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MIMO PLC Capacity and Throughput Analysis
Published in Lars T. Berger, Andreas Schwager, Pascal Pagani, Daniel M. Schneider, MIMO Power Line Communications, 2017
Daniel M. Schneider, Pascal Pagani, Andreas Schwager
In the following, a wideband signal transmission is considered, where the transmitted signal s(f) is defined for a set of frequencies f in the range [fmin, fmax]. In general, multi-carrier transmission schemes, such as orthogonal frequency division multiplexing (OFDM), are used to convey wideband signals without suffering from inter-symbol interference (ISI) due to the frequency-selective nature of the channel. More information about MIMO-OFDM systems is detailed in Chapter 8. For transmission over a SISO channel, involving one Tx port and one Rx port, the relation between the received signal r(f) and the transmitted signal s(f)is given by () r(f)=h(f)s(f)+n(f),
High-Frequency Filters for Data Communication Applications
Published in Krzysztof Iniewski, Circuits at the Nanoscale, 2018
Manisha Gambhir, Vijay Dhanasekaran, Jose Silva-Martinez, Edgar Sánchez-Sinencio
With the advent of high-speed communication systems and wireless technology, there has been an increased demand for high-frequency circuits. High data rate communications systems require baseband circuitry suitable to cover wide signal bandwidths (BWs) up to few GHz. Currently, most of the integrated circuit solutions consist of analog-to-digital converters to digitize the incoming signals. Any digitizing architecture requires front-end filtering to limit the signal BW and prevent aliasing. Thus an analog filter is a universal part on any front-end chain. Wideband integrated filters are particularly needed for high data rate communication systems, digital versatile disk (DVD), and disk drive read channel systems and antialiasing filters for direct conversion architectures.
Spectrum Sensing
Published in Mohamed Ibnkahla, Cooperative Cognitive Radio Networks, 2018
MB-CRNs have recently caught the attention of several research organizations, since they can significantly enhance the SUs’ throughput. There are several scenarios where MB-CRN can be encountered such as Many modern communication systems and applications require a wideband access (e.g., ultra-wideband communications). The wideband spectrum can be divided into multiple subbands or subchannels. Thus, the problem becomes a multiband detection problem.When an SU wants to minimize the data interruptions due to the return of PUs to their bands, seamless handoff from one band to another becomes vital. Therefore, the SU must have backup channels besides those channels it has already accessed. With MB-CRNs, the SU does not only have a set of candidate channels, but it can also reduce handoff frequency.When an SU wants to achieve higher throughput or maintain a certain Quality of Service (QoS), then it may transmit over a larger bandwidth, and this is primarily enabled by accessing multiple bands.In cooperative communications, multiple SUs may share their detection results among each other. However, if each SU monitors a subset of subchannels, and then shares its results with others, then the entire spectrum can be sensed, and consequently, more opportunities are explored for spectrum access.
Ku-Band SIW Filter with High Fractional Bandwidth Optimized Using Feed Forward Back Propagation ANN
Published in IETE Journal of Research, 2023
Gopalakrishnan Soundarya, Nagarajan Gunavathi
Recent developments in wireless communication system require microwave components which are smaller in size, low cost, and lightweight. Nowadays, wide band filters play an important role due to its high data rate and assisting multiple signal transmission. The Substrate integrated waveguide (SIW) technology is extensively used because of its low loss, high-quality factor, and ease of integration [1]. Various microwave and millimeter wave components such as antennas [2], filters [3], and power dividers [4] are developed using SIW technology. In [5], SIW band pass filter using slotted resonators with wide bandwidth is reported, but it has poor in-band return loss. Various coupling topologies like negative coupling [6], electric cross-coupling [7], magnetic coupling [8], mixed electric and magnetic coupling [9] are utilized in the development of SIW band pass filter. These filters achieve high selectivity but at the cost of higher insertion loss.
Use of real time localization systems (RTLS) in the automotive production and the prospects of 5G – A literature review
Published in Production & Manufacturing Research, 2022
Christoph Küpper, Janina Rösch, Herwig Winkler
The development of Ultra-Wideband (UWB) technology began in the 1960s for radar applications. Later, it was extended using the orthogonal frequency division multiplexing (OFDM) method. This method converts wideband signals into narrowband orthogonal signals, which are modulated over many subcarriers at a relatively low data rate. The number of subcarriers is specified in thousands of k. For example, an OFDM-2k has 2,096 subcarriers. The IEEE.15.3 standard was used to standardize the data transmission technology. Here, however, it competed with Wi-Fi and was subsequently specified as an impulse radio technology in the IEEE 802.15.4a standard. Compared to other technologies, UWB transmits over a broad frequency spectrum between 3.1 GHz and 10.6 GHz (Ramos et al., 2016). It uses nano-pulses of about two nanoseconds which are easy to distinguish from reflections (Shi & Ming, 2016). This enables an accuracy of up to ±10 cm at LOS (Line of Sight) by calculating ToA, TDOA and AoA. (Al-Kadi & Zorn, 2020)
Compact UWB monopole antenna with quadruple band notched characteristics
Published in International Journal of Electronics, 2020
V N Koteswara Rao Devana, A. Maheswara Rao
The demand for wideband wireless communication is rapidly increasing due to provide more information with high data rate and due to the need to support more users. In 2002, the U.S. Federal Communications Commission allocated a frequency with a bandwidth of 3.1 ~ 10.6 GHz as unlicensed band for commercial use and has been getting increasingly popular from the academic and industry fields (Federal Communications Commission, 2002). As the Ultrawideband (UWB) antenna is the key component of the UWB wireless communication system, much attention is devoted to UWB antenna implementation. The feasible UWB antennas required to be design with compact size, low profile, low cost, simple structure, good impedance matching, stable radiation patterns, and constant gain over the entire operating band (Fan, Yin, Li, & Kang, 2011; Ray & Tiwari, 2010). To achieve these characteristics, planar monopole antennas are suitable, and hence the research activity is increasingly focused on them. The UWB technology provides short-range broadband communication, radar sensing, satellite, aircraft, body area networking and radio application. The bandwidth enhancement of UWB antennas has achieved by using defective ground structures along with the various shapes of resonating structures were reported in literature (Azim & Islam, 2011; Chiang & Tam, 2008; Jung, Choi, & Choi, 2005; Naser-Moghadasi, Danideh, Sadeghifakhr, & Reza-Azadi, 2009).