نتایج جستجو برای: ofdm modulation
تعداد نتایج: 158324 فیلتر نتایج به سال:
Wireless communications became an integrated part of the human life. Fifth generation (5G) is modern communication which provides enhanced mobile broadband (eMBB), ultra reliable low latency (URLLC), and massive machine type (mMTC). Thus, 5G have to provide coverage multi-numerology devices, therefore, modulation access schemes are suggested in literature such as cyclic prefix orthogonal freque...
This article deals with channel estimation (CE) in orthogonal frequency division multiplexing (OFDM)/OQAM. After a brief presentation of the OFDM/OQAM modulation scheme, we present the CE problem in OFDM/OQAM. Indeed, OFDM/OQAM only provides real orthogonality therefore the CE technique used in cyclic prefix-OFDM cannot be applied in OFDM/OQAM context. However, some techniques based on imaginar...
The increasing demand on real time application to achieve high throughput, reliable wireless system and network capacity for fourth generation wireless local area networks is to combine MIMO wireless technology with OFDM. Orthogonal Frequency Division Multiplexing (OFDM), which offers reliable high bit rate wireless system with reasonable low complexity. OFDM does provide large data rates with ...
Visible light communications (VLC) technology permits the exploitation of light-emitting diode (LED) luminaries for simultaneous illumination and broadband wireless communication. Optical orthogonal frequency-division multiplexing (O-OFDM) is a promising modulation technique for VLC systems, in which the real-valued O-OFDM baseband signal is used to modulate the instantaneous power of the optic...
The migration to 4G networks will bring a new level of expectation to wireless communications. As after digital wireless revolution made mobile phones available for everyone, the higher speeds and packet delivery of 4G networks will make high quality multimedia available everywhere. The key to achieving this higher level of service delivery is a new air interface. Orthogonal Frequency Division ...
In this paper, we apply polar codes to a modified version of OFDM systems with index modulation which is called in-phase/quadrature (OFDM-I/Q-IM). We provide general design guidelines for the proposed polar-coded OFDM-I/Q-IM systems. system, at transmitter, employ random frozen bits appending scheme not only makes code compatible but also improves bit error rate (BER) performance system. Furthe...
In this paper, a survey on different modulation schemes having lowest peak to average power ratio (PAPR) value for use in uplink communication has been studied. OFDM has become the popular modulation choice for high data rate wireless communication systems. It can provide multi-path delay spread tolerance and is robust to channel dispersions. But one of the major limitations of OFDM is the larg...
This paper deals with the combination of OFDM/OQAM with the Alamouti scheme. After a brief presentation of the OFDM/OQAM modulation scheme, we introduce the fact that the well-known Alamouti decoding scheme cannot be simply applied to this modulation. Indeed, the Alamouti coding scheme requires a complex orthogonality property; whereas OFDM/OQAM only provides real orthogonality. However, as we ...
High peak-to-average power ratio of the transmit signal is a major drawback of multicarrier transmission such as OFDM. This paper describes Orthogonal Frequency Division Multiplexing (OFDM) system with Continuous Phase Modulation (CPM) mappers is considered. Such a system is known to provide superior bit error rate performance by virtue of the memory introduced by the CPM mapper compared to OFD...
In this paper, we present a comparison between MCCDMA and CDMA-OFDM/OQAM systems in the case of MIMO channel. The advanced Multi Carrier CDMA OFDM/OQAM modulation is a combination of CDMA and OFDM/OQAM. This combination takes advantages from multicarrier modulation and spread spectrum. Indeed, the use of OFDM has proved its ability to fight against frequency selective channels but the insertion...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید