 

分 类 号：TN925[电子电信—通信与信息系统] TN713[电子电信—信息与通信工程]