Volume 17, Issue 1, November 2012

Analysis and Design of Narrow Band Filters for Telecommunications Applications [Full Text]

Adiba Elfadl, Lekbir Belrhiti, Hamid Bouyghf and Seddik Bri

Abstract—In this paper, we have developed the microwave theory and analyzed the filter design for telecom applications. The software ADS (Advanced Design System) is used for design bandpass filter with microstrip lines coupled (McLin) Chebychev type of order 5 at the center frequency f = 2.4 GHz with 10% bandwidth. The topology of a DBR filter (Dual Behavior Resonator) of order 2 of a chain 2.14 GHz is simulated. The design of a filter types that Tchebysheve 0.1dB ripple in the pass band with a standard bandwidth of 2% and a center frequency fo = 5.8 GHz using a ring resonator and the ring resonator side coupled to access quarter wavelength for a center frequency of 94 GHz. 


Broadcast Monitoring and Applications [Full Text]

Agbaje M. Olugbenga, Awodele O., and Idowu S.A.

Abstract— Broadcast monitoring is the process of tracking and observing activities on broadcasting channels in compliance with intellectual property rights and other illegal activities not conforming to broadcasting laws using the computer or human system. The problem here has a unique challenge from the pattern recognition point of view because a very high recognition rate is needed under non- ideal conditions. There is also a problem in comparing a small audio sequence with a large audio stream (the broadcast) searching for matches. Broadcast monitoring could be active or passive. In this paper we did a review of the various application and techniques useful to broadcast monitoring systems. 


Advantages of Client Partitioning for Content Delivery [Full Text]

Kenichi Yamashita and Kazumasa Oida

Abstract—In the content delivery networks (CDNs), there are basically two ways to set up client and server pairs for delivering media streams. They are the server selection (SS) made by a requesting client and the client partitioning (CP) performed by all servers. The latter requires precise information on future request arrivals. Although previous works mainly focus on the SS approach, this paper takes the CP approach and proposes a revised version of an existing CP algorithm designed for hypercube overlays. The revised CP algorithm copes with requests from unexpected clients and outperforms the SS algorithm, especially when a large number of clients and servers exist, requesting clients are spatially concentrated, or a huge number of requests arrive in a short period of time (flash crowds). 


Setup Latency Analysis of CAPWAP Centralized WLAN Network [Full Text]

M. Balfaqih, A. Hashim, O. Mahmoud, M. H. Mazlan, S. Haseeb and S. N. Hasnan

Abstract—High number of Access Points (APs) in large-scale networks have introduced several overheads such as control, management and monitoring. Distributing and maintaining a consistent configuration while considering security issues presents even more challenges in large deployments and new architectures. These issues forced many network vendors such as Aruba, Cisco and Meraki to offer proprietary centralized solutions. Since the proposed solutions don’t provide any form of interoperability, Control and Provisioning of Wireless Access Point (CAPWAP) Working Group had defined standard interoperable protocol to address the aforementioned problems. By using Access Controller (AC) and Wireless Termination Point (WTP), this interoperable protocol allows network operators to control their wireless network infrastructure and extends manageability. This paper evaluates the latency involved with setup process in three cases; normal setup process, pre- configured setup process and setup process with considering failure states. The results showed that the main latency contributor is the Discovery phase, while the error during DTLS Establishment phase cost more time than other phases.