Improved Preamble Detection and Round-Trip Delay Estimation for Random Access in High-Mobility Airborne Communication Systems

With the rapid development of high-mobility wireless communication systems, e.g., high-speed train (HST) and metro wireless communication systems, more and more attention has been paid to the wireless communication technology in tunnel-like scenarios. In this paper, we propose a three-dimensional (3D) nonstationary multiple-input multiple-output (MIMO) channel model with high-mobility wireless communication systems using leaky coaxial cable (LCX) inside a rectangular tunnel over the 1.8 GHz band. Taking into account single-bounce scattering under line-of-sight (LoS) and non-line-of-sight (NLoS) propagations condition, the analytical expressions of the channel impulse response (CIR) and temporal correlation function (T-CF) are derived. In the proposed channel model, it is assumed that a large number of scatterers are randomly distributed on the sidewall of the tunnel and the roof of the tunnel. We analyze the impact of various model parameters, including LCX spacing, time separation, movement velocity of Rx, and K-factor, on the T-CF of the MIMO channel model. For HST, the results of some further studies on the maximum speed of 360 km/h are given. By comparing the T-CF between the dipole MIMO system and the LCX-MIMO system, we can see that the performance of the LCX-MIMO system is better than that of the dipole MIMO system.

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An Improved Mobility Aware Relaying Scheme for Body Area Networks

10.36227/techrxiv.12141012.v1 ◽

2020 ◽

Author(s):

Costas Michaelides ◽

Maria Iloridou ◽

Foteini-Niovi Pavlidou

Keyword(s):

Random Access ◽

High Mobility ◽

Body Area Networks ◽

Ieee 802.15.6 ◽

Body Area ◽

Star Topology ◽

Packet Delivery ◽

Safety Regulations ◽

Simulation Results ◽

To Receive

Communication in Body Area Networks (BANs) involves weak signals, due to safety regulations, huge pathloss from the absorption and usually high mobility. In this work, we introduce an improved mobility aware relaying scheme for BANs, as an alternative to the two-hop star topology extension of IEEE 802.15.6-2012, in order to enhance packet delivery. Specifically, an emergency phase (EP) is added after the regular random access phase (RAP1) of the superframe and the connected nodes transmit rescue beacons to reach disconnected nodes. When a disconnected node receives a rescue beacon, it participates in the current EP. The packets are buffered and relayed to the hub by the connected nodes. Simulation results show that it is feasible to receive more packets compared to the standard with a justified increase of energy consumption due to random access which is compensated with increased packet delivery.

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Future M2M Communication Networks

Advances in Wireless Technologies and Telecommunication - Handbook of Research on Next Generation Mobile Communication Systems ◽

10.4018/978-1-4666-8732-5.ch007 ◽

2016 ◽

pp. 149-178

Author(s):

Stavroula Vassaki ◽

George Pitsiladis ◽

Stavros E. Sagkriotis ◽

Athanasios D. Panagopoulos

Keyword(s):

Communication Networks ◽

Communication Systems ◽

Spectrum Sharing ◽

Random Access ◽

Wireless Communication Networks ◽

Lte Networks ◽

M2m Communication ◽

M2m Communications ◽

The Future ◽

4G Lte

Machine type communications (or Machine-to-Machine / M2M) communications have emerged as an important paradigm in wireless communication networks. The current M2M standardization activities are presented and their implementation in 4G/LTE networks is described in detail. The chapter is divided in three parts that are related to the evolution of the Future M2M communication Networks. The first part focuses on existing random access management schemes for M2M communications that are presented in the literature. The second part is devoted on spectrum sharing methods and on M2M clustering and it presents the spatial distribution of heterogeneous networks and its impact on their connectivity. Finally, the last part refers to energy efficiency issues of the future M2M communication systems and their implementation using distributed power control and MAC/scheduling algorithms.

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At Sensor Diagnosis for Smart Healthcare

International Journal of Advanced Pervasive and Ubiquitous Computing ◽

10.4018/ijapuc.2018100101 ◽

2018 ◽

Vol 10 (4) ◽

pp. 1-13

Author(s):

Chetna Laroiya ◽

Vijay Bhushan Aggarwal

Keyword(s):

Joint Probability ◽

Sliding Window ◽

Communication Technologies ◽

Data Streaming ◽

Round Trip ◽

Time Data ◽

Smart Healthcare ◽

Body Sensors ◽

Round Trip Delay

In order to implement IoT-based health-care for improved quality of life, we have to deal with sensor and communication technologies. In this article, the authors propose an approach to analyse real-time data streaming from a patient's surface body sensors, which are to be looked upon in a small sliding window frame. Time series analysis of data from the sensors is effective in reducing the round-trip delay between patient and the medical server. Two algorithms are for the sensor, and odd measures are proposed based on joint probability and joint conditional probability. The proposed algorithms are to be SQL compliant, as traces of at-sensor UDBMS alongside elementary capabilities supports databases with a meagre amount of SQL, which is evident in the literature.

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Methods for mutual time delay estimation of wideband signals based on nonlinear digital filtering

ITM Web of Conferences ◽

10.1051/itmconf/20193003008 ◽

2019 ◽

Vol 30 ◽

pp. 03008

Author(s):

Roman Ershov ◽

Oleg Morozov

Keyword(s):

Time Delay ◽

Communication Systems ◽

Satellite Communication ◽

Signal To Noise Ratio ◽

Digital Filtering ◽

Time Delay Estimation ◽

Delay Estimation ◽

Wideband Signals ◽

Correlation Processing

Methods for mutual time delay estimation of wideband signals propagating in satellite communication systems are proposed. The signals are propagated in different channels and received with low signal-to-noise ratio. A characteristic feature of satellite channel is the presence of the Doppler Effect, which leads to a shift and scaling the signal spectrums. The proposed approaches are based on the separation of narrow-band channels from the studied signals, using non-linear digital filtering algorithms in each channel, and subsequent optimal (correlation) processing. The accuracy of the proposed methods and the reliability of the determination of time delay are investigated.

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