At the macroscopic level of system layout, the most important issue is path loss. In the older mobile radio systems that are limited by receiver noise, path loss determines SNR and the maximum coverage area. In cellular systems, where the limiting factor is cochannel interference, path loss determines the degree to which transmitters in different cells interfere with each other, and therefore the minimum separation before channels can be reused.
標(biāo)簽： Characteristics Channel Mobile
上傳時(shí)間： 2020-05-30
上傳用戶：shancjb
Intensive development of digital technologies coincided in time with the beginning of the new era in telecommunications. It made possible to formalize many proce- dures of data exchange and to atomize some operations which made providing of serviceandmakeworkofmanytelecommunicationworkersmucheasier. Somenew telecommunication technologies were born out of the necessity for use of specific configurations of network elements and networks, as well as for a possibility of providing maximum characteristics of efficiency combined with high requirements to the stability of operation, the overcoming of different catastrophic situations and deadlockconditions,such as failuresand ”pending”of the networkandthe like. The thresholdbetweeninformationsystems andtelecommunicationsystems has become practically invisible. It resulted in such a new term as ”infocommunication”
標(biāo)簽： Telecommunication+Systems
上傳時(shí)間： 2020-06-01
上傳用戶：shancjb
基于TMS320F2812 光伏并網(wǎng)發(fā)電模擬裝置PROTEL設(shè)計(jì)原理圖+PCB+軟件源碼+WORD論文文檔,硬件采用2層板設(shè)計(jì)，PROTEL99SE 設(shè)計(jì)的工程文件，包括完整的原理圖和PCB文件，可以做為你的學(xué)習(xí)設(shè)計(jì)參考。 摘要：本文實(shí)現(xiàn)了一個(gè)基于TMS320F2812 DSP芯片的光伏并網(wǎng)發(fā)電模擬裝置，采用直流穩(wěn)壓源和滑動(dòng)變阻器來模擬光伏電池。通過TMS320F2812 DSP芯片ADC模塊實(shí)時(shí)采樣模擬電網(wǎng)電壓的正弦參考信號、光伏電池輸出電壓、負(fù)載電壓電流反饋信號等。經(jīng)過數(shù)據(jù)處理后，用PWM模塊產(chǎn)生實(shí)時(shí)的SPWM 波，控制MOSFET逆變?nèi)珮蜉敵稣也ā１疚挠肞I控制算法實(shí)現(xiàn)了輸出信號對給定模擬電網(wǎng)電壓的正弦參考信號的頻率和相位跟蹤，用恒定電壓法實(shí)現(xiàn)了光伏電池最大功率點(diǎn)跟蹤（MPPT），從而達(dá)到模擬并網(wǎng)的效果。另外本裝置還實(shí)現(xiàn)了光伏電池輸出欠壓、負(fù)載過流保護(hù)功能以及光伏電池輸出欠壓、過流保護(hù)自恢復(fù)功能、聲光報(bào)警功能、孤島效應(yīng)的檢測、保護(hù)與自恢復(fù)功能。系統(tǒng)測試結(jié)果表明本設(shè)計(jì)完全滿定設(shè)計(jì)要求。關(guān)鍵詞：光伏并網(wǎng)，MPPT，DSP Photovoltaic Grid-connected generation simulator Zhangyuxin，Tantiancheng，Xiewuyang(College of Electrical Engineering, Chongqing University)Abstract: This paper presents a photovoltaic grid-connected generation simulator which is based on TMS320F2812 DSP, with a DC voltage source and a variable resistor to simulate the characteristic of photovoltaic cells. We use the internal AD converter to real-time sampling the referenced grid voltage signal, outputting voltage of photovoltaic, feedback