Results 21 to 30 of about 9,046,388 (244)

Frequency hopped CDMA for third generation mobile radio systems [PDF]

, 1993
Third generation mobile radio systems will provide unified mobile access to a wide range of services for the mass user market. Code division multiple access (CDMA) is one of the most viable access techniques to provide the flexible air interface required.
Purle, DJ, Swales, SC, McGeehan, JP, Beach, MA   +3 more
core   +1 more source

Noncoherent Multi-Way Relay Based on Fast Frequency-Hopping M-ary Frequency-Shift Keying [PDF]

, 2010
Information exchange among a group of users is implemented with the aid of fast frequency-hopping $M$-ary frequency-shift keying multi-way relay (FFH/MFSK MWR). The FFH/MFSK MWR scheme uses two time-slots per symbol for achieving the information exchange,
Cao, Jianfei, Yang, Lie-Liang, Zhong, Zhangdui   +2 more
core   +2 more sources

Low-Hit-Zone Frequency/Time Hopping Sequence Sets With Large Family Size

IEEE Access, 2019
For a quasi-synchronous frequency/time hopping (FH/TH) code-division multiple-access (CDMA) system which involves many users, the low-hit-zone (LHZ) FH/TH sequence set with large family size is necessary.
Xing Liu, Qin Shu, Qi Zeng
doaj   +1 more source

Spreading Sequence Design and Theoretical Limits for Quasisynchronous CDMA Systems

EURASIP Journal on Wireless Communications and Networking, 2004
For various quasisynchronous (QS) CDMA systems such as LAS-CDMA system which emerged recently, in order to reduce or eliminate the multiple access interference and multipath interference, it is required to design a set of spreading sequences which are ...
Fan Pingzhi
doaj   +2 more sources

Constructions of Low-Hit-Zone Frequency-Hopping Sequence Set With Strictly Optimal Periodic Partial Hamming Correlation

IEEE Access
Frequency-hopping technology has been used widely in wireless communications, especially in military communications and in civil mobile communications.
Chun Xie, Changyuan Wang
doaj   +1 more source

A Construction Method for the Random Factor-Based G Function

Applied Sciences
In consideration of the prevailing methodology for constructing G functions, there are certain limitations such as fixed change rules and restricted flexibility when producing frequency-hopping sequences. This paper introduces a novel construction method
Yongxin Feng, Jiankai Su, Bo Qian
doaj   +1 more source

Area spectral efficiency of soft-decision space–time–frequency shift-keying-aided slow-frequency-hopping multiple access [PDF]

, 2012
Slow-frequency-hopping multiple access (SFHMA) can provide inherent frequency diversity and beneficially randomize the effects of cochannel interference.
Ngo, Hoang Anh, Hoang Anh Ngo, Hanzo, Lajos, Lajos Hanzo   +3 more
core   +1 more source

No-Hit-Zone Frequency-Hopping Sequence Sets with Optimal Hamming Autocorrelation

IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, 2010
In quasi-synchronous frequency-hopping multiple access (QS-FHMA) systems, no-hit-zone frequency-hopping sequence (NHZ-FHS) sets are commonly employed to minimize multiple access interference. Several new constructions for optimal NHZ-FHS sets are presented in this paper, which are based on interleaving techniques. Two types of NHZ-FHS sets of length 2N
Chung, JH, Han, YK, Yang, K
openaire   +6 more sources

Deep Reinforcement Learning-Based Anti-Jamming Approach for Fast Frequency Hopping Systems

IEEE Open Journal of the Communications Society
Increasing the hopping frequency speed and integrating artificial intelligence (AI) technologies are currently two of the most effective strategies for enhancing the anti-jamming performance of frequency hopping (FH) systems.
Sixi Cheng, Xiang Ling, Lidong Zhu
doaj   +1 more source

Hyperosmotic stress‐induced redistribution of pre‐mRNA cleavage factor I subunits is associated with shifts in alternative polyadenylation

FEBS Open Bio, EarlyView.
Hyperosmotic stress triggers the relocation of the CFIm complex from the nucleus to the cytoplasm. This shift creates a nuclear ‘stoichiometric bottleneck’, limiting CFIm availability for mRNA processing. Consequently, specific mRNAs like NUDT21 and DICER1 undergo targeted 3′UTR shortening, demonstrating how spatial protein dynamics drive rapid ...
Hitomi Soumiya, Masatake Osawa, Hidefumi Fukumitsu   +2 more
wiley   +1 more source