scholarly journals Analisis Pengaruh Interferensi Frekuensi Terhadap Kinerja Access Point Dengan Teknologi IEEE 802.11n

2019 ◽  
Vol 1 (2) ◽  
Author(s):  
Suri Darmiantini ◽  
I Wayan Agus Arimbawa ◽  
Andy Hidayat Jatmika
Keyword(s):  
Frequency Band ◽  
Packet Loss ◽  
Communication System ◽  
Local Area Network ◽  
Access Point ◽  
Wireless Channel ◽  
Area Network ◽  
Coverage Area ◽  
Ieee 802.11N ◽  
Network Quality

Technologies that support wireless networks include WLAN (Wireless Local Area Network) and WPAN (Wireless Personal Area Network). One of the most widely used WLAN products today is IEEE 802.11n while the WPAN application is Bluetooth. Using the same frequency band in a coverage area can cause interference. Interference that occurs can be caused due to the use of 2 pieces of the same communication system, as well as different in a region. This study aims to determine how much influence interference has on the decline in the quality of a communication system with parameters measuring bandwidth, jitter, and packet loss. From the results of measurements and analysis shows that network quality is affected due to interference. Where if the network is free from interference around it, the network quality will be better, if the network experiences interference because using the same frequency band in the same coverage area can affect network quality such as reduced bandwidth value, increased jitter, and packet loss as well as channel usage and different channels. And the closer the distance of the access point that uses a different channel in a coverage area will cause the decreasing bandwidth value to increase the value of jitter and packet loss and vice versa. Keywords: interference, wireless, channel, bandwidth, jitter, packet loss.

scholarly journals The concept of Virtual Contention Window for 802.11 IBSS wireless local area network mathematic modeling

2012 ◽  
Vol 16 (6) ◽  
pp. 39-45
Author(s):  
A.V. Lazebnyi ◽  
Volodymyr Semenovych Lazebnyi
Keyword(s):  
Packet Loss ◽  
Wireless Lan ◽  
Wireless Local Area Network ◽  
Local Area Network ◽  
Local Area ◽  
Wireless Channel ◽  
Contention Window ◽  
Transmission Time ◽  
Area Network ◽  
Mathematic Modeling

The concept of a virtual contention window for assessment of temporal and probabilistic characteristics of the processes occurring in the wireless LAN 802.11 is considered. The relations for determining the transmission time delay of the data package, the uneven of transmission time, throughput of wireless channel, the probability of packet loss for networks with saturated load are proposed in this paper.

scholarly journals ANALISIS PENGARUH JUMLAH CLIENT DAN JARAK CAKUPAN WIRELESS AP IEEE 802.11 N TERHADAP KUALITAS JARINGAN WLAN MENGGUNAKAN TEKNIK UR DAN WDS

2018 ◽  
Vol 2 (1) ◽  
Author(s):  
Ilmiatul Hafazah ◽  
I Wayan Agus Arimbawa ◽  
Andy Hidayat Jatmika
Keyword(s):  
Ieee 802.11 ◽  
Packet Loss ◽  
Distribution System ◽  
Wireless Local Area Network ◽  
Local Area Network ◽  
Local Area ◽  
Area Network ◽  
Ieee 802.11N

Standar jaringan WLAN yang paling banyak beredar dipasaran saat ini adalah IEEE 802.11n. Untuk membangun jaringan WLAN yang lebih praktis dapat menggunakan teknik UR dan WDS.  Penelitian ini bertujuan untuk dapat mengukur dan menganalisa pengaruh jumlah client dan jarak terhadap kualitas jaringan WLAN yang menggunakan teknik UR dan WDS dengan parameter ukur bandwidth, jitter, dan packet loss. Hasil analisa data diketahui bahwa semakin banyak client dan semakin jauh jarak transmisi dapat menurunkan kualitas jaringan UR dan WDS. Kualitas jaringan terbaik dihasilkan jaringan UR pada jarak 7,5m dengan rata-rata bandwidth sebesar 11934.7035 Kbps, rata-rata jitter sebesar 2.3563135 ms, dan rata-rata packet loss sebesar 1.90% dibandingkan jaringan WDS dengan rata-rata bandwidth 3846.9135 Kbps, rata-rata jitter 9.496095 ms, dan rata-rata packet loss 5.23%. Kualitas jaringan terburuk dihasilkan jaringan WDS pada jarak 30m dengan rata-rata bandwidth sebesar 898.32735 Kbps, rata-rata jitter sebesar 37.32591 ms, dan rata-rata packet loss sebesar 47.10% dibandingkan jaringan UR dengan rata-rata bandwidth 8859.797 Kbps, rata-rata jitter 13.082195 ms, dan rata-rata packet loss 19.24%. Hasil keseluruhan pengukuran diketahui bahwa teknik UR lebih unggul dibandingkan WDS dalam membangun jaringan WLAN.   KATA KUNCI : WLAN (Wireless Local Area Network), UR (Universar Repeater), WDS (Wireless Distribution System), Bandwidth, Jitter, Packet Loss