outputting voltage and current signal. The PWM module generates SVPWM according to the calculation of the real-time sampling data, to control the full MOSFET inverter bridge output sine wave. We realized that the output voltage of the simulator can track the frequency and phase of the referenced grid voltage with PI regulation, and the maximum photovoltaic power tracking with constant voltage regulation, thereby achieved the purpose of grid-connected simulation. Additionally, this device has the over-voltage and over-current protection, audible and visual alarm, islanding detecting and protection, and it can recover automatically. The testing shows that our design is feasible.Keywords: Photovoltaic Grid-connected，MPPT，DSP 目錄引言 11. 方案論證 11.1. 總體介紹 11.2. 光伏電池模擬裝置 11.3. DC-AC逆變橋 11.4. MOSFET驅(qū)動(dòng)電路方案 21.5. 逆變電路的變頻控制方案 22. 理論分析與計(jì)算 22.1. SPWM產(chǎn)生 22.1.1. 規(guī)則采樣法 22.1.2. SPWM 脈沖的計(jì)算公式 32.1.3. SPWM 脈沖計(jì)算公式中的參數(shù)計(jì)算 32.1.4. TMS320F2812 DSP控制器的事件管理單元 42.1.5. 軟件設(shè)計(jì)方法 62.2. MPPT的控制方法與參數(shù)計(jì)算 72.3. 同頻、同相的控制方法和參數(shù)計(jì)算 8
標(biāo)簽： tms320f2812 光伏 并網(wǎng)發(fā)電 模擬 protel pcb
上傳時(shí)間： 2021-11-02
上傳用戶：
ICN6201/02 is a bridge chip which receives MIPI? DSI inputs and sends LVDS outputs. MIPI? DSI supports up to 4 lanes and each lane operates at 1Gbps maximum; the totally maximum input bandwidth is 4Gbps; and the MIPI defined ULPS(ultra-low-power state) is also supported. ICN6201 decodes MIPI? DSI 18bepp RGB666 and 24bpp RGB888 packets.The LVDS output 18 or 24 bits pixel with 25MHz to 154MHz, by VESA or JEIDA format.ICN6201/02 support video resolution up to FHD (1920x1080) and WUXGA (1920x1200).ICN6201 adopts QFN48 package and ICN6202 adopts QFN40 package
標(biāo)簽： icn6202
上傳時(shí)間： 2022-06-10
上傳用戶：kingwide
The information disclosed to you hereunder (the Materials ) is provided solely for the selection and use of Xilinx products. To the maximum extent permitted by applicable law: (1) Materials are made available"AS IS"and with all faults, Xilinx hereby DISCLAIMS ALL WARRANTIES AND CONDITIONS, EXPRESS, IMPLIED, OR ST ATUTORY, INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY NON-INFRINGEMENT, OR FITNESS FOR ANY PARTICULAR PURPOSE; and (2) Xilinx shall not be liable (whether in contract or tort. includina nealigence. or under anv other theorv of liabilitv) for any loss or damage of any kind or nature related to, arising under, or in connection with, the Materials (including vour use of the Materials), including for any direct, indirect, special, incidental, or consequential loss or damage (including loss of data, profits, qoodwill, or any type of loss or damage suffered as a result of anv action brought by a third party)
