Nuredin Ahmed

Wireless Channel Model Based on SoC Design Methodology

In this paper, a new method to model and simulate a wireless communication system based on System on Chip design methodology will be presented. The network performance effected by the amount of detail in the simulation model. Hence there is a need to develop suitable abstractions that maintain the accuracy of the simulation while keeping the computational resource requirements low. The integration of communication modelling into the design modelling has been shown by modelling a noisy communication channel in SystemC. The channel supports different modulation techniques such as, Amplitude-shift keying, Phase-shift keying, Quadrature amplitude modulation. It supports the setting of different Signal to noise ratio and different types of interference for Point-to-Point and Point-to-Multipoint platforms based on SystemC design methodology.

RTL-level modeling of an 8B/10B encoder-decoder using SystemC

This paper presents an RTL-level model of an 8B/10B encoder/decoder block in SystemC. The use of 8B/10B coding is an important technique in the construction of high performance serial interfaces. These are particularly suitable for alleviating the I/O bottleneck of state of the art systems (which are pinout, rather than bandwidth limited). SystemC has been chosen because it provides a homogeneous design flow for complex designs (i.e. SoC and IP based design), where system modeling at the early stages of the design becomes increasingly important.

EC-CPW fed elevated patch antenna

This paper presents a novel G-band (140GHz - 220GHz) integrated antenna. The antenna incorporates a newly proposed elevated center coplanar waveguide (EC-CPW) fed elevated patch antenna on a high dielectric substrate (GaAs). The proposed antenna consists of an (EC-CPW) feed line, λ/4 transformer used for matching, supporting posts, and a 5.5μm height elevated radiating patch. The antenna topology effectively creates a low-substrate dielectric constant and hence eliminates undesired substrate effects, since the antenna substrate is essentially air, the lowest possible dielectric constant. This increases the radiation efficiency, gain, and the radiation bandwidth. Close agreement between simulated and measured data have shown a good match of -20dB at 172GHz and bandwidth of 7.9GHz from 169.2GHz to 177.1GHz (return loss<;10 dB). Furthermore, the presented antenna exhibits an excellent constant broadside radiation pattern which makes it ideal for array antennas applications where directionality is an important factor avoiding pixels interferences. In addition the proposed antenna fabrication process is compatible with III-V MMICs process technology. This makes it ideal for fully integrated millimeter wave focal plane arrays applications.

Wireless extension into existing SystemC design methodology

SystemC is established as a suitable design and modelling language. It provides a consistent methodology for the design and refinement of complex digital systems. This paper focuses on how wireless features can be incorporated into existing SystemC design methodology in order to use this methodology to model wireless systems. The SystemC modelling language currently lacks a standard framework that supports modelling of wireless communication systems (particularly the use of wireless communication channels). Three components must be investigated in order to achieve this target: the development of a system level model of a digital wireless communication channel that represents the core of any communication system, the creation of a small library of dedicated elements at system level, such as PLL (Phased Locked Loop), 8B/10B Encoder/Decoder and several communication protocols modelling, and a case study/demonstration validating wireless extension methodology. The first two parts have been modelled successful, so we now focus on modelling a flocking behaviour system and demonstrating how these parts integrate to achieve the target.

Measuring and Optimising Convergence and Stability in Terms of System Construction in SystemC

The current SystemC modelling language lacks a standard framework that supports the modelling of wireless communication systems. This research investigates how wireless features can be incorporated into existing SystemC design methodology. The components to be investigated in order to achieve this target are divided into three parts: developing a system-level model of a digital wireless communication channel, creating a small library of dedicated elements at system level, and concluding with a case study on flocking behaviour system to validate the wireless extension methodology. In previous works, all these parts were successfully modelled and implemented. In this paper, the integration of communication modelling is introduced into design modelling during the early stages of system development. We use a flocking behaviour system to show how the stability of the system and converging point are measured and optimised in terms of system construction, using some important concepts of graph theory.

Frequency reconfigurable proximity coupled patch antenna

This paper present a new design of frequency reconfigurable elevated patch antenna without using RF MEMS switch. It is well known that the patch height of the elevated patch antenna is one of the major factors in determining the antenna resonant frequency. By decreasing the patch height, the fringing fields from the patch edges will decrease, which decreases the extension in the patch length and hence the effective length of the patch, thereby increasing the resonance frequency. Therefore, the basic idea of this design is based on electrostatically adjusting the patch height to control the resonate frequency of the antenna. The measured return loss of the fabricated antenna in the up-position 0 volt, the resonant frequency of the antenna is about 189.2GHz with 18.7dB return loss. As the height of the patch reduced by applying the dc voltage, the resonant frequency shifts to 191GHz at 42volt dc voltage and with nearly the same bandwidth.

Dual-radios hypermesh network based on CSMA protocol

Recently, multi-radio mesh technology in wireless networks has been put under extensive research. This is because of its potential to overcome the inherent wireless multi-hop throughput, scalability and latency problems caused by the half-duplex nature of the IEEE 802.11. This paper introduces a design and modelling of different elements on a distinct type of multicomputer networks, the dual-radio wireless hypermesh (DIWH), based on SystemC methodology. The hepermesh is a well-known topology that belongs to the hypergraph family of networks. Hypermeshes have been proposed as potential alternatives to the graph networks for the future System Area Networks (SAN). In this work, we consider a two dimensional DIWH network, where each router node is equipped with two radio interfaces and two non-overlapping channels are available for each node. we address the problem of assigning channels to communication links in the network with the objective of keeping overall network latency low and provide a relatively high throughput. The simulations and analysis have shown that our design achieves a significant increase in network throughput with less average network latency for large number of communication nodes, compared with the CSMA shared channel model, which is currently the de facto MAC protocol for most wireless networks. Our simulations have been validated analytically to show the accuracy of the developed model. In addition, simulation results have shown that the wireless hypermesh outperforms shared medium wireless networks under the constant total bandwidth argument, especially in large networks.

Single and multi-channel networks: Performance comparison at system level

This paper presents an original development methodology for the use of SystemC to compare two different networks at the system level. A single cluster of a single channel network based on CSMA and multi-channel network cluster based on non-overlapping channels available for each node have been developed. In both network configurations a noiseless (error-free) channels are used, since the focus in this paper on channel assignment and validation of the results. Our simulations were validated analytically to show the accuracy of the developed model. Performance results for the simulations as well as development effort are presented thus showing how this methodology is well suited to the modelling of relatively large networks. Moreover the experience of using SystemC design methodology to analyse the performance properties of wireless communication network is presented.

Modeling of Flocking Behaviour System in SystemC

This paper introduces the integration of communication modelling into design modelling during the early stages of system development. It presents the modelling of flocking behaviour system in SystemC, which is emerging as a suitable language for designing and modelling. SystemC provides a consistent methodology for the design and refinement of complex digital systems. In this paper, a demonstrator implementing communication between particles has been constructed and incorporated into the entire design methodology. The communication has been implemented through the incorporation of a wireless channel that was previously modelled.