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The coexistence of radar-sensing and communication systems research has received a surge of interest in recent times to tackle the issue of spectrum inadequacy. Designing an optimized radar waveform for a coexistence scenario has been a challenging task for accomplishing the convergence of radar-sensing and communication functionalities, without degrading the performance at either end. This paper proposes a novel global optimization-based Spatial Branch and Bound (SBnB) approach to optimize the phase coefficients of a Non-Linear Frequency Modulated (NLFM) waveform in a CRCS framework. In addition, the Modified-Power Ratio Constraint-Cramér–Rao Lower Bound (M-PRC-CRLB), a local optimization-based approach is proposed to optimize the phase coefficients of an NLFM waveform. The spectral energy distribution and auto-correlation characteristics of an NLFM waveform are comprehensively investigated for various values of polynomial order (N) and at different threshold Signal-to-Noise-Ratio (SNR) values. To compare the proposed waveform design approaches (M-PRC-CRLB, SBnB) with the existing waveform design approaches namely, Minimum Estimation Error Variance (MEEV) and PRC- CRLB, a Peak-to-Side-Lobe-Ratio (PSLR), and Integrated-Side-Lobe-Ratio (ISLR) are evaluated at various polynomial orders and threshold SNR values. Furthermore, the performance of a CRCS is assessed using the radar estimation rate and communication data rate. The simulation results reveal that the proposed optimized radar waveform design approaches provide improved performance compared to the existing radar waveform design approaches in terms of radar estimation rate. Further, the proposed global optimization-based SBnB approach achieves a comparable performance of the communication data rate. In addition, the proposed approaches accomplish enhanced spectral utilization, controlled side-lobe energy levels, reduced range-domain ambiguities, and a higher information rate in a CRCS. 相似文献
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在调幅-调频收音机安装完成后,会遇到各种问题,严重的影响到收听的效果和质量。因此需要对其进行精确地调试及检测,进而保证收音机的接收效果。文中分析了S205-2T型收音机在AM波段和FM波段的调试方法,并详细介绍了相应的调试步骤及技巧。经实践验证,这些新型调试方法可以快速准确的调试收音机,极大改善接收效果,并且为同类收音机的调试检测工作提供借鉴。 相似文献
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随着数字化技术的深入发展及音频广播业的不断扩大,音频广播数字化的发展获得了强劲的推动力.目前国际上主流的数字声音广播技术有数字音频广播(DAB)、数字调幅广播(DRM)、数字高清广播(HD-Radio)等,这些技术各有其优势特点,但也各有适用性.探讨了中国数字化声音广播的发展方向,介绍了一种全新的带内高清数字广播技术系... 相似文献
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为了提高语音信号的质量,降低在语音拾取过程中背景噪声的干扰,设计了以FM1182为核心芯片的系统,该系统使用了双麦克风拾音技术。拾取到的两路信号,分别为混有背景噪声的语音信号和纯噪声信号,经过低噪的前置放大后,进入DSP芯片进行消噪运算,芯片采用AMBIN算法。通过实际电路的测试结果表明,湮没在噪声信号中的语音信号被成功提取。该系统具有集成度高,便携,成本低的特点,在保证有较高噪声处理效率的同时维持超低功耗,消噪效果十分明显,并具有较宽的噪声处理范围。 相似文献
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The bulk of the analytical data of a long period was used for estimation of RSD values of the CHNS analysis results obtained by EuroVector EA-3000 in the single-reactor mode. It is shown that the accident error level is conducted with the sample preparation procedure as well as with the properties of the certain analyzed samples. It is established that the experimental obtained CHNS analysis error levels significantly differ from those given in the technical specifications. In case of analysis of sample with the unknown composition the accidental errors of determination of each element are comparable with the standard sample ones. 相似文献
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通过时TS3000 总硫分析仪气体进样模块的简单改装,利用仪器的富集功能,使其可以分析由质量流量控制器原理发生的低含量、低压力的硫化氢气体,解决了TS3000 总硫分析仪不能检测压力较低样品的难题.对不同含量硫化氢样气体的分析结果表明,改装后的仪器仍具有很好的线性及准确度,同时验证了仪器改装方法的可行性. 相似文献
60.
Zaid A. Shamsan Tharek A. Rahman Muhammad R. Kamarudin Abdulaziz M. Al‐hetar Han‐Shin Jo 《ETRI Journal》2011,33(2):279-282
Coexistence analysis is extremely important in examining the possibility for spectrum sharing between orthogonal frequency‐division multiplexing (OFDM)‐based international mobile telecommunications (IMT)‐Advanced and other wireless services. In this letter, a new closed form method is derived based on power spectral density analysis in order to analyze the coexistence of OFDM‐based IMT‐Advanced systems and broadcasting frequency modulation (FM) systems. The proposed method evaluates more exact interference power of IMT‐Advanced systems in FM broadcasting systems than the advanced minimum coupling loss (A‐MCL) method. Numerical results show that the interference power is 1.3 dB and 3 dB less than that obtained using the A‐MCL method at cochannel and adjacent channel, respectively. This reduces the minimum separation distance between the two systems, which eventually saves spectrum resources. 相似文献