| 1. |
- Edfors, Ove, et al.
(författare)
-
An introduction to orthogonal frequency-division multiplexing
- 1997
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report is an introduction to orthogonal frequency-division multiplexing (OFDM). The focus is on signal processing areas pursued by our research group at Luleå University of Technology. We present an historical background and some frequently used system models. Typical areas of applications are also described, both wireless and wired. In addition to the general overview, the addressed areas include synchronization, channel estimation and channel coding. Both time and frequency synchronization are described, and the effects of synchronization errors are presented. Different types of channel estimators are described, where the focus is on low-complexity algorithms, and in this context, advantages and disadvantages of coherent and differential modulation are also discussed. Channel coding is described, both for wireless and wired systems, and pointers are included to evaluation tools and bitloading algorithms. An extensive bibliography is also included.
|
|
| 2. |
- Landström, Daniel, et al.
(författare)
-
Time and frequency offset estimation in OFDM systems employing pulse shaping
- 1997
-
Ingår i: Bridging the way to the 21st century. - Piscataway, NJ : IEEE Communications Society. - 0780337778 ; , s. 279-283, s. 279-283
-
Konferensbidrag (refereegranskat)abstract
- Time and frequency offset estimation is addressed in an OFDM system that uses a cyclic prefix and pulse shaping. Earlier work has presented a method that avoids the use of pilots by exploiting the inherent correlation in the cyclically extended OFDM symbol. In this paper this technique is extended to include systems with pulse shaping. The joint Maximum Likelihood estimator of time and frequency offsets for such systems is presented and evaluated. An implementable structure of the extended estimator is given. Simulations show that it is possible to maintain the performance when introducing pulse shaping into an OFDM system.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- van de Beek, Jaap, et al.
(författare)
-
On synchronization in an OFDM based UMTS proposal
- 1997
-
Ingår i: Emerging techniques for communication terminals. - Toulouse : INP-ENSEEIHT. ; , s. 315-320
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In this paper we discuss three signal models and respective Maximum Likelihood estimators of time and frequency osets. We consider implementation structures for these estimators. Furthermore, we discuss the applicability of these estimators and some variants in a proposal for the future UMTS.
|
|
| 7. |
- Wahlqvist, Mattias, et al.
(författare)
-
Description of Telias OFDM based proposal
- 1997
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This document gives an overview of Telias OFDM based proposal for UTRA and should be cinsidered as an input to the OFDM concept group within SMG 2. The document describes the fundamental frame structure, principles of the detection, modulation, coding and synchronization. Further, the channel structure, the resource management and handover principles are outlined
|
|
