The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The matrix converter (MC) is a promising topology for various applications due to its intrinsic advantages. In this sense, this type of converter represent an alternative for small wind turbines (SWT). Simulation is necessary to validate the controllers and study the interaction of the wind farm with the grid, but this is not feasible using traditional simulation techniques. This work proposes the...
Adaptive equalizer is a key deuce in modern data communication systems. It is capable of increase data transmission rates in modern digital radio communications systems. With the rapid development of the radio communications, adaptive equalization techniques become the study focus of many engineers. This thesis studies in adaptive equalization problems. And put the emphases in various adaptive equalizers,...
The technique of simulation can save the cost and speed the development. In this paper, the development and application of communication system simulation is introduced, as well as the special simulation tool - Anosft designer. The ansoft designer can be used to circuit design - planar EM design - system design independently or cooperatively. The modulation and demodulation of BPSK is simulated using...
A low power linearity-ratio-independent DAC for ΔΣ data converters is proposed in this paper. By using a gain-boosted sub-threshold inverter as an amplifier, circuit power consumption is decreased significantly. The sensitivity of the differential DAC output linearity on circuit mismatches is reduced by using mutually-referred inputs. In a 0.13um CMOS technology, Monte-Carlo analysis and transistor-level...
This manuscript presents a new method of synthesizing cascaded continuous-time Delta-Sigma Modulators. The coefficients for each stage are obtained by a discrete-time to continuous-time transformation. A detailed derivation of the digital cancellation logics for modulators based on discrete-time domain analysis is presented which leads to a simple implementation of circuits and is capable of correcting...
With progression of scaling technique in silicon complementary metal-oxide semiconductor (Si-CMOS) process, it is available to produce radio frequency (RF) circuits using Si-CMOS for broadband wireless system, to reduce cost and size of devices. But in contrast, Si-CMOS RF circuit is deteriorated from circuits which use compound semiconductors. In order to reduce RF circuit's requirements, we propose...
We present UTBB devices with a gate length (LG) of 25nm and competitive drive currents. The process flow features conventional gate-first high-k/metal and raised source/drains (RSD). Back bias (Vbb) enables Vt modulation of more than 125mV with a Vbb of 0.9V and BOX thickness of 12nm. This demonstrates the importance and viability of the UTBB structure for multi-Vt and power management applications...
High Peak to Average Power Ratio (PAPR) is one of the major drawbacks in Orthogonal Frequency Division Multiplexing (OFDM). The High PAPR increases the complexity of Analogue to Digital (A/D) and Digital to Analogue (D/A) convertors and also reduces the efficiency of RF High Power Amplifier (HPA). In this paper we present an analysis of Discrete Hartley Transform (DHT) precoded OFDM system using M-QAM...
This paper introduces the application of hybrid excitation synchronous machine (HESM) and two-stage matrix converter (TSMC) in variable-speed constant-frequency (VSCF) power system. A H-bridge is employed for excitation power circuit, which is combined with two-stage matrix converter (TSMC) as a module by sharing the dc-link of TSMC. This paper analyzed the modulation strategy of the system in two...
This paper presents a sigma-delta modulator of two-order with switched-capacitors (SC) techniques for low power in 0.18 um CMOS process. Without continues current transmission SC techniques present a discrete low power system. And a low power op amplifier with discrete common-mode feedback and a dynamic comparator is also designed. This new amp works under the supply of 1.8 v and with the direct current...
This paper presents a half-bridge-type inverter with hysteresis current control and unipolar modulation. The unipolar modulation strategy is adopted, thus the volume and weight of the output filter can be reduced compared with the conventional half-bridge inverter. In addition, as the voltage change during the switching process is just half of the input voltage, the switching losses can be reduced...
Carrier frequency estimation is important in both cooperative and non-cooperative communications. This paper addresses the estimation of the carrier frequency of a single-tone digitally modulated signal in the automatic modulation recognition (AMR) environment, where the AMR receiver does not have priori knowledge of the transmitted signal such as modulation type, shaping pulse, symbol constellation...
Orthogonal Frequency Division Multiplexing (OFDM) is predicted to be implemented in future broadcasting and Wireless Local Area Network (WLAN) systems due to its robustness in transmitting a high data rate. Some examples of current applications using OFDM include ETSI BRAN in Europe, IEEE802.11 in United States, and ARIB MMAC in Japan have adopted the OFDM transmission technology as a physical layer...
This paper investigates the error performance and precoder design for a bandwidth-efficient bit-interleaved coded modulation (BICM) system over a non-orthogonal amplify-and-forward (NAF)half-duplex single-relay channel. A tight union bound on the bit error probability (BEP) is first derived for an arbitrary block length of 2N using a 2N × 2N precoder. This bound provides an useful tool to predict...
In this paper we proposed two extensions to the recently proposed Phase Forward (PF) relaying strategy for cooperative communication. One extension is the replacement of CPFSK modulation by the more practical Gaussian filtered minimum shift keying (GMSK) modulation scheme. The second extension is the incorporation of antenna selection at the relay. Semi-analytical expressions for the bit error probabilities...
The paper analyzes power spectral density (PSD) of orthogonal pulse-based signals for time hopping ultra wideband (TH-UWB) systems. Our extensive studies show that the PSD of these signals not only depends on the time dithering code and the modulation schemes, but also on the energy spectral density (ESD) of orthogonal pulses. The different order orthogonal pulses provide different ESD which changes...
This paper studies expression of outage probability and partner selection strategies for cooperative network based on IDMA superposition modulation. By changing existing outage gain matrix into a symmetric new one and applying Hungary and WLF algorithm, a centralized optimal and a distributed sub-optimal partner selection strategies are proposed for superposition modulation cooperative multiple access...
The boom in user amount and voice traffic puts a huge pressure on the operators especially within populous countries, which forces them to enhance the voice capacity in the GSM evolution. The concept of Multi-User Reusing-One-Slot (MUROS) is promising to resolve this problem with negligible impact on handsets as well as to networks. In this paper, we compared the link-level and system-level performance...
In this paper, analysis of a novel class of A/D converters based on asynchronous delta modulation (DM) is presented and a high level model is realized for the same. Using the high level model, analytical expressions are derived for the calculation of the inband signal-to-quantization noise ratio (SQNR) for the case of sinusoidal inputs and two-tone inputs. For the special case of sinusoidal inputs,...
A novel switched-capacitor inverter is proposed. The proposed inverter outputs larger voltage than the input voltage by switched capacitors in series and in parallel. The maximum output voltage is decided by the number of the capacitors. The proposed inverter, which does not need any inductors, can be smaller than a conventional unit which consists of a boost converter and an inverter. Its output...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.