Wi-Fi access point discovery system for mobile users

Abstract The continued increase in several mobile applications forces to replace existing limited spectrum indoor radio frequency wireless connections with high-speed ones. Visible light communications (VLC) technology has gained prominence in the development of high data rate transmission for fifth-generation networks. In optical wireless communications, light-emitting diode (LED) transmitters are used in applications that desire mobility as LED divergence enables larger coverage. Since each VLC access point covers a small area, handovers of mobile users are inevitable. Wavelength division multiplexing (WDM) can be used in VLC systems to tackle the above issue and to meet the increasing demand for indoor connectivity with high bit rates. In this paper, a new system architecture for WDM with coded modulated optical in orthogonal frequency division multiplexing (OFDM) VLC system in conjunction with red, green, blue, and yellow (RGBY) LEDs is proposed to reduce the impact of random receiver orientation of indoor mobile users over VLC downlink channels and improves the system’s bit-error-rate (BER) performance. Simulation results show that the proposed method is not affected by the user’s mobility and hence it performs better than other approaches, in terms of BER for all scenarios and at all positions. This study reveals that using WDM-OFDM-VLC with RGBY LEDs to construct a VLC system is very promising.

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Minimizing The Number of Channel Switches of Mobile Users in Cognitive Radio Ad-Hoc Networks

Journal of Sensor and Actuator Networks ◽

10.3390/jsan9020023 ◽

2020 ◽

Vol 9 (2) ◽

pp. 23 ◽

Cited By ~ 1

Author(s):

Rajorshi Biswas ◽

Jie Wu

Keyword(s):

Cognitive Radio ◽

Ad Hoc Networks ◽

Ad Hoc ◽

Path Loss ◽

Access Point ◽

Primary User ◽

Mobile Users ◽

Mobility Patterns ◽

Current Channel ◽

Hoc Networks

Cognitive radio (CR) technology is envisioned to use wireless spectrum opportunistically when the primary user (PU) is not using it. In cognitive radio ad-hoc networks (CRAHNs), the mobile users form a distributed multi-hop network using the unused spectrum. The qualities of the channels are different in different locations. When a user moves from one place to another, it needs to switch the channel to maintain the quality-of-service (QoS) required by different applications. The QoS of a channel depends on the amount of usage. A user can select the channels that meet the QoS requirement during its movement. In this paper, we study the mobility patterns of users, predict their next locations and probabilities to move there based on its history. We extract the mobility patterns from each user’s location history and match the recent trajectory with the patterns to find future locations. We construct a spectrum database using Wi-Fi access point location data and the free space path loss formula. We propose a machine learning-based mechanism to predict spectrum status of some missing locations in the spectrum database. We formulate a problem to select the current channel in order to minimize the total number of channel switches during a certain number of next moves of a user. We conduct an extensive simulation combining real and synthetic datasets to support our model.

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Seamless LTE Wi-Fi Architecture for LTE with Efficient UE Authentication

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.d1129.029420 ◽

2020 ◽

Vol 9 (4) ◽

pp. 329-334

Keyword(s):

Negative Impact ◽

Heavy Traffic ◽

Access Network ◽

Mobile Network ◽

Access Point ◽

Mobile Users ◽

Area Network ◽

Network Access ◽

Metropolitan Area Network ◽

Zone Control

Due to heavy demand of data uses and exponential increase in mobile users mobile network is suffering from heavy traffic overload in the metropolitan area network. Therefore, due to congestion as well as network overload mobile users are experiencing coverage issues such as latency, network access and very low throughput. At present network operators are actually capping data usages and throttling in speed of connection have very negative impact on satisfaction of mobile users. In such a scenario alternate solutions are expected like access point (AP) based network can be used as a complementary network. In this paper we have proposed a seamless LTE-Wi-Fi architecture by using packet gateway in LTE and Wi-Fi for maintaining the seamless connectivity for users and Wi-Fi is used as a complementary network over LTE. This proposed architecture has ANQP-DS (Access network query protocol Data Server) and AZC (Access Zone Control) are two main components to Wi-Fi network for balancing and controlling the load of User equipment’s (UE) in between access points (AP). It can used as one of the mechanism in the LTE and Wi-Fi Integration Process.

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