Joint CFO and DOA estimation for multiuser OFDMA uplink
نویسندگان
چکیده
In this article, we develop a new subspace-based multiuser joint carrier frequency offset (CFO) and direction-ofarrival (DOA) estimation scheme for orthogonal frequency division multiple access uplink transmissions. We leverage multi-antenna at the receiver and consider that the signals transmitted by each user arrive at the receiving antenna array from multiple DOAs after bouncing from both surrounding and far scatterers. The rank reduction approach is then exploited to estimate the multiple CFOs and DOAs. Specifically, for each user, after the CFO estimation from one-dimensional search, its multiple DOAs can be obtained simultaneously via polynomial rooting. The proposed method supports generalized subcarrier assignment scheme and fully loaded transmissions. Both performance analysis and numerical results are provided to corroborate the proposed studies.
منابع مشابه
Frequency synchronization for carrier allocation in uplink OFDMA systems
Since OFDMA is extremely sensitive to frequency offsets, one of the most prominent issues in the design and implementation of OFDMA based systems is the need for a very fine frequency synchronization. The task of frequency synchronization becomes even more challenging in the uplink OFDMA based systems where one transmission symbol is generated by the contribution of different users. Our goals i...
متن کاملA reduced complexity scheme for carrier frequency synchronization in uplink 802.16e OFDMA
Synchronization of the carrier frequency offset (CFO) in the uplink of OFDMA systems is a complex task because each user presents a different CFO. It is performed in two stages: estimation and compensation. Although a few existing schemes already achieve good performance in terms of bit error rate (BER), all of them perform huge amounts of operations, specially during estimation, thus leading t...
متن کاملNovel Blind CFO Estimator for Uplink Interleaved OFDMA Systems
Abstract In orthogonal frequency-division multiple access (OFDMA) systems, closely spaced and overlapped sub-carriers are divided into groups and assigned to multiple users for simultaneous transmission. However, carrier frequency offsets (CFOs) between the transmitter and the receiver destroy the orthogonality and introduce inter-carrier interference (ICI), resulting in multiple-access interfe...
متن کاملPSO and ABC based Novel Carrier Frequency Offset Estimation Techniques for Wi-MAX Uplink Transmissions
Carrier frequency offset (CFO) estimation is a challenging task in Wi-MAX uplink as it uses orthogonal frequency division multiple access (OFDMA) which demands extremely accurate frequency synchronization. In OFDMA uplink, each user may experience a different CFO relative to the base station reference carrier and the estimation of them turn out to be a multiple parameter estimation problem. In ...
متن کاملGravitational Search Algorithm for Low Complexity Carrier Frequency Offset Estimation in Uplink OFDMA Systems
Orthogonal frequency division multiple access (OFDMA) systems in the uplink suffer from multiple access interference (MAI) due to their high sensitivity to frequency misalignments between different users. Moreover, carrier frequency offset (CFO) is a major factor that degrades performance of the OFDMA system. As the maximumlikelihood (ML) estimator is impractical in this context, we introduce a...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- EURASIP J. Adv. Sig. Proc.
دوره 2012 شماره
صفحات -
تاریخ انتشار 2012