Serwis Infona wykorzystuje pliki cookies (ciasteczka). Są to wartości tekstowe, zapamiętywane przez przeglądarkę na urządzeniu użytkownika. Nasz serwis ma dostęp do tych wartości oraz wykorzystuje je do zapamiętania danych dotyczących użytkownika, takich jak np. ustawienia (typu widok ekranu, wybór języka interfejsu), zapamiętanie zalogowania. Korzystanie z serwisu Infona oznacza zgodę na zapis informacji i ich wykorzystanie dla celów korzytania z serwisu. Więcej informacji można znaleźć w Polityce prywatności oraz Regulaminie serwisu. Zamknięcie tego okienka potwierdza zapoznanie się z informacją o plikach cookies, akceptację polityki prywatności i regulaminu oraz sposobu wykorzystywania plików cookies w serwisie. Możesz zmienić ustawienia obsługi cookies w swojej przeglądarce.
A multi-mode WPAN transceiver implemented in an SoC is presented. Fabricated in 40-nm CMOS, the chip supports IEEE 802.15.4 and all modes of Bluetooth. Consuming 7.8 mW from a 1.2-V supply, the receiver has a sensitivity of −104, −98, −95/−94/−88 dBm in 802.15.4, BLE and Bluetooth BDR/EDR2/EDR3, respectively. The transmitter has a power consumption of 10 mW to deliver 0 dBm output in the constant...
Due to the obvious advantages in terms of aerial surveillance and anti-jamming, passive radar system (PRS) has been widely studied over the last years. However, a considerable part of the research on the PRS has been carried out in the laboratory environment and few practical results have been disclosed. In this paper, the design and implementation of an ongoing frequency modulated (FM)-based multi-frequency...
Symmetric α-stable (SαS) distribution noise is widely used to model co-channel and network interference in wireless communication systems. As robust and adaptive techniques, myriad filtering (MyF) and spherically symmetric vector MyF have been applied to suppress univariate and spherically symmetric multivariate SαS distribution noise, respectively. At a communication receiver, the received band-pass...
For digital terrestrial television broadcasting (DT-TB) systems, orthogonal frequency division multiplexing (OFDM) technique is considered to be an effective method to combat the frequency selective channel cause by multi-path effect. In the single frequency network (SFN) scenario, Alamouti space frequency block coding (SFBC) is introduced to provide spatial diversity gain and improve the link stability...
This paper presents a novel practical transmission signal design that enables a mobile satellite network to alert user terminals operating in a heavily power attenuated environment, such as inside buildings or in shadowed areas. In particular, we describe in detail a waveform design employing an orthogonal sequence modulated with p/2-BPSK and encoded with Reed-Solomon codes. The transmit waveform...
The P-code generator is a critical component in P-code acquisition. The model of the generator is used to determine the register's initial states. Consider the model is mainly consisted of six dividers, all of which have fixed width of dividend and divisor; two novel designs of divider based on the digit-recurrence division algorithm are presented that can improve the area-consuming and latency compared...
Direct-sequence spread spectrum (DSSS) is a candidate technique for long range acoustic communications (LRAC) in deep water. However, its data rate is quite low. To achieve a higher data rate, M-ary parallel combinatory communication (MPCC) scheme is adopted in this paper. The major obstacle encountered for LRAC is extended multipath propagation, which would cause severe inter-symbol interference...
The recent proliferation of multi-constellation Global Navigation Satellite Systems (GNSS) is offering a great opportunity for ionosphere scintillation studies. Since 2009, our research team has established permanent and temporary portable ionosphere scintillation monitoring and data collection systems in Alaska, Ascension Island, Hong Kong, Peru, and Singapore to collect multi-constellation multi-frequency...
Physical layer security is envisaged to provide secure wireless communications. So far there exist schemes that both achieve physical layer security and maintain a reasonable level of link capacity. However, in all these schemes, capacity of a communication link depends on the channel characteristics of both the communication link and the eavesdropping links. Thus, when packets are scheduled in a...
