LTE’s study phase began in late 2004. The overall goal was to select technology that would keep 3GPP’s Universal Mobile Telecommunications System (UMTS) at the forefront of mobile wireless well into the next decade. Key project objectives were set in the following areas: peak data throughput; spectral efficiency; flexible channel bandwidths; latency; device complexity; and overall system cost. The main decision was whether to pursue the objectives by continuing to evolve the existing W-CDMA air interface (which incorporates HSPA (highspeed packet access) or adopt a new air interface based on OFDM. arabic 5 English 27
Mariam Abojela Msaad, Amer R. Zerek, Fareda A. Elmaryami(1-2014)

In this paper, a performance analysis study for VoIP over mobile wireless ad hoc networks (MANET) is carried out using OPNET tool. The AODV, DSR, TORA, OLSR, and GRP routing protocols have been used as candidates to evaluate the impact of routing on quality of service (QoS) of VoIP application over MANET networks. Three different queuing mechanisms (FIFO, PQ, and WFQ) have been used also as nominee of queuing techniques. The VoIP is applied and the QoS is measured in terms of jitter delay, end-to-end packet delay, and wireless LAN media access delay and wireless throughput of 802.11 g technology with 54 Mbps
Azeddien M. Sllame(1-2022)

This paper describes the usage of OPNET simulation tool to evaluate VoIP over MPLS networks which employs RSVP protocol as QoS mechanism with SIP or H.323 as signaling protocols for setting up VoIP calls over the Internet. The results showed that the H.323 with RSVP over MPLS networks produced minimal end-to-end delay than SIP protocol; making it a good choice as a signaling protocol with VoIP over MPLS networks for places requiring minimal end-to-end delay, while SIP reported lowest delay jitter with minimal call setup time
Azeddien M. Sllame, Asra Hema, Huda Alnajem(3-2018)