Distributed Generation Communications Utilizing a Real-time FPGA-based Channel Simulator in the ISM Frequency Band

2007 ◽  
Vol 8 (1) ◽  
Author(s):  
Julian Meng ◽  
Shane Barnes
Keyword(s):  
Distributed Generation ◽  
Frequency Band ◽  
Communication System ◽  
Local Area Network ◽  
Low Cost ◽  
Additive White Gaussian Noise ◽  
Area Network ◽  
Centralized Control ◽  
Wide Area Network ◽  
Channel Simulator

Deregulation of the power industry, increases in consumer demand of electricity and mandates to reduce greenhouse gases has significantly heightened the interest in distributed generation (DG). Typical DG sources include wind turbines, fuel cells, micro gas/diesel turbines, small hydro generators and photovoltaics. Currently most of these generation sources are optimized for local operation and thus the potential of DG that is both dispatchable and cost-effective has yet to be fully realized. One key technical challenge is the development of low-cost communications for remote telemetry and control of individual DG sources. Along with cost, other key communication system requirements are modularity, range and reliability. This paper presents a distributed generation communication system (DGCS) that is based on a wide area network (WAN) and local area network (LAN) topology and utilizes two variants of low-cost radio modems (RM) to satisfy the desired connectivity between the DG sites and a centralized control center. For the LAN, low-cost RMs operating in the industrial, scientific, and medical (ISM) frequency band offers point-to-multipoint scalability to multiple DG sites within a limited range. Integration of the ISM RMs with a cellular RM provides connectivity to a WAN or Internet thus providing long-range access to DG sites from any facility that has internet-access. Given the LAN scalability requirement, an ISM field programmable gate array (FPGA) channel simulator was developed to assess DGCS performance using channel impairments such as free-space path loss, multipath reflections, additive white Gaussian noise (AWGN), multiple access interference, and narrowband interference. This study provides the evaluation of two commercially available ISM radio modems and recommendations are made based on LAN requirements such as cost and performance given difficult channel conditions.

Transmission Power Optimization of Concurrently Communicating Two Access Points in Wireless Local Area Network

2020 ◽  
Vol 11 (4) ◽  
pp. 1-25
Author(s):  
Hendy Briantoro ◽  
Nobuo Funabiki ◽  
Minoru Kuribayashi ◽  
Kwenga Ismael Munene ◽  
Rahardhita Widyatra Sudibyo ◽  
...  
Keyword(s):  
Wireless Local Area Network ◽  
Power Optimization ◽  
Local Area Network ◽  
Access Point ◽  
Local Area ◽  
Raspberry Pi ◽  
Area Network ◽  
Transmission Power ◽  
Wireless Internet ◽  
Coverage Area

Currently, the IEEE 802.11 wireless local-area network (WLAN) has been prevalent around the world due to the advantages of mobility, flexibility, and scalability. WLAN offers the wireless internet-access method through an access-point (AP) at homes, schools, or offices. When multiple APs are deployed in the network field, the proper transmission power of each AP is essential to improve the performance, considering the coverage area, transmission capacity, and interference. In this paper, the authors study the transmission power optimization of concurrently communicating two APs in WLAN. Based on extensive experiment results, the authors propose a method of selecting the best power for each AP from the signal-to-noise ratio (SNR) of receiving signal strength (RSS). For evaluations, the authors implemented the proposed method on the elastic WLAN system testbed using Raspberry Pi for APs and conducted experiments for nine network topologies in two buildings at Okayama University. The results show that the proposal always selects the best power in any topology.

scholarly journals Reduce the Handoff Failure by Implementing Two WLAN in Handoff Region

2019 ◽  
Vol 8 (2) ◽  
pp. 1350-1354
Keyword(s):  
Wireless Local Area Network ◽  
Local Area Network ◽  
Access Point ◽  
Local Area ◽  
Mobile Node ◽  
Base Station ◽  
Adjacent Cell ◽  
Area Network ◽  
Data Loss ◽  
Coverage Area

The problem of wireless communication is the handoff. That problem mainly shows in the urban area because limited number of Access Point (AP) and the Base Station (BS). Main problem occur when the Mobile Node (MN) are goes to out of the coverage area the MN need to make handoff because the current or old Base Station(BS) does not gives the supports. Effect of this problem is call disconnection or data loss. IEEE802.11 based wireless local area network (WLAN) are widely use to give the supports of personal or commercial basis. In the proposed work the WLAN are placed on the two adjacent cell and they are crossly connected to the BS. This WLAN are used as an AP and that AP are enhanced the signal strength of the region of handoff and increased the area of BS. This WLAN gives the services for the time of degradation until fond the new channel in the new BS or the inside of WLAN area. For this cause the failure of handoff are minimized.

