— this paper offers a summary of hybrid MAC Protocols that square measure designed exploitation FDMA, TDMA and CSMA approaches, giving it the flexibility to adapt to traffic and topology changes. It adopts a TDMA/FDMA/CSMA approach to beat the downside that is facing as individual protocol exploitation single approach. ZMAC, IHMAC, IMAC, BAZ-MAC, PHMAC, ERMAC like these there square measure man...

This paper presents the leading technologies for the next generation wireless telecommunication networks, LTE and WiMAX. Furthermore, the used modulation and multiplexing schemes such as QPSK, QAM, OFDM, OFDMA, SC-FDMA and MIMO will be shown. In addition, the network architecture and the basic characteristics of each 4G network approach will be presented. This is followed by a discussion where ...

In conventional wireless systems, unless a contiguous frequency band with width at least equal to the required bandwidth is obtained, multimedia communication can not be effected with the desired Quality of Service. We propose here a novel channel allocation technique to overcome this limitation in a Cognitive Radio Network which is based on utilizing several non-contiguous channels, each of wi...

In this paper a joint resource allocation problem is studied in a multi-service Single Carrier FDMA (SC-FDMA) wireless network. Mobile users request various services with different Quality of Service (QoS) characteristics and they determine in a distributed and non-cooperative manner a joint subcarrier and power allocation towards fulfilling their QoS prerequisites. Initially, a well-designed u...

Long Term Evolution (LTE) is consents pliable spectrum distribution which renders enriched wireless data services to users at lower latency and multi-megabit throughput. LTE uses Orthogonal Frequency Division Multiple Access (OFDMA) and Single Carrier Frequency Division Multiple Access (Sc-FDMA) for downlink and Uplink transmission where OFDMA has been acquired in LTE for downlink transmission ...

In the growth of fourth-generation mobile servicing, long` c ns term evolution (LTE) is an emanate technology. In LTE the downlink model build up on orthogonal frequency division multiple access (OFDMA) and the uplink arrangement build up on single carrier frequency division multiple access (SC-FDMA).In this paper we have tendency to derive the achievement of typical elemental differences betwe...

Throughout wireless communication systems, Orthogonal Frequency Division Multiplexing (OFDM) and also Single-Carrier Frequency Division Multiple Access(SC-FDMA) contributes a significant part. It has been adopted by a variety of future mobile communication standards like WiMAX, Long-term Evolution (LTE), LTEAdvanced and also Ultra Mobile Broadband (UMB) and many others. SC-FDMA can be interpret...

In wireless communication, multiplexing & multiple access concept is most important. In most communication systems require, sharing of channels. In Multiple Access techniques types such as FDMA, TDMA, CDMA, & OFDM. OFDM based transmission system uses CP in an MB-OFDM symbol in order to maintain the orthogonality of Trasmission.Present days ultra-wideband systems use multi-band OFDM techniques f...

Using multiple channels in wireless sensor networks helps increase the overall throughput and avoid interferences. In addition, introducing multi-interface nodes further helps in increasing the packet delivery rate for those specific nodes. In this paper, we evaluate a channel allocation method based on neighborhood discovery up to 3 hops and a hybrid MAC protocol designed for high data rate wi...