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HA NOI UNIVERSITY OF SCIENCE AND TECHNOLOGY ELECTRICAL AND ELECTRONICS ENGINEERING Design Project I Simulation of routers of mobile ad-hoc network and evaluate data transmission of network using UDP through wireless channel Instructor: Dang Quang Hieu Class: ET-E4 K63 Name: Le Bao Ngoc Student ID: 20182930 TABLE OF CONTENTS I) Overview of our project II) Technical characteristic of MANETs III) Routing of MANETs IV) Implement MANETs on NS3 V) Wireless channel VI) Image transmission through wireless channel(implementation on Jupyter Notebook) VII) Evaluate image transmission of MANETs network and wireless channel I) OVERVIEW OF MY PROJECT A.Overview In recent years, with the dramatic improvement of data structures and algorithmic techniques with fundamental techniques of measurement with network communication is the foundation of this field Before concluding this resource, we have a report on subject that we learn and practice during this by making a simple server to test the loss propagation and the survey with data rate of my server With the knowledge I have learned about , I will find the best form of my server and get the best simple server, avoid packet loss when doing and researching a more complicated server B.Development history -Mobile Ad-hoc Network - MANET was formerly known as wireless network package, and funded, developed by DARPA in the early 1970s -Then a new network: SUSAN (Adaptive Survivable Network) was proposed published by DARPA in 1983 to support a larger, more robust network stronger This time, Ad-hoc was used to describe a type of network such as IEEE802.11 standard C.Purpose -Build up a server with full infrastructure is so costly and not reasonable Some places don’t have condition: Sponsor, Geography location, Facilities,… So, we need to build a wireless communication network without infrastructure to ensure that mobile device or electronics can transmiss and get information conveniently over nodes and interconnection of server It is model of mobile ad hoc netwook(MANETs) MANETs architecture D.Basic knowledge of MANETs The Mobile Adhoc Network (MANET) consists of loosely interconnected router domains A MANET is characterized by one or more MANET network interfaces, which are distinguished by their time-varying "asymmetric accessibility" to neighboring routers These routers identify and maintain a routing structure between them Routers can communicate over dynamic radio channels with asymmetric access, are mobile, and can join or leave the network at any time In order to communicate with each other, adhoc nodes need to configure their network interface with local addresses that are valid in the area of that adhoc network Adhoc nodes may have to configure routable global addresses to communicate with other devices on the Internet From an IP layer perspective, the MANET acts as a Layer multi-hop network made up of links Therefore, each adhoc node in the MANET will act as a Layer router to provide connectivity to other nodes in the network Each adhoc node maintains routes to other nodes in the MANET and network routes to destination nodes outside of that MANET If connected to the Internet, MANETs become edge networks, meaning their borders are defined by edge-routers Due to the nature of the links that make up the MANET, the adhoc nodes in the network not share access for the multicast signaling single link Thus, in MANETs, there is no reserve or dedicated multicast link and broadcast link Test with MANET Routing(employs several multihop routing protocol, and packet queueing and enqueuing) with high data rate transmission and with low packetper second we can evaluate data transmission exactly through AWGN Channel and AWWN+Rayleigh Channel Result: Received photo Sending photo E.Functional requirement of MANETs 1) Main function: -MANETs is network that has seft-setup and be adaptive(tính tự thiết lập dễ thích nghi).All nodes of network can moving make topology structure of network change, but network nodes can detect the appearance of other one and process the connection to transmiss information without management of host station or control devices.Noticed that, besides detecting the connection of devices, it can types of device and respective description of this connected devices(laptop, PDA or smartphone,….) so the calculating, storing, data transmission of each node is also different when compared these nodes.Specially, routing problems is very important because it is effect on MANET’s efficiency 2) In real life -Military field -Commerical filed -Internal network -Personal Area Network(PAN) -Industrlize -Health care -Searching and aid(tìm kiếm viện trợ) -Educational Curriculum II) TECHNICAL CHARACTERISTIC OF MANETs *Functional Characteristic: 1)Autonomous terminal(thiết bị tự trị đầu cuối): In MANETs, each end pointmobile devices is self-control node(node tự trị) It can own function of host(máy chủ) and router(định tuyến) 2)Distributed operation(Phân chia hoạt