scholarly journals ANALISIS TRANSFER RATE WIRELESS LOCAL AREA NETWORK DENGAN STANDAR IEEE 802.11A DAN IEEE 802.11G PADA KANAL LINE OF SIGHT

2016 ◽  
Vol 3 (1) ◽  
pp. 31-39
Author(s):  
F Ammar ◽  
Hanafi Hanafi
Keyword(s):  
Transfer Rate ◽  
Wireless Local Area Network ◽  
Local Area Network ◽  
Access Point ◽  
Local Area ◽  
Line Of Sight ◽  
Area Network ◽  
Ieee 802.11A ◽  
5 Ghz

WiFi bekerja pada band 2,4 GHz dan 5 GHz. Standar WiFi yang bekerja pada frekuensi ini antara lain IEEE802.11g dan IEEE802.11a. Pada penelitian ini dilakukan pengukuran terhadap transfer rate download dan upload data dengan standar IEEE802.11g dan IEEE802.11a. Pengukuran dilakukan pada kanal Line of Sight (LOS), menggunakan dua buah laptop yang dihubungkan dengan Access Point (AP) standar IEEE802.11g dan IEEE802.11a.  Hasil penelitian diperoleh, pada standar IEEE802.11g, transfer rate download dan upload data tertinggi 2.662,54.KB/s dan 2.549,60 KB/s, dan terendah 484,50.KB/s dan 477,40 KB/s, sedangkan pada standar IEEE802.11a, transfer rate download dan upload data tertinggi 8.104,68 KB/s dan 5.744,24 KB/s, dan terendah 872,24 KB/s dan 465,38.KB/s. Pada standar IEEE802.11g, transfer rate download dan upload data pada sinyal terendah hingga di bawah 35% dan 30%, dari transfer rate download dan upload data tertinggi. Pada standar IEEE802.11a, transfer rate download dan upload data pada kualitas sinyal terendah hingga di bawah 20% dan 30%, dari transfer rate download dan upload data tertinggi. Kemampuan transfer rate download data Standar IEEE802.11a, 2–3 kali lebih baik pada kondisi kualitas sinyal tertinggi, dan tidak lebih dari 2 kali pada kondisi kualitas sinyal terendah, dibandingkan kemampuan transfer rate download data standar IEEE802.11g. Kemampuan transfer rate upload data Standar IEEE802.11a, 1,4–3 kali lebih baik pada kondisi kualitas sinyal tertinggi, dan 1-3 kali lebih baik pada kondisi kualitas sinyal terendah, dibandingkan kemampuan transfer rate upload data standar IEEE802.11g.

scholarly journals Rancang Bangun Antena Yagi 2400 MHz Untuk Receiver Komunikasi WiFi

2021 ◽  
Vol 8 (2) ◽  
pp. 75-84
Author(s):  
Gusni Amini Siagian ◽  
Lindawati Lindawati ◽  
Sopian Soim
Keyword(s):  
Standing Wave ◽  
Wireless Local Area Network ◽  
Local Area Network ◽  
Access Point ◽  
Local Area ◽  
Area Network

Wireless Local area Network  (WLAN) suatu jaringan area lokal tanpa kabel yang menggunakan frekuensi radio sebagai media transmisinya. Dalam penelitian ini merancang sebuah jaringan wifi di Perumahan Dosen Politeknik Negeri Sriwijaya, yang pancaran wifinya dari kampus Politeknik Negeri Sriwijaya, sehingga Perumahan Dosen dapat mengakses wifi tanpa perlu datang ke kampus. Sebagai receiver komunikasi wifi diperlukan peranan antena dalam sistem komunikasi tanpa kabel (wireless) dengan jarak jauh, antena yang digunakan adalah antena yagi yang bekerja pada frekuensi 2400 MHz. Antena yagi dipilih karena sifatnya yang directional atau pola pancarannya yang terarah. Dalam perancangan antena yagi untuk ukuran reflector, driven, director dan balun dibantu dengan software yagi calculator serta disimulasikan dan diuji  menggunakan MMANA-GAL untuk menghasilkan parameter antena yang lebih akurat. Antena yagi ini kemudian akan dihubungkan dengan access point yang disetup sebagai client untuk menerima sinyal dari transmitter dan router sebagai proses routing agar user di Perumahan Dosen dapat mengakses wifi tersebut. Berdasarkan hasil pengujian MMANA-GAL antena yagi dengan frekuensi 2400 MHz, diperoleh Standing Wave Ratio (SWR) sebesar 1.16 dan Penguatan (Gain) sebesar 14,59 dB.  

