SAE J1939-71-2008 Vehicle Application Layer

扩频通信，即扩展频谱通信(Spread Spectrum Communication)，它与光纤通信、卫星通信，一同被誉为进入信息时代的三大高技术通信传输方式。

The future satellite communication systems are re- quired to support the higher transmission data rate for providing the multimedia services by employing the e铿僣ient modulation method such as multi-level QAM.

NVP6134B AHD RX 芯片支持300MP摄像机(The NVP6134B AHD RX chip supports 300MP cameras)

华为内部员工学习资料，对于想进华为的朋友会有很大帮助。(The internal staff s learning materials in huawei is more helpfull for someone who want to go huawei.)

this file talk about network

本书描述了4G LTE / 5G NR 无线接入技术。(This book describes LTE, developed in 3GPP and providing true fourth-generation (4G) broadband mobile access, as well as the new radio-access technology 3GPP is currently working on. Together, these two technologies will provide 5G wireless access.)

Multiple input multiple output techniques combined with orthogonal frequency division multiplexing (MIMO-OFDM) provide a promising approach for wireless systems. However, a serious drawback of the OFDM system is the high peak-toaverage power ratio (PAPR), which may severely affect the power efficiency of RF power amplifiers. In this paper, we propose a simple method to reduce the PAPR of MIMO-OFDM signals based on the use of unused subcarriers. Instead of processing the signals at each transmitter separately, a peak cancelling signal is generated at one antenna and is then applied to all the others with only simple modifications. Simulation has shown that a minimum 2 dB reduction in PAPR can be achieved for all transmit signals using this approach. As the signal processing is nearly all done at a single transmitter, repetition of the operations at each transmitter is avoided, and therefore the overall cost of the system can be significantly reduced.

扩频通信完整的课件和习题答案，清华经典教材，学习无线移动以及跳频通信的基础(Spread spectrum communication courseware and exercises complete answer, Tsinghua classic textbook, learning, and frequency hopping wireless mobile communication base)

匹配滤波器的实现。主要是通过fft变化使输出自相关最大，在通过滤波器。(Matched filter implementation. Mainly through changes in the output autocorrelation fft the largest through the filter.)

Matlab与STK连接函数库，可以实现Matlab与STK连接(Matlab connection with the STK library)