Fast Fourier Transform in C
標(biāo)簽： Transform Fourier Fast in
上傳時(shí)間： 2014-01-05
上傳用戶(hù)：lhw888
fast maths routines for delphi/BCB
標(biāo)簽： routines delphi maths fast
上傳時(shí)間： 2014-07-29
上傳用戶(hù)：xg262122
Recent advances in wireless communication technologies have had a transforma- tive impact on society and have directly contributed to several economic and social aspects of daily life. Increasingly, the untethered exchange of information between devices is becoming a prime requirement for further progress, which is placing an ever greater demand on wireless bandwidth. The ultra wideband (UWB) system marks a major milestone in this progress. Since 2002, when the FCC allowed the unlicensed use of low-power, UWB radio signals in the 3.1–10.6GHz frequency band, there has been significant synergistic advance in this technology at the cir- cuits, architectural and communication systems levels. This technology allows for devices to communicate wirelessly, while coexisting with other users by ensuring that its power density is sufficiently low so that it is perceived as noise to other users.
標(biāo)簽： Circuits Wideband Ultra
上傳時(shí)間： 2020-06-01
上傳用戶(hù)：shancjb
In the two years since this book was first published, ultra wideband (UWB) has advanced and consolidated as a technology, and many more people are aware of the possibilities for this exciting technology. We too have expanded and consolidated materials in this second edition in the hope that ‘Ultra Wideband: Signals and Systems in Communication Engineering’ will continue to prove a useful tool for many students and engineers to come to an understanding of the basic technologies for UWB.
標(biāo)簽： Wideband Signals Systems Ultra and
上傳時(shí)間： 2020-06-01
上傳用戶(hù)：shancjb
In this book we focus on the basic signal processing that underlies current and future ultra wideband systems. By looking at signal processing in this way we hope this text will be useful even as UWB applications mature and change or regulations regarding ultra wideband systems are modified. The current UWB field is extremely dynamic, with new techniques and ideas being presented at every communications and signal-processing conference. The basic signal-processing techniques presented in this text though will not change for some time to come. Thus, we have taken a somewhat theoretical approach, which we believe is longer lasting and more useful to the reader in the long term than an up-to-the-minute summary that is out of date as soon as it is published.
標(biāo)簽： Wideband Signals Systems Ultra 1st
上傳時(shí)間： 2020-06-01
上傳用戶(hù)：shancjb
STM32L053C8T6數(shù)據(jù)手冊(cè)Features ? Ultra-low-power platform – 1.65 V to 3.6 V power supply – -40 to 125 °C temperature range – 0.27 μA Standby mode (2 wakeup pins) – 0.4 μA Stop mode (16 wakeup lines) – 0.8 μA Stop mode + RTC + 8 KB RAM retention – 139 μA/MHz Run mode at 32 MHz – 3.5 μs wakeup time (from RAM) – 5 μs wakeup time (from Flash) ? Core: ARM? 32-bit Cortex?-M0+ with MPU – From 32 kHz up to 32 MHz max. – 0.95 DMIPS/MHz ? Reset and supply management – Ultra-safe, low-power BOR (brownout reset) with 5 selectable thresholds – Ultralow power POR/PDR – Programmable voltage detector (PVD) ? Clock sources – 1 to 25 MHz crystal oscillator – 32 kHz oscillator for RTC with calibration – High speed internal 16 MHz factory-trimmed RC (+/- 1%) – Internal low-power 37 kHz RC – Internal multispeed low-power 65 kHz to 4.2 MHz RC – PLL for CPU clock ? Pre-programmed bootloader – USART, SPI supported ? Development support – Serial wire debug supported ? Up to 51 fast I/Os (45 I/Os 5V tolerant) ? Memories – Up to 64 KB Flash with ECC – 8KB RAM – 2 KB of data EEPROM with ECC – 20-byte backup register
標(biāo)簽： stm32l053c8t6
上傳時(shí)間： 2022-02-06
上傳用戶(hù)：
? VL53L1X OverView? VL53L1X Software Package? Default and FAST mode? Ultra light driver.? VL53L1X GUI? VL53L1X Multi sensor design? STM32 FW: Import, Compile, Run, Debug…? What is Xtalk?? Cover Window and ID design? How about Human and object reflectance at 940 nm ?
