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The success of modern electronics is built on the possibility to accurately predict system behavior by using simulation tools. This paradigm can be extended to components such as piezoelectric transducers attached to the electronics. The ability to simulate both piezoelectric transducer and electronics together renders possible effective optimizations at system level, i.e. minimizing size, cost and power consumption. In this paper a computer simulation of a combined electronics and piezoelectric transducer system is explored. The analogy between acoustic wave propagation and wave propagation in an electric transmission line is given. The simulation approach is applied to a pulser-receiver setup for the determination of speed of sound and attenuation in liquids. Experiments and simulations are made for fixed temperature and in the frequency range 1–10 MHz using ethanol, methanol, carbon tetrachloride, acetone, benzene and distilled water as test samples. Comparison shows a good agreement between simulation and experiments. Furthermore, the use of an ultrasonic simulation package allows for the development of the associated electronics to amplify and process the received ultrasonic signals.

An L1 band highly integrated low noise GPS receiver in 0.18-μm CMOS is presented in this paper. The receiver adopts double conversion structure and two dynamic range control modes of variable gain amplifier (VGA) and programmable gain amplifier (PGA). The receiver includes the blocks of LNA, down-conversion mixers, band pass filter, received signal strength indicator (RSSI), VGA, PGA, 2-bit ADC, two frequency synthesizers and so on. The LNA adopts source inductive degeneration technique to achieve good noise performance, and a novel positive feedback capacitor is introduced to enhance gain. The novel gain-boosting charge pump (CP) structure acquires accurate current matching of 0.1% error which improves the output phase noise of frequency synthesizer. The measured radio performances of noise figure (NF) is only 4 dB and the maximum gain is 110 dB. The gain control range achieves 50 dB provided by PGA and VGA. The receiver occupies an area of 1.875 mm × 1.575 mm including all needed voltage reference and the 1.8 V low dropout regulator.

In traditional phased-array T/R modules, front-end modules such as limiter, low-noise amplifier (LNA) and RF switch are generally implemented by independent devices, with low integration and high cost. This paper realizes the integration of all receiver functional modules in the 0.13$\mu$m CMOS SOI process, including RF switch, LNA with limiter, 6-bit digital controlled attenuator and phase shifter, and drive amplifier. The LNA integrates a limiting function, which can suffer 2W continuous wave. Fast charge–discharge circuit is applied to the low insertion loss RF switch, which greatly reduces the switching time. The phase shifter adopts a double balanced switch used for 180^∘ phase shift, which significantly reduces the phase error. The measured channel gain is about 28dB with an NF about 2.3dB and an IP1 dB above $-$14dBm. The state error of attenuator is less than $+∕-0.6$dB with step error less than $+∕-0.3$dB. The RMS phase error of phase shifter is less than 1.8 degrees. The fully integrated transceiver IC occupies an area of $5\times 5.6$mm². This receiver draws only 128mA with a 3.3V power supply.

Chaotic communication requires the knowledge of corresponding phase relationship between the primary phase of Duffing oscillator’s internal driving force and the primary phase of the undetected signal. Currently, there is no method of noncoherent demodulation for DPSK (Differential Phase Shift Keying) signal and mobile communication signal by Duffing oscillator. To solve this problem, this study presents a noncoherent demodulation method based on the Duffing oscillators array and Duffing oscillator optimization. We first present the model of Duffing oscillator and its sensitivity to undetected signal primary phase. Then the zone partition is proposed to identify the Duffing oscillator’s phase trajectory, and subsequently, the mathematical model and implementation method of the Duffing oscillators array are outlined. Thirdly, the Duffing oscillator optimization and its adaptive strobe technique are proposed, also their application to DPSK signal noncoherent demodulation are discussed. Finally, the design of new concept DPSK chaotic digital receiver based on the Duffing oscillators array is presented, together with its simulation results obtained by using SystemView simulation platform. The simulation results suggest that the new concept receiver based on the Duffing oscillator optimization of Duffing oscillators array owns better SNR (signal-to-noise ratio) threshold property than typical existing receivers (chaotic or nonchaotic) in the AWGN (additive white Gaussian noise) channel and multipath Rayleigh fading channel. In addition, the new concept receiver may detect mobile communication signal.

