Results 251 to 260 of about 5,925,887 (294)

Carrier phase recovery for turbo-coded linear modulations

2002 IEEE International Conference on Communications. Conference Proceedings. ICC 2002 (Cat. No.02CH37333), 2003
In this paper, we present a low-complexity carrier phase estimation algorithm suited for turbo-coded 16-QAM modems. The estimator is based on a maximum likelihood (ML) approach, and unlike previously published work, makes iterative use of soft decisions provided by the soft-in soft-out decoders within the overall iterative turbo decoding scheme ...
LOTTICI, VINCENZO, LUISE, MARCO
openaire   +2 more sources

A Fine Carrier Phase Recovery Method for 32APSK

2018
When 32-ary amplitude phase shift keying (32APSK) modulation is used in the communication system, carrier recovery is one of the most important technology. The decision-directed (DD) phase locked loop (PLL) is widely used for carrier recovery. Based on the decision-directed (DD) phase locked loop (PLL) algorithm, the paper proposes a new fine carrier ...
Yulei Nie, Zijian Zhang 0001, Peipei Liu
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Soft carrier phase recovery for continuous phase modulations

2010 European Wireless Conference (EW), 2010
In this paper a general soft-based synchronization technique for continuous phase modulations (CPM) is presented. In particular two soft carrier phase estimation algorithms are derived, being the phase the parameter that shows the lower implementation complexity.
Marilena Maiolo, Gabriele Boccolini, Marco Luise   +2 more
openaire   +1 more source

ML NDA carrier phase recovery for OFDM systems

1999 IEEE International Conference on Communications (Cat. No. 99CH36311), 2003
A maximum likelihood (ML) estimation algorithm is derived for carrier synchronization in OFDM systems with MPSK modulation. The algorithm derived is nondecision-aided (NDA) and maximizes the low SNR limit of the likelihood function averaged over the MPSK signal constellation.
Ayesha T. Huq, Erdal Panayirci, Costas N. Georghiades   +2 more
openaire   +2 more sources

Carrier Phase Recovery with CPM Modulations

1997
In this chapter we consider carrier phase recovery for CPM signaling. By and large the presentation follows the same route taken with linear modulations. In particular, data-aided (DA) estimation is considered first, then we concentrate on decision-directed (DD) methods and, finally, on non-data-aided (NDA) techniques (either clock-aided or non-clock ...
Umberto Mengali, Aldo N. D’Andrea
openaire   +1 more source

An EM approach to carrier phase recovery in AWGN channel

ICC 2001. IEEE International Conference on Communications. Conference Record (Cat. No.01CH37240), 2002
In this paper, the problem of carrier phase recovery of linearly modulated signals in the presence of unknown data symbols is studied within the expectation-maximization (EM) framework using two different approaches. First, an iterative joint maximum likelihood (ML) phase estimator and data detector is derived using conditional maximization steps ...
Pasupathy, S., Mämmelä, Aarne, Nissilä, Mauri   +3 more
openaire   +1 more source

Carrier Phase Recovery with Linear Modulations

1997
In this chapter we investigate algorithms for carrier phase estimation with linear modulations. As with frequency recovery, ML estimation methods will play a central role in our study. We shall see that various approximations to the ML formulation are possible, leading to different estimation methods.
Umberto Mengali, Aldo N. D’Andrea
openaire   +1 more source

Multiplier-free Carrier Phase Estimation for Low Complexity Carrier Frequency and Phase Recovery

National Fiber Optic Engineers Conference, 2012
Carrier phase estimation for QPSK modulation is demonstrated using only real-valued additions without any multiplication or angle computation. Based on simulation and offline data, the same performance as the widely considered 4th-power algorithm is reached.
J. Qi, F. N. Hauske
openaire   +1 more source

Joint Carrier Phase and Symbol Timing Recovery for PAM Systems

IEEE Transactions on Communications, 1980
The detection of pulse amplitude modulation (PAM) carrier signals requires accurate symbol timing and carrier phase references. In most cases, it is desired to estimate these parameters directly from measurements on the received data signal. This paper adds to and unifies the theory of maximum likelihood [ML] estimation as applied to PAM timing and ...
Martin H. Meyers, Lewis E. Franks
openaire   +2 more sources

Carrier phase recovery issues in polyspectra-based equalizers

[Proceedings] ICASSP 91: 1991 International Conference on Acoustics, Speech, and Signal Processing, 1991
The sensitivity of the tricepstrum equalization algorithm (TEA) to imperfect carrier phase recovery is discussed. Structures of combined TEA-based equalization and carrier phase tracking are proposed. Performance evaluation of the proposed structures is made by means of computer simulations.
openaire   +1 more source