Analysis of the uplink of an asynchronous multi-user DMT OFDMA system impaired by time offsets, frequency offsets, and multi-path fading

Tonello, Andrea M.; Laurenti, Nicola; Pupolin, S.

doi:10.1109/vetecf.2000.886275

Cited by 96 publications

(63 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In such a case the system is a multiuser extension of filtered multitone modulation (FMT) [12], and we refer to it as filtered multitone multiple access (FMT-MA) [35,42,43]. When the sub-channel transmit filters have a rectangular impulse response, the system is referred to as discrete multitone multiple access (DMT-MA) [39][40][41]. In literature, DMT-MA is also referred to as multiuser orthogonal frequency division multiplexing (OFDM).…”

Section: Introductionmentioning

confidence: 99%

Asynchronous multicarrier multiple access: Optimal and sub-optimal detection and decoding

Tonello¹

2003

Bell Labs Tech. J.

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Asynchronous multicarrier multiple access: Optimal and sub-optimal detection and decoding

Tonello¹

2003

Bell Labs Tech. J.

View full text Add to dashboard Cite

“…Multiplexing is obtained by allocating a subset of the available N tones to each user. A number of tone allocation methods are possible [5], [6], [9]. For instance, the spectrum can be partitioned into a number of blocks of carriers.…”

Section: B Media Access Protocolmentioning

confidence: 99%

“…Further, apply appropriate tone allocation strategies in conjunction with time and frequency guards, e.g., DMT with cyclic prefix, [5]- [6].…”

Section: Simplified Multiuser-carrier Detectionmentioning

confidence: 99%

“…For instance, the prototype filter can be a squared-root-raised-cosine filter, or a Gaussian shaped filter. The system is referred to as a discrete multitone multiple access (DMT-MA), or also multiuser OFDM, when the prototype filter is a rectangular time-window [5]. An overview of FMT modulation for application in broadband digital subscriber lines can be found in [2].…”

Section: Introductionmentioning

confidence: 99%

“…Some investigation of the effect of the time offsets in a DMT system with sub-optimal single user detection was done in [3]. A unified study of the joint effect of time offsets, frequency offsets, and multi-path fading in a DMT-MA system with single user detection was done in [5] based on which capacity evaluations were carried out in [6]. The performance of suboptimum single user detection in more general MTMA architectures was presented in [10].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Multiuser detection and turbo multiuser decoding for asynchronous multitone multiple access systems

Tonello¹

Proceedings IEEE 56th Vehicular Technology Conference

Self Cite

View full text Add to dashboard Cite

-We consider multicarrier multiple access architectures that are based on combining discrete multitone (DMT) or filtered multitone (FMT) modulation with multiplexing of tones across users. Communications are asynchronous, e.g., uplink cellular communications. Optimum multiuser detection is formulated for demodulation of multitone signals that experience time and frequency asynchronism and propagate through frequency selective fading channels. Channel coding is also considered and practical decoding based on iterative (turbo) multiuser detection and decoding is investigated. Simplified detection schemes are also devised.

show abstract

A hybrid joint ML technique for CFO, timing offset, and channel estimations in an OFDMA uplink

Ijyas

Sameer

2012

Int J Communication

View full text Add to dashboard Cite

In this paper, we propose a novel hybrid joint maximum-likelihood estimator for carrier frequency offset (CFO), timing offset, and channel response of all users in the uplink of an orthogonal frequency division multiple access (OFDMA) system. The proposed estimation method significantly reduces complexity of this multiparameter, multidimensional optimization problem, using the concept of separation of the different user signals by means of newly defined projection operators. This projection technique is combined with the alternating projection method available in the literature to arrive at a new hybrid algorithm that offers significant performance advantages in terms of computational complexity and estimator performance. The joint estimation of the CFOs, timing offsets, and channel coefficients for all active users together at the base station of the OFDMA uplink is a rarely addressed task. The proposed method also offers the flexibility of application to any subcarrier assignment scheme used in OFDMA systems. Extensive simulation studies corroborate the advantages of the new hybrid method for all three estimation requirements in the multiuser OFDMA uplink. in 1998 and he is presently working as an Assistant Professor there. He has published papers in several international conferences and journals, and holds four patent applications. Sameer S. M. is a member of IEEE and a regular reviewer of many reputed international conferences and journals. He has served on the Technical Programmes and other Committees of several International Conferences. His research interests include synchronization and channel estimation techniques for multicarrier communication systems, Wi-MAX system design challenges, optimization techniques for wireless communication, cognitive radio, and physical layer issues in cooperative communication systems.

show abstract

Analysis of the uplink of an asynchronous multi-user DMT OFDMA system impaired by time offsets, frequency offsets, and multi-path fading

Abstract: We study through analysis the joint effect of time offsets, frequency offsets, and multi-path

Cited by 96 publications

References 5 publications

Asynchronous multicarrier multiple access: Optimal and sub-optimal detection and decoding

Asynchronous multicarrier multiple access: Optimal and sub-optimal detection and decoding

Multiuser detection and turbo multiuser decoding for asynchronous multitone multiple access systems

A hybrid joint ML technique for CFO, timing offset, and channel estimations in an OFDMA uplink

Contact Info

Product

Resources

About