scholarly journals Underground Coal Mine Fingerprint Positioning Based on the MA-VAP Method

Sensors ◽  
2020 ◽  
Vol 20 (18) ◽  
pp. 5401
Author(s):  
Mingzhi Song ◽  
Jiansheng Qian
Keyword(s):  
Real Time ◽  
Coal Mine ◽  
Wireless Local Area Network ◽  
Local Area Network ◽  
Access Point ◽  
Cumulative Distribution ◽  
Kernel Principal Component Analysis ◽  
Area Network ◽  
Positioning Accuracy ◽  
Access Points

The access points (APs) in a coal mine wireless local area network (WLAN) are generally sparsely distributed. It can, with difficulty, satisfy the basic requirements of the fingerprint positioning based on Wi-Fi. Currently, the effectiveness of positioning is ensured by deploying more APs in an underground tunnel, which significantly increases system cost. This problem can be solved by using the Virtual Access Point (VAP) method that introduces virtual access points (VAPs), which can be virtually arranged in any part of the positioning area without installing actual access points. The drawback of the VAP method is that the generated received signal strength (RSS) value of a VAP is calculated based on the mapping of RSS value from only one corresponding access point (AP). This drawback does not consider the correlation between different AP signals and the generated RSS value of a VAP, which makes the modeling of fingerprint samples and real-time RSS collection incomplete. This study proposed a Multi-Association Virtual Access Point (MA-VAP) method takes into account the influence of multi-association. The multi-association coefficient is calculated based on the correlation between the RSS values of a VAP and multiple access points (APs). Then, the RSS value generated by a VAP is calculated using the multi-association function. The real-time collected RSS values from multiple APs related to this VAP are the input of the multi-association function. The influence of the number of VAPs and their arrangement on positioning accuracy is also analyzed. The experimental positioning results show that the proposed MA-VAP method achieves better positioning performance than the VAP method for the same VAP arrangement. Combined with the Weight K-Nearest Neighbors (WKNN) algorithm and Kernel Principal Component Analysis (KPCA) algorithm, the positioning error of the MA-VAP method of the error distance cumulative distribution function (CDF) at 90% is 4.5 m (with WKNN) and 3.5 m (with KPCA) in the environment with non-line-of-sight (NLOS) interference, and the positioning accuracy is improved by 10% (with WKNN) and 22.2% (with KPCA) compared with the VAP method. The MA-VAP method not only effectively solves the fingerprint positioning problem when APs are sparse deployed, but also improves the positioning accuracy.

scholarly journals Unequal loss protection scheme using a quality prediction model in a Wi-Fi broadcasting system

2019 ◽  
Vol 15 (6) ◽  
pp. 155014771985424
Author(s):  
Dong Hyun Kim ◽  
Jong Deok Kim
Keyword(s):  
Packet Loss ◽  
Forward Error Correction ◽  
Wireless Local Area Network ◽  
Local Area Network ◽  
Local Area ◽  
Multimedia Data ◽  
Area Network ◽  
Broadcasting System ◽  
Forward Error ◽  
Unequal Loss Protection

Wireless local area network–based broadcasting techniques are a type of mobile Internet Protocol television technology that simultaneously transmits multimedia content to local users. Contrary to the existing wireless local area network–based multimedia transmission systems, which transmit multimedia data to users using unicast packets, a wireless local area network–based broadcasting system is able to transmit multimedia data to many users in a single broadcast packet. Consequently, network resources do not increase with the increase in the number of users. However, IEEE 802.11 does not provide a packet loss recovery algorithm for broadcast packet loss, which is unavoidable. Therefore, the forward error correction technique is required to address the issue of broadcast packet loss. The broadcast packet loss rate of a wireless local area network–based broadcasting system that transmits compressed multimedia data is not proportional to the quality deterioration of the received video signals; therefore, it is difficult to predict the quality of the received video while also considering the effect of broadcast packet loss. In this scenario, allocating equal forward error correction packets to compressed frames is not an effective method for recovering broadcast packet loss. Thus, several studies on unequal loss protection have been conducted. This study proposes an effective, prediction-based unequal loss protection algorithm that can be applied to wireless local area network–based broadcasting systems. The proposed unequal loss protection algorithm adopts a novel approach by adding forward error correction packets to every transmission frame while considering frame loss. This algorithm was used as a new metric to predict video quality deterioration, and an unequal loss protection structure was designed, implemented, and verified. The effectiveness of the quality deterioration model and the validity of the unequal loss protection algorithm were demonstrated through experiments.

Sign in / Sign up

Export Citation Format

Share Document