scholarly journals Link Recovery Scheme for Multi-Point mmWave Communications

Electronics ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 50
Author(s):  
Adel Aldalbahi
Keyword(s):  
Mobile Station ◽  
Base Station ◽  
Fast Recovery ◽  
Link Failures ◽  
Access Scheme ◽  
Directional Transmission ◽  
Recovery Scheme ◽  
Recovery Times ◽  
Efficient Power ◽  
Recovery Schemes

Directional transmission in millimeter wave (mmWave) communications results in prolonged access times. This is attributed to the increased number of conducted measurements to determine optimum beam directions at the mobile station (MS) and base station (BS) that return the highest received signal levels. Additionally, once these beams are determined and links are established for data-planes, then blockage effects and outages make these links more vulnerable to link failures, resulting in communications drops. Hence, dynamic and fast recovery schemes are required to maintain communications sessions following the beam access stage. In this paper, a novel recovery access scheme is proposed for multi-point mmWave communications based on fog access points (AP). Namely, the scheme leverages diversity and network coding techniques to achieve near-instantaneous recovery times, without the need for beam scanning. The scheme features near-instantaneous data recovery times and efficient power consumption as compared to traditional recovery methods.

scholarly journals Multi-Backup Beams for Instantaneous Link Recovery in mmWave Communications

Electronics ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 1145 ◽  
Author(s):  
Adel Aldalbahi
Keyword(s):  
Antenna Arrays ◽  
Mobile Station ◽  
Base Station ◽  
Main Beam ◽  
Spatial Direction ◽  
Multiple Beams ◽  
Beamformer Design ◽  
Recovery Scheme ◽  
Recovery Times ◽  
Millimeter Wave Communications

In this paper, a novel link recover scheme is proposed for standalone (SA) millimeter wave communications. Once the main beam between the base station (BS) and the mobile station (MS) is blocked, then a bundle-beam is radiated that covers the spatial direction of the blocked beam. These beams are generated from an analog beamformer design that is composed of parallel adjacent antenna arrays to radiate multiple simultaneous beams, thus creating an analog beamformer of multiple beams. The proposed recovery scheme features instantaneous recovery times, without the need for beam scanning to search for alternative beam directions. Hence, the scheme features reduced recovery times and latencies, as opposed to existing methods.

scholarly journals BRNN-LSTM for Initial Access in Millimeter Wave Communications

Electronics ◽  
2021 ◽  
Vol 10 (13) ◽  
pp. 1505
Author(s):  
Adel Aldalbahi ◽  
Farzad Shahabi ◽  
Mohammed Jasim
Keyword(s):  
Millimeter Wave ◽  
Short Term Memory ◽  
Mobile Station ◽  
Base Station ◽  
Time Step ◽  
Directional Transmission ◽  
Long Short Term Memory ◽  
Power And Energy ◽  
Learning Schemes ◽  
Millimeter Wave Communications

The use of beamforming technology in standalone (SA) millimeter wave communications results in directional transmission and reception modes at the mobile station (MS) and base station (BS). This results in initial beam access challenges, since the MS and BS are now compelled to perform spatial search to determine the best beam directions that return highest signal levels. The high number of signal measurements here prolongs access times and latencies, as well as increasing power and energy consumption. Hence this paper proposes a first study on leveraging deep learning schemes to simplify the beam access procedure in standalone mmWave networks. The proposed scheme combines bidirectional recurrent neural network (BRNN) and long short-term memory (LSTM) to achieve fast initial access times. Namely, the scheme predicts the best beam index for use in the next time step once a MS accesses the network, e.g., transition from sleep to active (or idle) modes. The scheme eliminates the need for beam scanning, thereby achieving ultra-low access times and energy efficiencies as compared to existing methods.

Fast retransmit and fast recovery schemes of transport protocols: A survey and taxonomy

2008 ◽  
Vol 52 (6) ◽  
pp. 1308-1327 ◽  
Author(s):  
Cheng-Yuan Ho ◽  
Yaw-Chung Chen ◽  
Yi-Cheng Chan ◽  
Cheng-Yun Ho
Keyword(s):  
Transport Protocols ◽  
Fast Recovery ◽  
Recovery Schemes

Reparo: A Fast RAID Recovery Scheme for Ultra-large SSDs

2021 ◽  
Vol 17 (3) ◽  
pp. 1-24
Author(s):  
Duwon Hong ◽  
Keonsoo Ha ◽  
Minseok Ko ◽  
Myoungjun Chun ◽  
Yoona Kim ◽  
...  
Keyword(s):  
Storage Systems ◽  
Storage System ◽  
Experimental Results ◽  
Huge Amount ◽  
Failure Characteristics ◽  
System A ◽  
Recovery Scheme ◽  
Cost Efficient ◽  
Recovery Schemes ◽  
Multi Core Processor

A recent ultra-large SSD (e.g., a 32-TB SSD) provides many benefits in building cost-efficient enterprise storage systems. Owing to its large capacity, however, when such SSDs fail in a RAID storage system, a long rebuild overhead is inevitable for RAID reconstruction that requires a huge amount of data copies among SSDs. Motivated by modern SSD failure characteristics, we propose a new recovery scheme, called reparo , for a RAID storage system with ultra-large SSDs. Unlike existing RAID recovery schemes, reparo repairs a failed SSD at the NAND die granularity without replacing it with a new SSD, thus avoiding most of the inter-SSD data copies during a RAID recovery step. When a NAND die of an SSD fails, reparo exploits a multi-core processor of the SSD controller in identifying failed LBAs from the failed NAND die and recovering data from the failed LBAs. Furthermore, reparo ensures no negative post-recovery impact on the performance and lifetime of the repaired SSD. Experimental results using 32-TB enterprise SSDs show that reparo can recover from a NAND die failure about 57 times faster than the existing rebuild method while little degradation on the SSD performance and lifetime is observed after recovery.

