4 research outputs found

    Design of information hiding algorithm for multi-link network transmission channel

    Get PDF
    Traditional channel information hiding algorithms based on m-sequence for multi-link network transmission, which apply m-sequence to channel coding information hiding system, do not analyze the upper limit of hiding capacity of multi-link network transmission channel system, and do not consider the hidden danger of overlapping secret information when embedding secret information is too large. It has the defects of low efficiency, poor accuracy and large storage cost. This paper designs an information hiding algorithm for multi-link network transmission channel based on secondary positioning, it uses RS code M public key cryptosystem to pre-process secret information and improve the security of information; calculates the upper limit of hiding capacity of multi-link network transmission channel system through information hiding capacity analysis model, and determines whether the hiding capacity exceeds the secret information. Secondary location and cyclic shift mechanism are introduced to improve the randomness of location selection and avoid overlapping of secret information. The experimental results show that the proposed algorithm has a great advantage in memory cost. When the channel SNR is 0 dB and 8 dB, the normalization coefficients are 0.87 and 1.04, respectively. This shows that the algorithm has a high accuracy in extracting secret information. The average time spent on hiding information is 2.04 s, indicating that the algorithm has high information hiding rate and storage efficiency

    Cooperative Routing in Multi-Radio Multi-Hop Wireless Network

    Get PDF
    There are many recent interests on cooperative communication (CC) in wireless networks. Despite the large capacity gain of CC in small wireless networks, CC can result in severe interference in large networks and even degraded throughput. The aim of this chapter is to concurrently exploit multi-radio and multi-channel (MRMC) and CC technique to combat co-channel interference and improve the performance of multi-hop wireless network. Our proposed solution concurrently considers cooperative routing, channel assignment, and relay selection and takes advantage of both MRMC technique and spatial diversity to improve the throughput. We propose two important metrics, contention-aware channel utilization routing metric (CACU) to capture the interference cost from both direct and cooperative transmission, and traffic aware channel condition metric (TACC) to evaluate the channel load condition. Based on these metrics, we propose three algorithms for interference-aware cooperative routing, local channel adjustment, and local path and relay adaptation, respectively, to ensure high-performance communications in dynamic wireless networks. Our algorithms are fully distributed and can effectively mitigate co-channel interference and achieve cooperative diversity gain. To our best knowledge, this is the first distributed solution that supports CC in MRMC networks. Our performance studies demonstrate that our algorithms can significantly increase the aggregate throughput

    Interference Mitigation Based on Radio Aware Channel Assignment for Wireless Mesh Networks

    Get PDF
    © 2018, Springer Science+Business Media, LLC, part of Springer Nature. An intricate network deployment for high demand users leads to simultaneous transmission in wireless mesh networks. Multiple radios are adapted to individual nodes for improving network performance and Quality of Service (QoS). However, whenever multiple radios are assigned to the same channel, co-located radio interference occurs, which poses a major drawback. This paper proposes a Radio aware Channel Assignment (Ra-CA) mechanism based on a direct graphical model for mitigation of interference in multi-radio multi-channel networks. Initially, the co-located radio interference is identified by classifying non-interfering links for simultaneous transmission in the network. Proposed channel assignment mechanism helps in allocating the minimal number of channels to the network that mitigate co-located radio interference. Performance analysis of the proposed Ra-CA strategy is carried out compared with other existing techniques, like Breadth First Search-Channel Assignment (BFS-CA) and Maximal Independent Set Channel Assignment (MaIS-CA), in multi-radio networks. Simulation results demonstrate that the proposed channel assignment scheme is more efficient compared to the existing ones, in terms of QoS parameters like, packet drop rate, packet delivery ratio, transmission delay and throughput

    Архітектура автоматизованих систем на основі mesh-мереж

    Get PDF
    Мета роботи полягає у вивченні принципів роботи та особливостей реалізації розподілених безпровідних мереж на базі стандартних протоколів зв’язку; Реалізації функціоналу розподіленої mesh-мережі на базі апаратних мікроконтролерних пристроїв, які працюють за стандартним безпровідним протоколом Wi-Fi. У роботі розглянуто найбільш популярні безпровідні протоколи зв’язку, та особливості їх застосування при розгортанні mesh-мереж, показано їх основні переваги, недоліки та проаналізовано відмінності. У результаті проведених досліджень встановлено, що для використання в масштабах невеликих мереж доцільно використовувати пристрої з підтримкою протоколу Wi-Fi, оскільки він характеризується достатньою надійністю та захищеністю, а пристрої із його підтримкою широко розповсюджені і відносно простоті у налаштуванні. Описано теоретичні аспекти розповсюдження радіохвиль у частотному діапазоні 2,4 ГГц та зроблено оцінку ослаблення сигналу при проходженні через перешкоди плоскої конфігурації (стіни будівель). На основі мікроконтроолерного модуля ESP-8266 було реалізовано вузол mesh-мережі з передачею даних через віддалений сервер MQTT брокер. Описано функціональні можливості та можливі області застосування компонентів розподіленої безпровідної мережі
    corecore