Raziq Yaqub

Autonomous Heterogeneous Networks Discovery Technique

Increased efforts directed to enable ubiquitous services across heterogeneous radio access technologies has given birth to seamless integration of heterogeneous wireless networks. It necessitates smooth and seamless handover over heterogeneous wireless networks. Seamless handover imposes stringent requirements like rapid network discovery, quick selection of candidate networks and proactive handover actions. This paper proposes a method wherein a mobile node becomes capable of autonomously discovering presence of networks and related information. The proposed method of acquiring information by autonomous discovery is to be used to support proactive handover actions

Architecture supporting network discovery in future heterogeneous networks

The aim of this research paper is to critically analyze one of the integrated WLAN-cellular network architecture which third generation partnership project (3GPP) has also included in its release 6 i.e. generic access network (GAN) formally called unlicensed mobile access (UMA). This article analyzes the limitations of the above mentioned solution and present an architecture for future heterogeneous networks using a novel hybrid approach of network discovery, where the network will broadcast the updated network information using cell broadcast center (CBC) to the mobile station/user equipment (MS) and the MS may also enquire from the network the additional information regarding the available networks, as opposed to centralized technique used in the existing cellular networks. The proposed solution suggests a network information repository (NIR) embedded in the core network, being populated with information of all the available radio access networks (RANs) in a specific location. The information obtained from NIR will help the MS to identify the network elements ahead of time and communicate with these elements in advance. This will help the MS to fetch the general information about the available networks and select the desired network ahead of time and thus seamless connectivity/ handover will be possible for the end user.

Time-tag based efficient information access

Rapid increase in applications of mobile networking technologies has fuelled the need for seamless handover across homogeneous and heterogeneous networks. Seamless handover warrants stringent requirements like real-time information availability, rapid network discovery, quick selection of candidate networks and proactive handover actions. Existing network discovery mechanisms involve either direct interaction of mobile client (MC) with the candidate network or through sending queries to knowledge server like media independent information server (MIIS). Our method will make the MC-MIIS query response communication optimum and efficient. This will not only reduce any superfluous traffic on the network but also eliminate unnecessary burden on the MIIS thus making the interaction between MIIS and MC robust and efficient

Network discovery approach in heterogeneous radio access networks

The emerging future heterogeneous wireless networks intend to provide a variety of adaptable services to mobile and nomadic users by using integrated heterogeneous network infrastructure. These networks are envisioned as the integration of different existing wireless network technologies such as WLAN, WiMAX, 2G, 2.5G, 3G, Bluetooth, etc., and future wireless network technologies. To integrate different network into a single heterogeneous network, the mobile station/user equipment (MS/UE) must discover all the available radio access networks ahead of time, select the appropriate network from the available radio access networks (RANs) and then seamlessly hand over the session to the desired/chosen network. This research paper presents a novel hybrid approach for network discovery, where the network will broadcast the updated network information using cell broadcast center (CBC) to the MS/UE and the MS/UE may also enquire from the network the additional information regarding the available networks, as opposed to centralized technique used in the existing cellular networks. The proposed solution suggests a network information repository (NIR) embedded in the core network, having the information of all the available radio access networks (RANs) in a specific location. The NIR will be populated and updated by the reporting agents (RAs) which are normal MS/UEs

Network Discovery Through Moving Networks-Information-Server

This paper proposes a new approach for networks discovery. It comprises of a moving information server (MIS) installed in the vehicles e.g. trains, trams, buses, or any mass public transport system, etc. It provides information, ahead of time; to the mobile nodes (MNs) sitting in the vehicles, about the available networks in the geographical domain the vehicle is passing through or about to pass through. The MIS maintains the updated list of the known networks mapped with the location information. MIS collects networks information by receiving radio signals from the networks and or by actually connecting to the networks that fall on the track/route of the vehicle, and the location information through GPS receiver. It is assumed that MIS in public vehicles can keep the updated information about the networks because it will pass through the same networks on the route it goes over several times a day. MNs can receive networks information from MIS through broadcast, or query-response, or combination of both. MIS is multiple interface device capable of delivering information on multiple radio interface (e.g., IEEE 802.11, 802.16, 3GPP or 3GPP2). MN can pick the information through an interface it is currently using. The MIS can be connected to the core network via an appropriate wireless link or broadband power line (BPL) to provide additional services. The document is organized as follows. Section 1 presents Introduction coupled with the drawbacks of the prior arts. Section 2 explains our proposed approach, Section 3 lists some Merits of the proposed solution and finally Section 4 lists References.

Seamless handoff based on Network Discovery for Future Heterogeneous Mobile Networks

The aim of this article is to present a novel handover algorithm to decrease the handoff latency in all-IP based Future Heterogeneous Mobile Communication System (FHMCS). The reduction in handoff latency is achieved by employing Mobile Network Discovery Technique which will decrease the delays due to movement detection, new Care of Address Configuration and Duplicate Address Detection (DAD). The decrease in handoff latency will reduce the probability of packet loss and handoff failures thus provide seamless communication and support for real time applications. The Network Discovery is achieved by using our proposed Mobile Network Information Repository, available at the site of Mobile Virtual Network Operator (MVNO), a third party operator. This network information will be available to legitimate users of all Mobile Network Operators having a single Service Level Agreement (SLA) with MVNO. In this article, we propose an intelligent handover algorithm to decrease the handover delay and thus optimizing the inter-technology handover for all-IP based Future Heterogeneous Mobile Communication System.

Effect of Speech Activity Detection in IEEE 802.11 Wireless Networks

VoIP over Wireless-LAN (VoWLAN) is gaining importance due to its excellent potential in wireless voice communication. With the rapid deployment of WLANs, there is a growing demand for WLANs to support voice applications. In this research paper we present simulation results by enabling the Speech Activity Detection (SAD) for seven codecs, i.e. G.711, G.723.1, G.729, G.726 (ADPCM), G.728 (LD-CEPT), G.729 (CS-ACELP), and GSM under similar load conditions for interactive Voice over WLAN system on the IEEE 802.11 wireless LAN standard. Additionally, results have also been obtained by disabling Speech Activity Detection and both sets of results have been compared. The primary metric used in the comparison is packet end-to-end delay. From our results we conclude that the use of the Speech Activity Detection significantly improves the Average Packet end-to-end delay and slightly improves the Average Packet Delay variation for all of the aforementioned vocoders. The G.723.1 vocoder provides the least end-to-end delay and packet delay variation under both conditions, i.e. with enabled and disabled SAD. With enabled SAD, the average end-to-end delay improves by approximately 58% for our experiments.

Inter and intrasystem nonlinearity compensation for radio on fiber considering wideband CDMA air-interface

This paper addresses both the intersystem and intrasystem intermodulation distortions (IMD) for radio on fiber considering the wideband CDMA (WCDMA) air interface. For radio on fiber configuration, base stations (BS) receive RF signals from mobiles and transmit them to the radio network controller (RNC) on an optical fiber channel. Since a WCDMA BS is exposed to the whole cellular spectrum, it receives a comb of frequencies of other cellular systems operating in the same geographical area. This provokes intersystem IMD. Apart from this, the CDMA BS is also subjected to the intrasystem IMD instituted by its own CDMA mobile users due to the nonlinearity of the power amplifier (PA). Moreover as the system is optical fiber feeder, the laser diodes (LD) nonlinearity also incites the IMD due to a clipping effect. The nonlinearities instituted by PA and LD can be regarded as intrasystem IMD. In this paper all these IMD are addressed through a unified operation of FEC codes and post-nonlinearity recovery block (PNRB).