động): All node of network have good combination to each other, so it is easier for observing and manage to distribute to start-end point(thiết bị đầu cuối) 3)Multihop router(định tuyến đa lường): Based on different attribute connection can set router on hop or multihop over wirless communication range(phạm vi truyền tải khơng dây) 4)Dynamic network topology(cấu hình động): Because all nodes are mobile nodes, so structure of network is easily change, so MANETs will routers adapting and condition of propagation like mobile sample and mobile node.Thus, not only MANETs can operate inside mobile network but also it can access to public network(Internet) 5)Fluctuating link capacity(dao động lượng liên kết): High bit error of propagion is notice to MANETs network since inteference, multipath effects and its effect is less than ethernet channel(mạng có dây) 6)Light-weight terminals(tối ưu hóa thiết bị dầu cuối): All node need to be optimized algorithms and operation *Classify based on function: 1)Flat MANETs(Mạng MANETs đẳng cấp) - Hierachical MANETs(Mạng MANETs phân cấp) +This is the most commonly used model In this model, the network is divided into domains, in each domain includes one or more clusters, each cluster is divided into many nodes There are two types of nodes, master node and normal node ++Master node: is the node that administers a router that is responsible for transferring data from nodes in the cluster to other nodes in the cluster and vice versa In other words, it acts as a gateway ++Normal nodes: are nodes located in the same cluster It can connect to the nodes in the cluster or connect to other clusters through the master node +With mechanisms on the network to use bandwidth resources more efficiently because messages only have to be transmitted in cluster However, managing node mobility becomes more complex The hierarchical network architecture is suitable for networks with low mobility Hierachical MANETs Model - Aggregate MANETs(Mạng MANETs kết hợp) +Network = Zones, Zone = nodes +Each node consists of two topology levels: low-level topology (node level), and high-level topology (zone level) +Each node is characterized by: node ID and zone ID In a Zone can apply hierarchical architecture or hierarchical architecture Aggregate MANETs Models 2)Classify based on protocol: -Signal-hop: The singal-hop routing Manet network is the simplest type of adhoc network model In it, all nodes are in the same coverage area, that is, nodes can connect directly to each other without the need for intermediate nodes Signal-hop Model -Multihop: Nodes can route with other nodes through intermediate nodes in the network In order for this model to work properly, a routing protocol that is compatible with the MANET network model is required Multihop Model -Mobie-multihop: This model is similar to the second model, but the difference here is that this model focuses on real-time applications such as audio, video Mobile-multihop Model *Connection type and working mechanism: 1)Network topology connection types -Mobile server network: in this topology, devices are only linked to a single server The network has inhomogeneous mobile devices -The network has inhomogeneous mobile devices: in this topology, machines can link directly to each other within their coverage area 2) Operation mode -IEEE-ad hoc mode: In this mode, mobile nodes communicate directly with each other without the need for any infrastructure In this mode, links can not be made over multiple hops -Infrastructure mode: In this mode, the network includes fixed AP access points and mobile nodes participating in the network, performing communication through the access points In this mode, links can be made over multiple hops J.RAYLEIGH FADING CHANNEL Rayleigh fading model considers the fading is caused by multipath reception Rayleigh fading model assumes that the magnitude of a signal that has passed through transmission medium will vary randomly according to a Rayleigh distribution There are many objects in the environment that scatter the radio signal before it arrives at the receiver and no dominant LOS propagation between the transmitter and receiver Gaussian PDF of Rayleigh Fading Channel _Rayleigh model= scatter signal+reflected signal My implemented code and results is same zip.file with my report for this progress VI) IMAGE TRANSMISSION THROUGH WIRELESS CHANNEL (IMPLEMENT ON JUPYTER NOTEBOOK) A)SCHEMATIC OF SYSTEM B)EACH PART OF DESIGN 1)QPSK: _QPSK has twice bandwidth efficiency of BPSK since two bits are transmitted in a single modulation _The phase of the carrier takes on one of for equally spaced value such as π/4, 3π/4 ,5π/4 ,7π/4, where each value of phase corresponds to unique pair of message bits QPSK Transmitter QPSK Receiver *QPSK modulator and demodulator : QPSK modulation output => [0, 3, 1, 2, 0, 3, 2, 1] *In our design: -First, we open image and convert it to input image and open it with gray scale to evaluate filter: Input image Const QPSK modulation -QPSK real and