Results 211 to 220 of about 76,661 (236)

Transmission of 200-GBaud PDM Probabilistically Shaped 64-QAM Signals Modulated via a 100-GHz Thin-film LiNbO3 I/Q Modulator

Optical Fiber Communications Conference and Exhibition, 2021
Xi Chen, G. Raybon, D. Che, Junho Cho, K. Kim   +4 more
semanticscholar   +1 more source

Design and Analysis of SCMA Codebook Based on Star-QAM Signaling Constellations

IEEE Transactions on Vehicular Technology, 2018
In this paper, a novel codebook design method for sparse code multiple access (SCMA) is proposed and an analytical framework to evaluate the bit error rate (BER) performance is developed.
Lisu Yu, P. Fan, Donghong Cai, Zheng Ma
semanticscholar   +1 more source

Multi-Carrier QAM Modulator

2001
For several years, code-division multiple access (CDMA) systems have gained widespread interest in mobile wireless communications. Wideband code division multiple access (WCDMA) [ETSI98] uses a wider channel compared to a narrowband CDMA channel [TIA93], which improves frequency diversity effects and therefore reduces fading problems.
Jouko Vankka, Kari Halonen
openaire   +1 more source

Experimental Comparison of 64-QAM and Combined Geometric-Probabilistic Shaped 64-QAM

2017 European Conference on Optical Communication (ECOC), 2017
We present a novel format of combined geometric-probabilistic shaped QAM constellation. We measure about 1 dB sensitivity gain compared to conventional 64-QAM at 54.2 GBaud and 25% of overhead under different scenarios including back-to-back, single-channel and WDM transmissions.
Fanny Jardel, Tobias A. Eriksson, Fred Buchali, Wilfried Idler, Amirhossein Ghazisaeidi, Cyril Measson, Joseph J. Boutros   +6 more
openaire   +1 more source

Performance of Massive-MIMO OFDM system with M-QAM Modulation based on LS Channel Estimation

2019 International Conference on Advanced Systems and Emergent Technologies (IC_ASET), 2019
A Least Squares Channel Estimation (LSCE) method is designated for a Massive MIMO system combined with Orthogonal Frequency Division Multiplexing (OFDM) and higher order modulation technique.
Abdelhamid Riadi, M. Boulouird, M. Hassani   +2 more
semanticscholar   +1 more source

FPGA QAM Demodulator Design

2002
Bandwidth efficient communication systems employ highorder modulation schemes like M-ary QAM modulation for reasons of spectral efficiency. Many sophisticated signal processing algorithms are implemented in a QAM demodulator, including adaptive equalization, timing recovery, carrier recovery, automatic gain control and digital down conversion to name a
Chris Dick, Fred Harris
openaire   +1 more source

A ${D}$ -Band Digital Transmitter with 64-QAM and OFDM Free-Space Constellation Formation

IEEE Journal of Solid-State Circuits, 2018
A ${D}$ -band I/Q RF-DAC featuring two 6-bit DAC elements driven in quadrature, each with its own on-die antenna, and a total effective isotropic radiated power (EIRP) of 13.2 dBm, is demonstrated in a 45-nm SOI-CMOS technology.
S. Shopov, O. Gurbuz, Gabriel M. Rebeiz, S. Voinigescu   +3 more
semanticscholar   +1 more source

QAM for terrestrial and cable transmission

IEEE Transactions on Consumer Electronics, 1995
We introduce quadrature amplitude modulation (QAM) and discuss QAM architectures used to overcome transmission impairments typically encountered on 6 MHz wide terrestrial and cable TV VHF/UHF channels. The input data to the QAM transmitter is mapped into N bit words called symbols; N determines the QAM level.
openaire   +1 more source

Understanding the error performance of 16-QAM, 32-QAM, 64-QAM, 256-QAM

2020
Trinder, Julian, M A Ceng
openaire   +1 more source

New Constructions of Perfect 8-QAM+/8-QAM Sequences

IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, 2014
Chengqian XU, Xiaoyu CHEN, Kai LIU
openaire   +1 more source