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Seungmo Kim

Bio: Seungmo Kim is an academic researcher from Georgia Southern University. The author has contributed to research in topics: Dedicated short-range communications & Radar. The author has an hindex of 11, co-authored 54 publications receiving 435 citations. Previous affiliations of Seungmo Kim include Virginia Tech & Information and Communications University.

Papers published on a yearly basis

Papers
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Journal ArticleDOI
TL;DR: An extensive study of the co-channel coexistence of 5G in two critical mmW bands, 27.5–28.35 GHz (28 GHz) and 71–76 GHz (70 GHz) bands, where fixed satellite service (FSS) and fixed service (FS), such as wireless backhaul, are the predominant incumbent users.
Abstract: A promising way of realizing the fifth generation (5G) wireless systems is to operate 5G deployments at higher frequency bands, specifically in the millimeter-wave (mmW) spectrum (30-300 GHz). Access to such spectrum bands will enable future 5G wireless systems to meet the 5G requirements of peak rate greater than 10 Gb/s, and cell edge rate of up to 1 Gb/s. However, the emerging 5G systems will need to coexist with a number of incumbent systems in these bands. This paper provides an extensive study of the co-channel coexistence of 5G in two critical mmW bands, 27.5-28.35 GHz (28 GHz) and 71-76 GHz (70 GHz) bands, where fixed satellite service (FSS) and fixed service (FS), such as wireless backhaul, are the predominant incumbent users. In the 28-GHz study, we show that interference from 5G into the FSS space stations can be kept below the FSS interference protection criterion. We also characterize the minimum separation distance between the FSS earth stations (ESs) and 5G in order to protect the 5G system from interference due to the ESs transmissions. In the 70-GHz study, we show that the 5G-to-FS interference could be a potential issue in certain scenarios, but we introduce techniques to significantly suppress this interference, while maintaining acceptable performance of the 5G systems. For each study, we suggest appropriate deployment strategies for a 5G system based on our results.

83 citations

Journal ArticleDOI
TL;DR: This paper provides an analysis framework that formulates the impact of mobility on a blockchain system’s performance in a VANET based on three key metrics: the probability of a successful addition of block to the chain; the stability of a rendezvous, and the number of blocks exchanged during a Rendezvous.
Abstract: This paper investigates how mobility affects the performance of a blockchain system operating in a vehicular ad hoc network (VANET). The mobility of nodes incurs a unique challenge to a blockchain system due to continuous change and dynamicity in the connectivity of the nodes. Specifically, the mobility makes a proof-of-work (PoW) process difficult since while moving the nodes can only have a limited length of time for a “rendezvous” to exchange a new block for verification. For this reason, accurate modeling for the block exchange behavior in a VANET is also challenging, which nevertheless has not been discussed in previous studies. Therefore, this paper provides an analysis framework that formulates the impact of mobility on a blockchain system's performance in a VANET based on three key metrics: (i) the probability of a successful addition of block to the chain; (ii) the stability of a rendezvous, and; (iii) the number of blocks exchanged during a rendezvous. The closed-form expressions and numerical results display the performance of a blockchain system in various scenarios in a VANET.

72 citations

Proceedings ArticleDOI
15 May 2008
TL;DR: It is shown that the proposed scenarios are able to achieve significant gains over a conventional cellular relay system in terms of the normalized system capacity, and relay combined with cognitive radio can be considered as a viable solution to get higher downlink capacity.
Abstract: In this paper, we propose two operating scenarios of employing cognitive radio to downlink of relay networks The first scenario uses ISM band while the second scenario exploits opportunity of channel use at UHF spectrum The capacity gain over conventional relay is investigated in terms of the normalized system capacity We first statistically model the spectrum usage pattern in those bands and derive the achievable data rate and outage probability in order to analyze performance gain in the view of practical system establishment Then, we define system capacity by normalizing the effect of bandwidth so that a fair comparison of performance is accomplished Through our analysis and simulations, it is shown that the proposed scenarios are able to achieve significant gains over a conventional cellular relay system in terms of the normalized system capacity As a result, relay combined with cognitive radio can be considered as a viable solution to get higher downlink capacity

25 citations

Patent
29 May 2008
TL;DR: In this article, a cognitive radio communication apparatus and method to control a sensing operation is presented. But it does not consider the control of the sensing period of the primary system, as in this paper.
Abstract: A cognitive radio communication apparatus and method to control a sensing operation. The cognitive radio communication apparatus includes an information receiver to receive channel state information associated with a channel occupancy state of a primary system from at least one sensing node of a secondary system; a sensing control unit to control a sensing period of the at least one sensing node according to a change pattern of the channel occupancy state, based on the channel state information; and a control information transmitter to transmit control information associated with the controlled sensing period to at least one member node of the secondary system.

