In this paper, a new structure is provided for the dispersion compensating photonic crystal fibers in order to broaden the chromatic dispersion and increase the dispersion compensating capability in a wide wavelength range. In the structure, putting a combination of circular holes and a star structure in the inner core clad causes the dispersion coefficient profile to be broadened, and addition...

In this paper, we present and compare three novel model-cum-data-driven channel estimation procedures in a millimeter-wave Multi-Input Multi-Output (MIMO) Orthogonal Frequency Division Multiplexing (OFDM) wireless communication system. The transceivers employ hybrid analog-digital architecture. We adapt techniques from wide range of signal processing methods, such as detection theories, compres...

Non-repudiation is a security service that provides cryptographic evidence to support the settlement of disputes. In this paper, we introduce the state-of-the-art of multi-party non-repudiation protocols, and analyze the previous work where one originator is able to send the same message to many recipients. We propose a new multi-party non-repudiation protocol for sending different messages to ...

Purpose – The aim of this study is to examine relation between employees’ participation in the organizations decisions making and their psychological empowerment in Iran Telecommunication Company subsidiary of Mazanderan Province. Design / methodology /approach- 250 employees from the Iran Telecommunication Company subsidiary of Mazanderan Province participated in this study. A Spearman's cor...

Distributed Feature Composition (DFC) is a new component-based architecture for telecommunication services. Its principles are similar to the well-known pipe-and-filter architecture, adapted for use in the telecommunication domain. We present an overview of this architecture and explain how it might be used as a basis for componentbased development of telecommunication software. We also describ...

We evaluate new interference suppression method that utilizes the effect of asynchronous accesses in wireless telecommunication. The method is called as asynchronous channels (ACL), which can be applied to one of the present third generation standards, wideband code division multiple access (W-CDMA) systems. The simulation result shows that the system capacity gains up by 145% in band-unlimited...

The future wireless networks envision ultra-reliable communication with efficient use of the limited wireless channel resources. Closed-loop repetition protocols where retransmission of a packet is enabled using a feedback channel has been adopted since early days of wireless telecommunication. Protocols such as automatic repeat request (ARQ) are used in today’s wireless technologies as a mean ...

In this paper, we propose a new homogeneous burst structure for the time-division duplex (TDD) component of the universal mobile telecommunication system (UMTS). The midamble period is removed and replaced by a data field to enhance the system’s spectrum efficiency. Alternatively, a pilot signal is loaded into one of these bursts over each time slot, in order to ensure a continuous channel trac...

Telemedicine provides medical information and services using telecommunication technologies. It includes systems for remote clinical care and consultation through the use of electronic imaging equipment. In wireless telemedicine, broadband multimedia information that is a combination of video, audio and externally acquired images is transmitted. Emergency medicine helicopters take an important ...