Radar Sensor Wireless Channel Modeling in Foliage Environment: UWB Versus Narrowband

An improved triple-pulse high-power pulse-width modulation (HP-PWM) signal model is proposed to enhance the performance of current underwater sonar transmitter. The presented model is based on reducing the third and fifth harmonic energy of the HP-PWM signal. The achievement of low-power consumption has been implemented using class D amplifier and high-quality factor (High-Q) underwater acoustic transducer (UAT). High efficiency is demonstrated by simulations (reducing 41 % of the third and fifth harmonic energy). Feasibility of the presented model under different conditions has been proved by experiments.

Section: Introductionmentioning

confidence: 99%

High-efficiency and low-consumption underwater sonar transmitter with improved triple-pulse HP-PWM signal model based on class D amplifier

Duan

Jiang

et al. 2016

“…However, it is the relatively recent advances in hardware technology that are enabling a much wider range of design freedoms to be explored [3]. As a result, there are emerging and compelling changes in system requirements such as more efficient spectrum usage, higher sensitivities, greater information content, improved robustness to errors, and reduced interference emissions [4,5]. The combination of these changes is fueling a worldwide interest in the subject of waveform design and the use of waveform *Correspondence: ecemark@mail.tjnu.edu.cn College of Electronic and Communication Engineering, Tianjin Normal University, Tianjin, China diversity techniques [6].…”

Section: Introductionmentioning

confidence: 99%

A study of artificial bee colony variants for radar waveform design

Xiu

2016

Waveform design and diversity is the technology that allows one or more sensors (e.g., radar or radar sensor networks) on board a platform to automatically change operating parameters, e.g., frequency, gain pattern, and pulse repetition frequency, to meet the varying environments. Optimization problems in the design of radar waveforms such as polyphase code design often bring troubles to designers. This paper proposes to hybridize the migration operator of biogeography-based optimization (BBO) approach with artificial bee colony (ABC) algorithm. Migration operator is able to promote information exchange of solutions in bee colony. This is useful for exploiting good information of searched solutions. Moreover, three state-of-the-art ABC variants are taken for study. A spread spectrum polyphase code design problem is chosen for experiment. The proposed ABCBBO algorithm as well as three state-of-the-art ABC algorithms are applied to solve polyphase code design. Results show that ABCBBO presents the overall best performance amongst the test algorithms. It is also the most reliable one.

“…Since spectrum was a free cost to the designer there were few incentives to minimize spectrum footprint. However, with the growing interests on radar networks [2,3], spectrum allocation in radar network needs to be explored. However, the fixed spectrum management which allocates certain spectrum to the user leads to the low spectrum utilization rate.…”

Section: Introductionmentioning

confidence: 99%

“…A parallel spectrum allocation algorithm distributes many spectrums in single distribution cycle improving the spectrum efficiency. Literature [2] and [3] refer to the parallel algorithm as well. In order to get higher channel multiplexing rate, the literature [6] improved the parallel algorithm which make other users share the same channel with the user that have the largest label.…”

Section: Introductionmentioning

confidence: 99%

Research on an improved parallel algorithm based on user’s requirement in cognitive radar network

Yan

Wang

Bao

2015

In cognitive radar network, a parallel algorithm can allocate idle spectrum to cognitive radars, but it often ignores the user's requirement. According to the graph theory, the topology of the network is divided into two different groups. In the process of distributing spectrum, each group summarizes the distributed information after completing a distribution. When a user's demand is satisfied, every group is informed to not allocate the spectrum for the user anymore and deletes it from the topology at the same time. As a result, by deleting the node which the user's requirement has already been met, the other nodes which are interfered with the node on the same channel can participate into spectrum allocation. The improved algorithm can ensure high spectrum utilization taking a little time that is spent on the spectrum allocation. The simulation result shows that the spectrum utilization of the improved algorithm is higher than that of the traditional parallel algorithm, and the user's satisfaction increases greatly. Therefore, this paper aims to attempt to explore an improved parallel algorithm to resolve the problem by considering user's requirement.