A review on mmWave based energy efficient RoF system for next generation mobile communication and broadband systems

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Parvin Kumar ◽  
Sanjay Kumar Sharma ◽  
Shelly Singla ◽  
Varun Gupta ◽  
Abhishek Sharma
Keyword(s):  
Wireless Communication ◽  
Optical Fiber ◽  
Millimeter Wave ◽  
Mobile Communication ◽  
Energy Efficient ◽  
Mobile Station ◽  
Base Station ◽  
Electrical Signal ◽  
Next Generation ◽  
Efficient System

Abstract In today’s scenario, wireless communication is turning into a decisive and leading backbone to access the worldwide network. Therefore, the usage of mobile phones and broadband is rising staggeringly. To satisfy their expulsive needs, it demands increment in data rates while providing higher bandwidth and utilizing optical fiber in wireless communication, and this becomes a worldwide analysis area. Radio over fiber (RoF) system is taken into account as best solution to fulfill these needs. In RoF system, the radio frequency signal operated at millimeter wave (30–300 GHz) is centralized and processed at control station (CS) and also, the CS upconverts this electrical signal to optical domain. By employing optical fiber link, this signal reaches to base station (BS). Then, the received optical signal converts back to electrical domain at the respective BS. Now BS radiates the electrical signal to corresponding mobile station (MS) in commission with the millimeter wave frequency bands. This RoF system is providing massive bandwidth, facilitating large mobility for RF frequency signals, small loss, fast and cost effective setup, wonderful security, and unlicensed spectrum etc. The RoF system introduces microcells structure for BS cells to boost the frequency reuse and needed capacity. It has benefits in terms of ability to fulfill increasing bandwidth demands to cut back the power consumption and the dimensions of the handset devices. This paper firstly explains the overview of existing wireless mobile communication and broadband systems and then, targets the review of RoF system which will become energy efficient system for next generation mobile communication and future broadband systems. This paper also includes the performance degradation and evaluation parameters. Finally, this paper presents the various research opportunities for its implementation zone.

scholarly journals Energy-Efficient Power Allocation and Relay Selection Schemes for Relay-Assisted D2D Communications in 5G Wireless Networks

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 2865 ◽  
Author(s):  
Md Rahman ◽  
YoungDoo Lee ◽  
Insoo Koo
Keyword(s):  
Wireless Networks ◽  
Power Allocation ◽  
Relay Selection ◽  
Base Station ◽  
Data Rate ◽  
Transmission Power ◽  
D2d Communications ◽  
Long Distance ◽  
Inference System ◽  
Efficient Power

Device-to-device (D2D) communications allows user equipment (UE) that are in close proximity to communicate with each other directly without using a base station. Relay-assisted D2D (RA-D2D) communications in 5G networks can be applied to support long-distance users and to improve energy efficiency (EE) of the networks. In this paper, we first establish a multi-relay system model where the D2D UEs can communicate with each other by reusing only one cellular uplink resource. Then, we apply an adaptive neuro-fuzzy inference system (ANFIS) architecture to select the best D2D relay to forward D2D source information to the expected D2D destination. Efficient power allocation (PA) in the D2D source and the D2D relay are critical problems for operating such networks, since the data rate of the cellular uplink and the maximum transmission power of the system need to be satisfied. As is known, 5G wireless networks also aim for low energy consumption to better implement the Internet of Things (IoT). Consequently, in this paper, we also formulate a problem to find the optimal solutions for PA of the D2D source and the D2D relay in terms of maximizing the EE of RA-D2D communications to support applications in the emerging IoT. To solve the PA problems of RA-D2D communications, a particle swarm optimization algorithm is employed to maximize the EE of the RA-D2D communications while satisfying the transmission power constraints of the D2D users, minimum data rate of cellular uplink, and minimum signal-to-interference-plus-noise-ratio requirements of the D2D users. Simulation results reveal that the proposed relay selection and PA methods significantly improve EE more than existing schemes.

scholarly journals Design and Verification of Secure Mutual Authentication Protocols for Mobile Multihop Relay WiMAX Networks against Rogue Base/Relay Stations

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Jie Huang ◽  
Chin-Tser Huang
Keyword(s):  
Low Cost ◽  
Mutual Authentication ◽  
Mobile Station ◽  
Base Station ◽  
Authentication Protocols ◽  
Current Standard ◽  
Replay Attack ◽  
Wimax Networks ◽  
Main Challenge ◽  
Formal Tool

Mobile multihop relay (MMR) WiMAX networks have attracted lots of interest in the wireless communication industry recently because of its scalable coverage, improved data rates, and relatively low cost. However, security of MMR WiMAX networks is the main challenge to be addressed. In this paper, we first identify several possible attacks on MMR WiMAX networks in which a rogue base station (BS) or relay station (RS) can get authenticated and gain control over the connections and show that the current standard does not address this problem well. We then propose a set of new authentication protocols for protecting MMR WiMAX networks from rogue BS attack, rogue RS attack, and suppress-replay attack. Our protocols can provide centralized authentication by using a trusted authentication server to support mutual authentication between RS and BS, between RS and RS, and between mobile station (MS) and RS. Moreover, our protocols can also provide distributed authentication with a license issued by the trusted server. We use a formal tool called Scyther to analyze and verify the security properties of our protocols. The results show that our protocols can counter rogue BS and RS attacks and suppress-replay attack and are not susceptible to any known attacks.

Sign in / Sign up

Export Citation Format

Share Document