標(biāo)簽： 激光測(cè)距芯片 stm32
上傳時(shí)間： 2022-07-17
上傳用戶(hù)：bluedrops
元件庫(kù)制作工具，使用 Ultra Librarian 生成各種PCB軟件的器件庫(kù)
上傳時(shí)間： 2013-04-15
上傳用戶(hù)：eeworm
射頻識(shí)別(Radio Frequency Identification，RFID)是一種允許非接觸式數(shù)據(jù)采集的自動(dòng)識(shí)別技術(shù)。其中工作在超高頻(Ultra High Frequency，UHF)頻段的無(wú)源RFID系統(tǒng)，由于在物流與供應(yīng)鏈管理等領(lǐng)域的潛在應(yīng)用，近年來(lái)得到了人們的廣泛關(guān)注。這種系統(tǒng)所使用的無(wú)源標(biāo)簽具有識(shí)別距離長(zhǎng)、體積小、成本低廉等突出特點(diǎn)。目前在市場(chǎng)上出現(xiàn)了各種品牌型號(hào)的UHF RFID無(wú)源標(biāo)簽，由于不同品牌型號(hào)的標(biāo)簽在設(shè)計(jì)與制造工藝上的差異，這些標(biāo)簽在性能表現(xiàn)上各不相同，這就給終端用戶(hù)選擇合適自己應(yīng)用的標(biāo)簽帶來(lái)了困難。RFID基準(zhǔn)測(cè)試就是在實(shí)際部署RFID系統(tǒng)前對(duì)RFID標(biāo)簽的性能進(jìn)行科學(xué)評(píng)估的有效手段。然而為了在常規(guī)實(shí)驗(yàn)室條件下得到準(zhǔn)確公正的測(cè)試結(jié)果，需要對(duì)基準(zhǔn)測(cè)試的性能指標(biāo)及測(cè)試方法學(xué)開(kāi)展進(jìn)一步的研究。本文正是研究符合EPC Class1 Gen2標(biāo)準(zhǔn)的RFID標(biāo)簽基準(zhǔn)測(cè)試。 本文首先分析了當(dāng)前廣泛應(yīng)用的超高頻無(wú)源RFID標(biāo)簽基準(zhǔn)測(cè)試性能指標(biāo)與測(cè)試方法上的局限性與不足之處。例如，在真實(shí)的應(yīng)用環(huán)境中，由于受到各種環(huán)境因素的影響，對(duì)同一品牌型號(hào)的標(biāo)簽，很難得到一致的識(shí)讀距離測(cè)試結(jié)果。另外，在某些測(cè)試場(chǎng)景中，使用識(shí)讀速率作為測(cè)試指標(biāo)，所得到的測(cè)試結(jié)果數(shù)值非常接近，以致分辨度不足以區(qū)分不同品牌型號(hào)標(biāo)簽的性能差異。在這些分析基礎(chǔ)上，本文把路徑損耗引入了RFID基準(zhǔn)測(cè)試，通過(guò)有限點(diǎn)的測(cè)量與數(shù)據(jù)擬合分別得到不同類(lèi)型標(biāo)簽的路徑損耗方程，結(jié)合讀寫(xiě)器天線(xiàn)的輻射方向圖，進(jìn)一步得到各種標(biāo)簽受限于讀寫(xiě)器接收靈敏度的覆蓋區(qū)域。無(wú)源標(biāo)簽由于其被動(dòng)式能量獲取方式，其實(shí)際工作區(qū)域仍然受限于前向鏈路。本文通過(guò)實(shí)驗(yàn)測(cè)試出這些標(biāo)簽的最小激活功率后，得出了各種標(biāo)簽在一定讀寫(xiě)器發(fā)射功率下的激活區(qū)域。完成這些步驟后，根據(jù)這兩種區(qū)域的交集可以確定標(biāo)簽的工作區(qū)域，從而進(jìn)行標(biāo)簽間的比較并達(dá)到基準(zhǔn)測(cè)試的目的，并能找出限制標(biāo)簽工作范圍的瓶頸。 本文最后從功率損耗的角度研究了標(biāo)簽之間的相互干擾，為用戶(hù)在密集部署RFID標(biāo)簽的場(chǎng)景中設(shè)置標(biāo)簽之間的最小間隔距離具有重要的參考意義。
標(biāo)簽： 超高頻 射頻識(shí)別 基準(zhǔn)測(cè)試
上傳時(shí)間： 2013-04-24
上傳用戶(hù)：hbsunhui
隨著數(shù)字電子技術(shù)的發(fā)展，數(shù)字信號(hào)處理廣泛應(yīng)用于聲納、雷達(dá)、通訊語(yǔ)音處理和圖像處理等領(lǐng)域。快速傅立葉變換(Fast Fourier Transform，F(xiàn)FT)在數(shù)字信號(hào)處理系統(tǒng)中起著很重要的作用，F(xiàn)FT 有效地提高了離散傅立葉變換(Discret Fourier Transform，DFT)的運(yùn)算效率。 處理器一般要求具有高速度、高精度、大容量和實(shí)時(shí)處理的性能，而現(xiàn)場(chǎng)可編程門(mén)陣列(Field Programmable Gate Array，F(xiàn)PGA)是近年來(lái)迅速發(fā)展起來(lái)的新型可編程器件，在處理大規(guī)模數(shù)據(jù)方面，有極大的優(yōu)勢(shì)。論文采用了在FPGA中實(shí)現(xiàn)FFT算法的方案。 數(shù)字信號(hào)處理板的硬件電路設(shè)計(jì)是本論文的重要部分之一。在介紹了FFT以及波束形成的基本原理和基本方法的基礎(chǔ)上，根據(jù)實(shí)時(shí)處理的要求，給出了數(shù)字信號(hào)處理板的硬件設(shè)計(jì)方案并對(duì)硬件電路的實(shí)現(xiàn)進(jìn)行了分析和說(shuō)明。 依據(jù)數(shù)字系統(tǒng)的設(shè)計(jì)方法，分別采用基二按時(shí)間抽取FFT算法、基四按時(shí)間抽取FFT算法以及FFT兆核函數(shù)三種方法利用硬件描述語(yǔ)言(VHSICHardware Description Language，VHDL)實(shí)現(xiàn)了1024點(diǎn)的FFT，接著對(duì)三種方法進(jìn)行了評(píng)估，得出了FPGA完全能滿(mǎn)足處理器的實(shí)時(shí)處理的要求的結(jié)論。然后根據(jù)通用串行總線(xiàn)(Universial Serial Bus，USB)協(xié)議，利用VHDL語(yǔ)言編寫(xiě)了USB接口芯片ISP1581的固件程序，實(shí)現(xiàn)了設(shè)備的枚舉過(guò)程。
上傳時(shí)間： 2013-06-27
上傳用戶(hù)：a937518043
蟲(chóng)蟲(chóng)下載站版權(quán)所有 京ICP備2021023401號(hào)-1