We have developed, manufactured, and tested a new feed design for interferometric radio telescopes with “large-N, small-D” designs. Such arrays require low-cost and low-complexity feeds for mass production on reasonable timescales and budgets, and also require those feeds to be compact to minimize obstruction of the dishes, along with having ultra-wide frequency bands of operation for most current and future science goals. The feed presented in this paper modifies the exponentially tapered slot antenna (Vivaldi) and quad-ridged flared horn antenna designs by having an oversized backshort, a novel method of maintaining a small size that is well-suited for deeper dishes ($f∕D\le 0.25$). It is made of laser cut aluminum and printed circuit boards, such that it is inexpensive ($\lesssim 75$USD per feed in large-scale production) and quick to build; it has a 5:1 frequency ratio, and its size is approximately a third of its longest operating wavelength. We present the science and engineering constraints that went into design decisions, the development and optimization process, and the simulated performance. A version of this feed design was optimized and fabricated for the Canadian Hydrogen Observatory and Radio-transient Detector (CHORD) prototypes. When simulated on CHORD’s very deep dishes ($f∕D=0.21$) and with CHORD’s custom first-stage amplifiers, the on-sky system temperature $T_{\mathrm{\text{sys}}}$ of the complete receiving system from dish to digitizer remains below 30K over most of the 0.3–1.5GHz band, and maintains an aperture efficiency ${\eta }_{\mathrm{\text{A}}}$ between 0.4 and 0.6. The entire receiving chain operates at ambient temperature. The feed is designed to slightly under-illuminate the CHORD dishes, in order to minimize coupling between array elements and spillover.

The uncertainty range of Doppler shift when GNSS receivers restart causes slow acquisition, in this paper we present an acquisition scheme with INS assistance to narrow down the Doppler search range. Doppler shift caused by user’s movement along LOS (Line of Sight) can be calculated based on the velocity provided by INS. Details of normal acquisition under different receiver dynamic in hot start are expounded firstly. Then inertial sensors error models are described and different grade INS velocity outputs are given. Simulations and comparisons are made to show the performance improvement of acquisition time in hot start with and without INS assistance. It is concluded that the acquisition time decreases with the INS assistance and performance improves more with higher grade INS. In conclusion, it is unnecessary to use INS to assist acquisition for low dynamic receiver during the hot start interval. For middle dynamic receivers, the consumer grade INS can offer effective velocity value for about 195 seconds, the automotive grade can provide available velocity for about 7 minutes, the time for tactical grade is about 77 minutes, and the navigation grade INS is serviceable during the whole hot start period. For the high dynamic users, the consumer INS can be useful for 10 minutes, the automotive INS can be effective for 17 minutes, and the tactical and navigation INS are always effective. The acquisition time can reduce 98.95% when velocity error is 5 m/s under high dynamic, 89.14% even when the velocity error is up to 500m/s.

In the IEEE Standard 802.15.4 for ZigBee, it sets the parameters of the ZigBee modules needed to be tested. One of the most important parameters is the test of the module receiver sensitivity. Although the requirements and the testing method of this specification has been given in the standard, there is still a huge difference from specification in practical. According to the result in the lab, the difference between these two values is almost 20dB. This article firstly introduces the results of sensitivity testing by using different vector signal generators, ZigBee module, spatial transmission in the laboratory environment and then analysis the experiment results. According to the analysis results, the sensitivity is then tested by spatial transmission in anechoic chamber and shielded enclosure. Based on the test mentioned above, it is proved the reason of sensitivity reducing determined previously. The research result of this article could have an improvement to the practical use of ZigBee.

Scientific discoveries, especially over the last six decades, have left no doubt that ‘information’ plays a central role in biology. Specialists have thus sought to study the information in biological systems using the same definitions of information as have been traditionally used in engineering, computer science, mathematics and in other disciplines. Unfortunately, all of these traditional definitions lack aspects that even non-specialists recognize as being essential attributes of information — qualities such as meaning and purpose. To remedy that deficiency, we define another type of information — Universal Information — that more accurately embodies the full measure of information. We then examine the DNA/RNA protein synthesizing system with this definition of Universal Information and conclude that Universal Information is indeed present and that it is essential for all biological life. Furthermore, other types of information, such as Mental Imaging Information, also play a key role in life. It thus seems inevitable that the biological sciences (and science in general) must consider other-than-the-traditional definitions of information if we are to answer some of the fundamental questions about life.

The QiTai radio Telescope (QTT) is a fully steerable Gregorian-type telescope with the main reflector aperture 110 m in diameter. QTT adopts an umbrella support, homology-symmetric lightweight design, and the main reflector is active adjustable through actuators. QTT will operate from 150 MHz to 115 GHz frequency and ultra-wideband receivers and large field-of-view multi-beam receivers will be equipped. A multi-function signal processing system based on RFSoC and GPU processor will be developed. QTT will allow high sensitivity observations on pulsars, spectral line, continuum and Very Long Baseline Interferometer (VLBI) observing modes, and form a world-class observational platform in these areas. This chapter briefly introduces the engineering design and the science goals of QTT.