上傳時(shí)間： 2022-06-18
上傳用戶：
在光伏發(fā)電系統(tǒng)中，光伏電池的利用率除了與光伏電池的內(nèi)部特性有關(guān)外，還受使用環(huán)境如輻照度、負(fù)載和溫度等因素的影響。在不同的外界條件下，光伏電池可運(yùn)行在不同且惟一的最大功率點(diǎn)（Maximum Power Point，MPP）上，因此，對于光伏發(fā)電系統(tǒng)來說，應(yīng)該尋求光伏電池的最優(yōu)工作狀態(tài)，以最大限度地將光能轉(zhuǎn)化為電能，即需要采用最大功率點(diǎn)跟蹤（Maximum Power Point Tracking，MPPT）技術(shù).本文根據(jù)光伏電池最大輸出功率與光照度的關(guān)系，建立了基于Boost電路的MPPT仿真模型，采用擾動(dòng)觀測法，通過調(diào)整DC-DC電路的占空比實(shí)現(xiàn)了最大功率點(diǎn)追蹤。使用Matlab/Simulink 工具，在輻照度恒定和階躍變化的情況下，對MPPT進(jìn)行了仿真分析。1光伏電池的特性光伏電池實(shí)際上就是一個(gè)大面積平面二極管，其工作可以圖1的單二極管等效電路來描述1，光伏電池的特性方程如式（1）所示。
上傳時(shí)間： 2022-06-21
上傳用戶：
化石能源日趨枯竭，核能發(fā)展受限，能源問題愈來愈成為全人類所不可避免的一個(gè)嚴(yán)峻挑戰(zhàn)。光伏發(fā)電技術(shù)是太陽能利用的主要形式。基于提高太陽能轉(zhuǎn)換效率的最大功率點(diǎn)跟蹤（Maximum power point tracking，簡稱MPPT）的提出與應(yīng)用為光伏發(fā)電系統(tǒng)的優(yōu)化利用提供了堅(jiān)實(shí)的基礎(chǔ)。本文針對MPPT技術(shù)開展了細(xì)致的工作計(jì)劃，完成了以MPPT控制器為核心的光伏發(fā)電系統(tǒng)設(shè)計(jì)和仿真，較好地解決了能量轉(zhuǎn)換低下的問題。首先，總體介紹了光伏發(fā)電系統(tǒng)。其次，闡述了光伏發(fā)電系統(tǒng)基本原理。然后就MPPT控制器的實(shí)現(xiàn)部分-DCDC變換電路，闡述了電路CCM工作模式，利用兩種方法對Buck和Boost電路進(jìn)行了建模和仿真分析.Boost電路設(shè)計(jì)簡便、可升壓，且能夠保證一直工作于CCM下，具有更實(shí)用的特點(diǎn)，更進(jìn)一步地，說明了傳統(tǒng)MPPT算法的實(shí)現(xiàn)原理和控制流程，仿真研究表明改進(jìn)型變步長擾動(dòng)觀察法在光強(qiáng)變化時(shí)具有較好的跟蹤控制性能，但是溫度變化時(shí)跟蹤效果差。針對傳統(tǒng)算改進(jìn)型擾動(dòng)觀察發(fā)法不能很好地響應(yīng)環(huán)境的變化同時(shí)存在嚴(yán)重振蕩，偏差較大的情況，提出一種人工智能控制方法--模糊控制法，進(jìn)行系統(tǒng)分析，模糊控制規(guī)則確定以及FIS編輯器參數(shù)設(shè)置等，完成了系統(tǒng)的設(shè)計(jì)。最后搭建出光伏發(fā)電MPPT人工智能控制系統(tǒng)的仿真模型，設(shè)置相關(guān)參數(shù)。通過仿真結(jié)果的比較和分析驗(yàn)證了模糊控制法的有效性和可行性。
標(biāo)簽： boost電路 mppt 光伏發(fā)電系統(tǒng)
上傳時(shí)間： 2022-06-21
上傳用戶：
The following table covers the main features offered by the MT7628KN and MT7628AN. Overall, the MT7628KN supports the requirements of an entry level AP/router, while the more advanced MT7628AN supports a number of interfaces together with a large maximum RAM capacity.Features· Embedded MIPS24KEc (575/580 MHz) with 64KBl-Cache and 32KB D-Cache·2T2R 2.4GHz with 300 Mbps PHY data rate· Legacy 802.11b/g and HT 802.11n modes·20/40 MHz channel bandwidth· Reverse Data Grant(RDG)· Maximal Ratio Combining(MRC)· Space Time Block Coding(STBC)· MCM 8 Mbytes DDR1 KGD(MT7628KN)·16-bit DDR1/2 up to 128/256 Mbytes(MT7628AN/KN)· SPI/SD-XC/eMMC·x1 USB 2.0 Host,x1 Ple Root Complex·5-port 10/100 FE PHY
標(biāo)簽： mt7628
上傳時(shí)間： 2022-07-25
上傳用戶：
此強(qiáng)而有力的工具將會(huì)增加網(wǎng)站聯(lián)機(jī)速度。它最佳化了操作系統(tǒng)的設(shè)定及連結(jié)。Amplify修改了MTU(Maximum Transmission Unit)、RWIN(Receive Window)，TTL(Time to Live)、PMTU's(Path Maximum Transmission Unit)。這些改改將的減少數(shù)據(jù)處理的分割次數(shù)，可以將資料快速的呈現(xiàn)在使用者面前。
標(biāo)簽：
上傳時(shí)間： 2013-06-29
上傳用戶：eeworm
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