856 research outputs found
Sub 1GHz M2M communications standardization: The advancement in white space utilization for enhancing the energy efficiency
Energy efficiency of machine to machine (M2M) communications terminals is one of the major design goals of M2M networks, resulting from anticipated over 50 billion M2M communications devices to be deployed into the networks by 2020 [1]. The stakeholders in the M2M communications have observed that it will be environmental and economic catastrophic to deploy M2M communications devices without solving the energy inefficiencies associated with wireless devices that are expected to be used for M2M communications. In view of the aforementioned energy challenge, sub 1GHz spectra have provided enormous opportunities that can be energy efficient, cost effective and coverage efficiency which can be utilized for M2M communications. This work will evaluate the energy efficiency benefits of optimized Sub 1GHz spectra for M2M communications
An Overview on IEEE 802.11bf: WLAN Sensing
With recent advancements, the wireless local area network (WLAN) or wireless
fidelity (Wi-Fi) technology has been successfully utilized to realize sensing
functionalities such as detection, localization, and recognition. However, the
WLANs standards are developed mainly for the purpose of communication, and thus
may not be able to meet the stringent requirements for emerging sensing
applications. To resolve this issue, a new Task Group (TG), namely IEEE
802.11bf, has been established by the IEEE 802.11 working group, with the
objective of creating a new amendment to the WLAN standard to meet advanced
sensing requirements while minimizing the effect on communications. This paper
provides a comprehensive overview on the up-to-date efforts in the IEEE
802.11bf TG. First, we introduce the definition of the 802.11bf amendment and
its formation and standardization timeline. Next, we discuss the WLAN sensing
use cases with the corresponding key performance indicator (KPI) requirements.
After reviewing previous WLAN sensing research based on communication-oriented
WLAN standards, we identify their limitations and underscore the practical need
for the new sensing-oriented amendment in 802.11bf. Furthermore, we discuss the
WLAN sensing framework and procedure used for measurement acquisition, by
considering both sensing at sub-7GHz and directional multi-gigabit (DMG)
sensing at 60 GHz, respectively, and address their shared features,
similarities, and differences. In addition, we present various candidate
technical features for IEEE 802.11bf, including waveform/sequence design,
feedback types, as well as quantization and compression techniques. We also
describe the methodologies and the channel modeling used by the IEEE 802.11bf
TG for evaluation. Finally, we discuss the challenges and future research
directions to motivate more research endeavors towards this field in details.Comment: 31 pages, 25 figures, this is a significant updated version of
arXiv:2207.0485
Survey of Inter-satellite Communication for Small Satellite Systems: Physical Layer to Network Layer View
Small satellite systems enable whole new class of missions for navigation,
communications, remote sensing and scientific research for both civilian and
military purposes. As individual spacecraft are limited by the size, mass and
power constraints, mass-produced small satellites in large constellations or
clusters could be useful in many science missions such as gravity mapping,
tracking of forest fires, finding water resources, etc. Constellation of
satellites provide improved spatial and temporal resolution of the target.
Small satellite constellations contribute innovative applications by replacing
a single asset with several very capable spacecraft which opens the door to new
applications. With increasing levels of autonomy, there will be a need for
remote communication networks to enable communication between spacecraft. These
space based networks will need to configure and maintain dynamic routes, manage
intermediate nodes, and reconfigure themselves to achieve mission objectives.
Hence, inter-satellite communication is a key aspect when satellites fly in
formation. In this paper, we present the various researches being conducted in
the small satellite community for implementing inter-satellite communications
based on the Open System Interconnection (OSI) model. This paper also reviews
the various design parameters applicable to the first three layers of the OSI
model, i.e., physical, data link and network layer. Based on the survey, we
also present a comprehensive list of design parameters useful for achieving
inter-satellite communications for multiple small satellite missions. Specific
topics include proposed solutions for some of the challenges faced by small
satellite systems, enabling operations using a network of small satellites, and
some examples of small satellite missions involving formation flying aspects.Comment: 51 pages, 21 Figures, 11 Tables, accepted in IEEE Communications
Surveys and Tutorial
Performance Investigation of Wireless LAN with Variable Channel Width
Today, mostly the wireless LAN is based on preset static channel widths. Considering unique benefits of adapting channel width, which is a fundamental yet under-explored facet in wireless communication, We carried out investigations on the performance of suggested scenario, which are based on IEEE 802.11 and composed of different number of nodes with different channel width (10MHz, 20 MHz and 40 MHz) associated to one AP. This research work makes a strong case for wireless systems that adapt channel width in WLAN. Adapting channel width offers rich possibilities for improving system performance. This thesis provides an outlook of the aforementioned issues associated with wireless communication for instance, fairness problem among users associated to same AP and hidden terminal problem. Some issues are investigated and analyzed with Matlab tool. We found that the variable channel width increases the range of communication, providing the users with the required spectrum, which offers a natural way to both improve flow fairness and balance the load across the APs. Also the increase in channel width increases the throughput of suggested scenario compare to the fixed channel width. In our future work, we also provide possible solutions to the new problems in WLAN with variable channel width
Survey of Spectrum Sharing for Inter-Technology Coexistence
Increasing capacity demands in emerging wireless technologies are expected to
be met by network densification and spectrum bands open to multiple
technologies. These will, in turn, increase the level of interference and also
result in more complex inter-technology interactions, which will need to be
managed through spectrum sharing mechanisms. Consequently, novel spectrum
sharing mechanisms should be designed to allow spectrum access for multiple
technologies, while efficiently utilizing the spectrum resources overall.
Importantly, it is not trivial to design such efficient mechanisms, not only
due to technical aspects, but also due to regulatory and business model
constraints. In this survey we address spectrum sharing mechanisms for wireless
inter-technology coexistence by means of a technology circle that incorporates
in a unified, system-level view the technical and non-technical aspects. We
thus systematically explore the spectrum sharing design space consisting of
parameters at different layers. Using this framework, we present a literature
review on inter-technology coexistence with a focus on wireless technologies
with equal spectrum access rights, i.e. (i) primary/primary, (ii)
secondary/secondary, and (iii) technologies operating in a spectrum commons.
Moreover, we reflect on our literature review to identify possible spectrum
sharing design solutions and performance evaluation approaches useful for
future coexistence cases. Finally, we discuss spectrum sharing design
challenges and suggest future research directions
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