The telecommunications industry has seen a rapid boost within the last decade. New realities and visions of functionalities in various telecommunications networks have brought forward the concept of next-generation networks (NGNs). The competitions among operators for support- ing various services, lowering of the cost of having mobile and cellular phones and smartphones, increasing demand for general mobility, explosion of digital traffic, and advent of convergence network technologies added more dynamism in the idea of NGNs. In fact, facilitating con- vergence of networks and convergence of various types of services is a significant objective of NGN
標簽： Next-Generation Converged Building Networks
上傳時間： 2020-05-26
上傳用戶：shancjb
Advances in communication and networking technologies are rapidly making ubiq- uitous network connectivity a reality. Wireless networks are indispensable for supporting such access anywhere and at any time. Among various types of wire- less networks, multihop wireless networks (MWNs) have been attracting increasing attention for decades due to its broad civilian and military applications. Basically, a MWN is a network of nodes connected by wireless communication links. Due to the limited transmission range of the radio, many pairs of nodes in MWNs may not be able to communicate directly, hence they need other intermediate nodes to forward packets for them. Routing in such networks is an important issue and it poses great challenges.
標簽： Multihop Wireless Networks
上傳時間： 2020-05-31
上傳用戶：shancjb
The telecommunications industry has seen a rapid boost within the last decade. New realities and visions of functionalities in various telecommunications networks have brought forward the concept of next-generation networks (NGNs). The competitions among operators for support- ing various services, lowering of the cost of having mobile and cellular phones and smartphones, increasing demand for general mobility, explosion of digital traffic, and advent of convergence network technologies added more dynamism in the idea of NGNs. In fact, facilitating con- vergence of networks and convergence of various types of services is a significant objective of NGNs.
標簽： Next-Generation Converged Networks
上傳時間： 2020-05-31
上傳用戶：shancjb
his research aims at creating broadband tunable, fully integrated filters for the application of cognitive radio and signal classification receivers. The approach under study is the N-path filter technique which is capable of translating a baseband impedance to a reference frequency creating a tunable filter. The traditional N-path filter suffers from fundamental architectural limitations, namely : a trade-off between insertion loss and out-of-band rejection, reference clock feed- through, and jammer power handling limitations. In the first approach, the fundamental trade- off of the traditional N-path filter between insertion loss and out-of-band rejection is improved by a transmission line (T-line) N-path filter technique.
上傳時間： 2020-05-31
上傳用戶：shancjb
This paper presents a Hidden Markov Model (HMM)-based speech enhancement method, aiming at reducing non-stationary noise from speech signals. The system is based on the assumption that the speech and the noise are additive and uncorrelated. Cepstral features are used to extract statistical information from both the speech and the noise. A-priori statistical information is collected from long training sequences into ergodic hidden Markov models. Given the ergodic models for the speech and the noise, a compensated speech-noise model is created by means of parallel model combination, using a log-normal approximation. During the compensation, the mean of every mixture in the speech and noise model is stored. The stored means are then used in the enhancement process to create the most likely speech and noise power spectral distributions using the forward algorithm combined with mixture probability. The distributions are used to generate a Wiener filter for every observation. The paper includes a performance evaluation of the speech enhancer for stationary as well as non-stationary noise environment.
標簽： Telecommunications Processing Signal for
上傳時間： 2020-06-01
上傳用戶：shancjb
A wireless ad-hoc network is a wireless network deployed without any infrastructure. In such a network, there is no access point or wireless router to forward messages among the computing devices. Instead, these devices depend on the ad-hoc mode of their wireless net‐ work interface cards to communicate with each other. If the nodes are within the transmis‐ sion range of the wireless signal, they can send messages to each other directly. Otherwise, the nodes in between will forward the messages for them. Thus, each node is both an end system and a router simultaneously.
上傳時間： 2020-06-01
上傳用戶：shancjb
In the field of electricity, electrostatics, and circuit theory, there are many discoveries and accomplishments that have lead to the foundation of the field of electrostatic discharge (ESD) phenomenon. Below is a chronological list of key events that moved the field of electrostatics forward:
上傳時間： 2020-06-05
上傳用戶：shancjb
RFID is at a critical price point that could enable its large-scale adoption. What strengths are pushing it forward? What technical challenges and privacy concerns must we still address?
標簽： an-introduction-to-rfid-technolog
上傳時間： 2020-06-08
上傳用戶：shancjb
With the continued growth in the world's population, there is a need to ensure availability of enough food to feed everyone. Advances in science and technology have helped not only to increase food production, but also to reduce food wastage. However, the latter has the potential to be improved to a significant extent through appropriate matching of supply and demand, and with proper handling during storage and transit. Given the amount of food wastage that occurs after a food item leaves the “farm” on its way to the “fork,” and the availability of means to reduce such wastage, there really is no excuse for feigned ignorance.
標簽： Automation Industry Network Sensor RFID Food and the in
上傳時間： 2020-06-08
上傳用戶：shancjb
ABSTRACTThe flyback power stage is a popular choice for single and multiple output dc-to-dc converters at powerlevels of 150 Watts or less. Without the output inductor required in buck derived topologies, such as theforward or push-pull converter, the component count and cost are reduced. This application note will reviewthe design procedure for the power stage and control electronics of a flyback converter. In these isolatedconverters, the error signal from the secondary still needs to cross the isolation boundary to achieveregulation. By using the UC3965 Precision Reference with Low Offset Error Amplifier on the secondaryside to drive an optocoupler and the UCC3809 Economy Primary Side Controller on the primary side, asimple and low cost 50 Watt isolated power supply is realized.
標簽： 隔離
上傳時間： 2021-11-24
上傳用戶：kingwide
