Results 141 to 150 of about 637,226 (201)
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IEEE Journal on Selected Areas in Communications, 2001
A multicarrier Gaussian minimum shift keying (GMSK) modulator has been developed and implemented. The design contains four GMSK modulators, which generate GMSK modulated carriers at the specified center frequencies. Utilization of the redundancy in the stored waveforms reduces the size of the GMSK trajectory look-up table to less than one-quarter of ...
Jouko Vankka +2 more
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A multicarrier Gaussian minimum shift keying (GMSK) modulator has been developed and implemented. The design contains four GMSK modulators, which generate GMSK modulated carriers at the specified center frequencies. Utilization of the redundancy in the stored waveforms reduces the size of the GMSK trajectory look-up table to less than one-quarter of ...
Jouko Vankka +2 more
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ISCAS'99. Proceedings of the 1999 IEEE International Symposium on Circuits and Systems VLSI (Cat. No.99CH36349), 2003
A multicarrier QAM modulator has been developed and simulated. The multicarrier QAM modulator contains four upconversion circuits. Each upconverting circuit accepts 12 b in-phase and quadrature data streams, interpolates those by 16 and upconverts the baseband signal to a selected center frequency.
Jouko Vankka +2 more
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A multicarrier QAM modulator has been developed and simulated. The multicarrier QAM modulator contains four upconversion circuits. Each upconverting circuit accepts 12 b in-phase and quadrature data streams, interpolates those by 16 and upconverts the baseband signal to a selected center frequency.
Jouko Vankka +2 more
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Multicarrier modulation for HF communications
2016 International Conference on Military Communications and Information Systems (ICMCIS), 2016High-frequency (HF) communications can be flexibly realized using multicarrier modulation techniques. This paper compares the performance of three widely utilized MCM techniques, namely, orthogonal frequency-division multiplexing (OFDM), filter bank multicarrier/offset-QAM (FBMC/OQAM), and filtered multitone (FMT) in HF communications.
Juha Yli-Kaakinen +2 more
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Multicarrier delay diversity modulation
GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489), 2005Multicarrier delay diversity modulation (MDDM) is a scheme that uses orthogonal frequency division multiplexing (OFDM) on a "multipath" channel that is generated by using delay diversity. The full diversity criterion for MDDM is proven and illustrative examples of full-diversity codes are obtained based on the established criterion.
Jun Tan 0002, Gordon L. Stüber
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IEEE Transactions on Circuits and Systems II: Analog and Digital Signal Processing, 2000
A multicarrier quadrature amplitude modulation (QAM) modulator has been developed and implemented with programmable logic devices. The multicarrier QAM modulator contains four CORDIC-based QAM modulators. A conventional QAM modulator needs two multipliers, one adder, and sine/cosine ROM's.
J. Vankka +3 more
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A multicarrier quadrature amplitude modulation (QAM) modulator has been developed and implemented with programmable logic devices. The multicarrier QAM modulator contains four CORDIC-based QAM modulators. A conventional QAM modulator needs two multipliers, one adder, and sine/cosine ROM's.
J. Vankka +3 more
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Multicarrier Modulation and OFDM
2021The division of a frequency band into dedicated channels by modulation, called frequency-division multiplexing (FDM), has a long history. Prominent examples are the analog telephone networks until the 1970s. They were replaced by digital telephony, operating with time-division multiplex (TDM), in which dedicated time slot are allocated to each ...
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A multicarrier QAM modulator for WCDMA basestation
2000 IEEE International Symposium on Circuits and Systems. Emerging Technologies for the 21st Century. Proceedings (IEEE Cat No.00CH36353), 2002A multicarrier QAM modulator for the wideband code division multiple access (WCDMA) basestation has been designed. The multicarrier modulator performs pulse shaping filtering for four baseband I and Q data streams. The filtered data is interpolated in three stages each interpolating with a factor of two.
Marko Kosunen +2 more
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Proportionally Sampled Multicarrier Modulation
2008 IEEE International Conference on Communications, 2008A new proportionally sampled multicarrier modulation (PSMCM) system with optimum receiver is presented in this paper. By adopting different sampling rates at transmitter and receiver, the PSMCM system can achieve multipath diversity with simple linear operations.
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Retransmission diversity schemes for multicarrier modulations
IEEE Transactions on Wireless Communications, 2006In this work, we present some simple techniques for enhancing the diversity provided by retransmissions in OFDM and DMT modulations. The primary techniques of interest are symbol interleaving and mapping diversity for retransmissions. Symbol interleaving involves retransmitting packet symbols through different subcarriers of the same channel, while ...
Harvind Samra, Zhi Ding 0001
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Complex wavelet packets for multicarrier modulation
Proceedings of the 1998 IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP '98 (Cat. No.98CH36181), 2002We first discuss two approaches for designing complex wavelet packets which can be used as orthogonal carriers for modulations like QAM and PM, and then compare the performance of the wavelet packet based modulation scheme with that of discrete multitone modulation using DFT bases.
Tushar K. Adhikary, Vellenki U. Reddy
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