21 citations

Journal ArticleDOI
TL;DR: In this article, a method that suppresses Wi-Fi-to-radar (WtR) interference is proposed, in which a WiFi transmitter (TX) is selected to avoid beam angles toward the victim radar.
Abstract: Coexistence between radar and outdoor wireless fidelity (Wi-Fi) needs thorough study since the IEEE 802.11 working group (WG) opposed the latest rules in 3550–3700 MHz (the 3.5 GHz band) that require “exclusion zones.” This letter proposes a method that suppresses Wi-Fi-to-radar (WtR) interference, in which a Wi-Fi transmitter (TX) is selected to avoid beam angles toward the victim radar. It is distinguished from prior schemes since it ensures that the Wi-Fi remains operable while suppressing the WtR interference.

18 citations


Cited by
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01 Jan 2016
TL;DR: An introduction to the theory of point processes is universally compatible with any devices to read and will help you get the most less latency time to download any of the authors' books like this one.
Abstract: Thank you for downloading an introduction to the theory of point processes. As you may know, people have search hundreds times for their chosen novels like this an introduction to the theory of point processes, but end up in infectious downloads. Rather than enjoying a good book with a cup of coffee in the afternoon, instead they juggled with some harmful virus inside their computer. an introduction to the theory of point processes is available in our digital library an online access to it is set as public so you can download it instantly. Our book servers hosts in multiple locations, allowing you to get the most less latency time to download any of our books like this one. Merely said, the an introduction to the theory of point processes is universally compatible with any devices to read.

903 citations

Journal ArticleDOI
TL;DR: It is shown that the outage probability of cognitive relay networks is higher than that of conventional relay networks due to the interference constraint, and the decrease in outage probability achieved by increasing the selection diversity is not less than that in conventional relay Networks.
Abstract: This paper evaluates the outage probability of cognitive relay networks with cooperation between secondary users based on the underlay approach, while adhering to the interference constraint on the primary user, i.e., the limited amount of interference which the primary user can tolerate. A relay selection criterion, suitable for cognitive relay networks, is provided, and using it, we derive the outage probability. It is shown that the outage probability of cognitive relay networks is higher than that of conventional relay networks due to the interference constraint, and we quantify the increase. In addition, the outage probability is affected by the distance ratio of the interference link (between the secondary transmitter and the primary receiver) to the relaying link (between the secondary transmitter and the secondary receiver). We also prove that cognitive relay networks achieve the same full selection diversity order as conventional relay networks, and that the decrease in outage probability achieved by increasing the selection diversity (the number of relays) is not less than that in conventional relay networks.

521 citations

Journal ArticleDOI
TL;DR: This work demonstrates that the proposed idea of tuning the block arrival rate is provably online and capable of driving the system dynamics to the desired operating point and identifies the improved dependency on other blockchain parameters for a given set of channel conditions, retransmission limits, and frame sizes.
Abstract: We propose an autonomous blockchain-based federated learning (BFL) design for privacy-aware and efficient vehicular communication networking, where local on-vehicle machine learning (oVML) model updates are exchanged and verified in a distributed fashion. BFL enables oVML without any centralized training data or coordination by utilizing the consensus mechanism of the blockchain. Relying on a renewal reward approach, we develop a mathematical framework that features the controllable network and BFL parameters (e.g., the retransmission limit, block size, block arrival rate, and the frame sizes) so as to capture their impact on the system-level performance. More importantly, our rigorous analysis of oVML system dynamics quantifies the end-to-end delay with BFL, which provides important insights into deriving optimal block arrival rate by considering communication and consensus delays. We present a variety of numerical and simulation results highlighting various non-trivial findings and insights for adaptive BFL design. In particular, based on analytical results, we minimize the system delay by exploiting the channel dynamics and demonstrate that the proposed idea of tuning the block arrival rate is provably online and capable of driving the system dynamics to the desired operating point. It also identifies the improved dependency on other blockchain parameters for a given set of channel conditions, retransmission limits, and frame sizes. 1 However, a number of challenges (gaps in knowledge) need to be resolved in order to realise these changes. In particular, we identify key bottleneck challenges requiring further investigations, and provide potential future reserach directions. 1 An early version of this work has been accepted for presentation in IEEE WCNC Wksps 2020 [1] .

269 citations

Journal ArticleDOI
TL;DR: An extensive and diverse classification of wearables, based on various factors, a discussion on wireless communication technologies, architectures, data processing aspects, and market status, as well as a variety of other actual information on wearable technology are provided.

197 citations