imaginary plot: Output of first stage -Encoding bit symbol by QPSK modulation and get the result: -Generate nosie of transmitter interference: *Overview of Gaussian Noise Channel: Mutual information over an AWGN channel for different input distributions Simulated symbol error rate performance of M-PSK modulation over AWGN channel Given a specific SNR point to simulate, we wish to generate a white Gaussian noise vector of appropriate strength and add it to the incoming signal The method described can be applied for both waveform simulations and the complex baseband simulations.SNR (γ) refers to γb = Eb/N0 when the modulation is of binary type (example: BPSK) For multilevel modulations such as QPSK and MQAM, the term SNR refers to γs = Es/N0 Simplified simulation model for awgn channel Complete simulation model for a communication system with AWGN channel -Get the modulated data stream by modulated the encoded symbol array 2)Capsulate modulated data for packets to transmit: -The data will be sent in packets which are small chuck of data sliced from the original data we want to send -The packets we are going to create will consist of two main part: header and payload( the data that we want to send) -Packets my images capsulated: 11685 3)Sending packing, receiving packets and equalizing them We use MMSE equalizer since: -It is linear equalizer -Its function to minimize the difference(error) between modulated signal data at previous stage and output signal of equalizer -Can evaluate the transmission coefficient of channel based on autocorrelation and correlation -Modulated header data: [-0.71+0.71j -0.71+0.71j 0.71-0.71j -0.71-0.71j -0.71-0.71j -0.71-0.71j -0.71-0 71j 0.71-0.71j] -Error: 4)Take the transmitted image and get ideal ouput: 6)Actual output of transmission(so much nosie at received image, test with another image with small size the ignore out of index of image after transmitted): 6)Evaluate output(ideal) by histogram equalizer: *Note use some filter for output after QPSK modulator: VII) EVALUATE IMAGE TRANSMISSION OF MANETs NETWORK AND WIRELESS CHANNEL A.MANETs network: -Mobile wireless networks are generally open to various attacks, such as information and physical security attacks than fixed wired networks Securing wireless ad hoc networks is particularly more difficult for many of the reasons such as: vulnerability of channels and nodes, absence of infrastructure, dynamically changing topology and etc The wireless channel is accessible to both legitimate network users and malicious attackers The abstract of centralized management makes the classical security solutions reliable on certification authorities and online servers not applicable A malicious attacker can rapidly become a router and break network operations by deliberately not following the protocol specifications -In Mobile ad-hoc network In order for a node to transmit a message to a node that is out of its radio range, the cooperation of other nodes in the network is required; this is called as multi-hop communication Therefore, each node at the same time must act both as a host and as a router as well b)Wireless channel -In order to transmit an image through a wireless channel various characteristics such as reduced propagation time, less power consumption and higher bit rate with an efficient bandwidth are required for a better image transmission The bandwidth restriction of wireless channel demands to reduce the data size of transmitted image Reduction of image data size is termed as image compression, therefore image to be represented in compact format -Developing an efficient wireless communication system for image and video signals other than voice signal is the need for a mobile radio link Image transmission through a wireless channel requires an image to be compatible with the channel characteristics such as bandwidth The image and video signals occupies a large space in storage device and takes long time to transmit over a wireless channel Compression techniques are used to reduce the redundant data from an acquired image and make it compatible with channel bandwidth In this paper various compression techniques and communication models are analyzed Various noises introduced during image acquisition and in channel These noises are required to be reduced during image formatting and de-formatting process at transmitter and receiver respectively ...TABLE OF CONTENTS I) Overview of our project II) Technical characteristic of MANETs III) Routing of MANETs IV) Implement MANETs on NS3 V) Wireless channel VI) Image transmission through wireless channel( implementation... better image transmission The bandwidth restriction of wireless channel demands to reduce the data size of transmitted image Reduction of image data size is termed as image compression, therefore image... in compact format -Developing an efficient wireless communication system for image and video signals other than voice signal is the need for a mobile radio link Image transmission through a wireless