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Electronic Communications
Published in Dale R. Patrick, Stephen W. Fardo, Electricity and Electronics Fundamentals, 2020
Dale R. Patrick, Stephen W. Fardo
The space that an AM signal occupies with its frequency is called a channel. The bandwidth of an AM channel is twice the highest modulating frequency. For our 1kHz modulating component, a 2-kHz bandwidth is needed, which would be 1 kHz above and below the carrier frequency of 1 MHz. In commercial AM broadcasting, a station is assigned a 10-kHz channel which limits the AM modulation component to a frequency of 5 kHz. Figure 7-19 shows the side-bands produced by a standard AM station.
Force-System Resultants and Equilibrium
Published in Richard C. Dorf, The Engineering Handbook, 2018
In amplitude modulation (AM), the message signal m(t) is embedded in the amplitude of the carrier c(t)=Accos2πfct+ϕc where Ac is the amplitude, ϕc is the phase and fc is the frequency of the carrier signal. There are several amplitude modulation techniques, namely, double sideband suppressed carrier (DSB-SC) AM, conventional AM, single sideband (SSB) AM, and vestigial sideband (VSB) AM.
Frequency Modulation
Published in Jerry C. Whitaker, The RF Transmission Systems Handbook, 2017
Frequency modulation differs from amplitude modulation in that the modulated wave consists of the carrier frequency and numerous sideband components that are generated for each modulating frequency. Recall that AM consists of a carrier and an upper and lower sideband. The bandwidth of an AM signal is determined by the highest frequency of the modulating signal. For example, a carrier is modulated by an audio signal which contains frequencies up to 4000 Hz. The AM bandwidth would therefore be: (2)(4000) = 8000 Hz.
Integration of sparse singular vector decomposition and statistical process control for traffic monitoring and quality of service improvement in mission-critical communication networks
Published in IISE Transactions, 2018
DPI examines packet contents, which has major concerns in terms of privacy breaches. AM and PM do not have this issue. AM works by injecting probing packets into the network and tracking these packets to detect QoS problems. A major drawback of AM is that it may disturb normal network operations. PM analyzes real packet data. The mainstay PM tools are relatively simple statistical methods, which do not suffice for MCCNs due to two reasons:Network-wide monitoring, change detection, and fault diagnosis are needed, as MCCNs are typically deployed to perform coordinated team work, whereas existing PM methods focus on individual nodes, links, or sub-networks.Highly efficient algorithms are needed for real-time analytics of packet data in MCCNs that are temporally high-throughput and spatially densely-connected networks.