In this paper, we investigate the effective capacity of a secondary user in Nakagami-m fading channels, where the secondary user has no channel side information and transmits with a pre-defined rate r. By analyzing the optimal transmission rate r∗, the maximum effective capacity is obtained. The results show that effective capacity becomes smaller if the delay QoS constraint is tightened up. Moreover,...
The objective of this paper is to present and compare performances of several time-frequency analysis algorithms that characterize and associate ionosphere scintillation events focusing on carrier phase measurements obtained from three relatively close spaced antennas in Alaska. The results will be used to derive plasma drift velocity and estimate the 2-dimension size of the scintillation patches...
In this paper, we present a reliable and efficient algorithm to traversal all nodes in large-scale structured peer-to-peer environment. Our solution divides the whole node namespace into seamless subareas based the inherent regulation of structured P2P system. For the reliability, we combine the message validation mechanism into broadcasting scheme. The resulting scheme provides higher reliability...
Vacuum solar receiver is the key component in parabolic trough solar system. Due to different expansion increment between metal absorber and glass, corrugated expansion joint (metal bellows) is necessary to compensate the extra expansion increment. The mechanical and thermal properties of metal bellows have significant influence on the reliability and heat loss of solar receiver. Recently, China's...
To reduce the complexity of existing transmit diversity solutions for time domain synchronous OFDM (TDS-OFDM), a simple transmit diversity scheme is proposed in this paper. The space shifted constant amplitude zero autocorrelation (CAZAC) sequence is used for time-domain channel estimation. Two types of flexible frame structures are investigated for cyclicity reconstruction of the received inverse...
Time domain synchronous OFDM (TDS-OFDM) with higher spectral efficiency than cyclic prefix OFDM (CP-OFDM)was originally proposed for downlink broadcasting transmission. To support multi-user uplink scenarios, this paper proposes a novel multiple access scheme called time domain synchronous frequency division multiple access (TDS-FDMA), wherein an uniform frame structure and its corresponding receiver...
The existing transmit diversity schemes for time domain synchronous OFDM (TDS-OFDM) is only suitable either for fast time-varying but weakly frequency-selective channels, or strongly frequency-selective but slow fading channels. In this paper, the space-time shifted constant amplitude zero autocorrelation (CAZAC) sequence based TDS-OFDM transmit diversity scheme is proposed for doubly selective channels...
To improve the system capacity of conventional orthogonal frequency division multiplexing (OFDM) systems, the layered modulation OFDM scheme is proposed. The modulated OFDM symbols are separated into two layers as differential modulated symbols and coherent symbols. The differential symbols are used as pilots, which are combined with the coherent modulated data and sent out by the transmitter. At...
This article designed a GPS IF signal simulator 1which is based on the software; it can simulate the GPS IF signal after the user assigned the moving condition of its carrier. It is very facility for the GPS software receiver to research or validate its arithmetic. The papers start with GPS IF signal architecture; illustrate the theory and arithmetic of simulator, then give the detail flow chart for...
Wireless mesh networks (WMNs) have recently emerged as a promising broadband access infrastructure for next-generation wireless networking. Several approaches that exploit directional antennas have been proposed in the literature to increase the performance of WMNs. In this paper, we study the interference optimization multicast problem in WMNs where nodes are equipped with directional antennas. Interference...
For the purpose of improving to redundancy of the transmission path, compensating for poor communication quality of wireless communication in harsh industrial environments and partly improving reliability of industrial wireless networked control system (WNCS), the multi-path transmission mechanism based on topology of dual-band and secondary structure is proposed. The topology of dual-band and secondary...
Podaj zakres dat dla filtrowania wyświetlonych wyników. Możesz podać datę początkową, końcową lub obie daty. Daty możesz wpisać ręcznie lub wybrać za pomocą kalendarza.