Abstract: This application note describes system-level characterization and modeling techniques for radio frequency (RF) and microwavesubsystem components. It illustrates their use in a mixed-signal, mixed-mode system-level simulation. The simulation uses an RF transmitterwith digital predistortion (DPD) as an example system. Details of this complex system and performance data are presented.
標(biāo)簽: 射頻 仿真 微波系統(tǒng) 建模
上傳時(shí)間: 2013-12-18
上傳用戶:onewq
ALC(Automatic level control自動(dòng)電平控制)是直放站系統(tǒng)中極為重要的一環(huán),它是指當(dāng)放大器輸出信號(hào)電平到達(dá)ALC設(shè)定值時(shí),增加輸入信號(hào)電平,放大器對(duì)輸出信號(hào)電平的控制能力。
上傳時(shí)間: 2013-11-02
上傳用戶:hasan2015
針對(duì)UHF讀寫器設(shè)計(jì)中,在符合EPC Gen2標(biāo)準(zhǔn)的情況下,對(duì)標(biāo)簽返回的高速數(shù)據(jù)進(jìn)行正確解碼以達(dá)到正確讀取標(biāo)簽的要求,提出了一種新的在ARM平臺(tái)下采用邊沿捕獲統(tǒng)計(jì)定時(shí)器數(shù)判斷數(shù)據(jù)的方法,并對(duì)FM0編碼進(jìn)行解碼。與傳統(tǒng)的使用定時(shí)器定時(shí)采樣高低電平的FM0解碼方法相比,該解碼方法可以減少定時(shí)器定時(shí)誤差累積的影響;可以將捕獲定時(shí)器數(shù)中斷與數(shù)據(jù)判斷解碼相對(duì)分隔開,使得中斷對(duì)解碼影響很小,實(shí)現(xiàn)捕獲與解碼的同步。通過實(shí)驗(yàn)表明,這種方法提高了解碼的效率,在160 Kb/s的接收速度下,讀取一張標(biāo)簽的時(shí)間約為30次/s。 Abstract: Aiming at the requirement of receiving correctly decoded data from the tag under high-speed communication which complied with EPC Gen2 standard in the design of UHF interrogator, the article introduced a new technology for FM0 decoding which counted the timer counter to judge data by using the edge interval of signal capture based on the ARM7 platform. Compared with the traditional FM0 decoding method which used the timer timed to sample the high and low level, the method could reduce the accumulation of timing error and could relatively separate capture timer interrupt and the data judgment for decoding, so that the disruption effect on the decoding was small and realizd synchronization of capture and decoding. Testing result shows that the method improves the efficiency of decoding, at 160 Kb/s receiving speed, the time of the interrogator to read a tag is about 30 times/s.
標(biāo)簽: UHF FM0 讀寫器 解碼技術(shù)
上傳時(shí)間: 2013-11-10
上傳用戶:liufei
同步技術(shù)是跳頻通信系統(tǒng)的關(guān)鍵技術(shù)之一,尤其是在快速跳頻通信系統(tǒng)中,常規(guī)跳頻通信通過同步字頭攜帶相關(guān)碼的方法來實(shí)現(xiàn)同步,但對(duì)于快跳頻來說,由于是一跳或者多跳傳輸一個(gè)調(diào)制符號(hào),難以攜帶相關(guān)碼。對(duì)此引入雙跳頻圖案方法,提出了一種適用于快速跳頻通信系統(tǒng)的同步方案。采用短碼攜帶同步信息,克服了快速跳頻難以攜帶相關(guān)碼的困難。分析了同步性能,仿真結(jié)果表明該方案同步時(shí)間短、虛警概率低、捕獲概率高,同步性能可靠。 Abstract: Synchronization is one of the key techniques to frequency-hopping communication system, especially in the fast frequency hopping communication system. In conventional frequency hopping communication systems, synchronization can be achieved by synchronization-head which can be used to carry the synchronization information, but for the fast frequency hopping, Because modulation symbol is transmitted by per hop or multi-hop, it is difficult to carry the correlation code. For the limitation of fast frequency hopping in carrying correlation code, a fast frequency-hopping synchronization scheme with two hopping patterns is proposed. The synchronization information is carried by short code, which overcomes the difficulty of correlation code transmission in fast frequency-hopping. The performance of the scheme is analyzed, and simulation results show that the scheme has the advantages of shorter synchronization time, lower probability of false alarm, higher probability of capture and more reliable of synchronization.
標(biāo)簽: 快速跳頻 同步技術(shù) 通信系統(tǒng)
上傳時(shí)間: 2013-11-23
上傳用戶:mpquest
The LPC1850/30/20/10 are ARM Cortex-M3 based microcontrollers for embeddedapplications. The ARM Cortex-M3 is a next generation core that offers systemenhancements such as low power consumption, enhanced debug features, and a highlevel of support block integration.The LPC1850/30/20/10 operate at CPU frequencies of up to 150 MHz. The ARMCortex-M3 CPU incorporates a 3-stage pipeline and uses a Harvard architecture withseparate local instruction and data buses as well as a third bus for peripherals. The ARMCortex-M3 CPU also includes an internal prefetch unit that supports speculativebranching.The LPC1850/30/20/10 include up to 200 kB of on-chip SRAM data memory, a quad SPIFlash Interface (SPIFI), a State Configuration Timer (SCT) subsystem, two High-speedUSB controllers, Ethernet, LCD, an external memory controller, and multiple digital andanalog peripherals.
標(biāo)簽: Cortex-M 1850 LPC 內(nèi)核微控制器
上傳時(shí)間: 2014-12-31
上傳用戶:zhuoying119
The LPC4350/30/20/10 are ARM Cortex-M4 based microcontrollers for embeddedapplications. The ARM Cortex-M4 is a next generation core that offers systemenhancements such as low power consumption, enhanced debug features, and a highlevel of support block integration.The LPC4350/30/20/10 operate at CPU frequencies of up to 150 MHz. The ARMCortex-M4 CPU incorporates a 3-stage pipeline, uses a Harvard architecture withseparate local instruction and data buses as well as a third bus for peripherals, andincludes an internal prefetch unit that supports speculative branching. The ARMCortex-M4 supports single-cycle digital signal processing and SIMD instructions. Ahardware floating-point processor is integrated in the core.The LPC4350/30/20/10 include an ARM Cortex-M0 coprocessor, up to 264 kB of datamemory, advanced configurable peripherals such as the State Configurable Timer (SCT)and the Serial General Purpose I/O (SGPIO) interface, two High-speed USB controllers,Ethernet, LCD, an external memory controller, and multiple digital and analog peripherals
上傳時(shí)間: 2013-10-28
上傳用戶:15501536189
本軟件是關(guān)于MAX338, MAX339的英文數(shù)據(jù)手冊(cè):MAX338, MAX339 8通道/雙4通道、低泄漏、CMOS模擬多路復(fù)用器 The MAX338/MAX339 are monolithic, CMOS analog multiplexers (muxes). The 8-channel MAX338 is designed to connect one of eight inputs to a common output by control of a 3-bit binary address. The dual, 4-channel MAX339 is designed to connect one of four inputs to a common output by control of a 2-bit binary address. Both devices can be used as either a mux or a demux. On-resistance is 400Ω max, and the devices conduct current equally well in both directions. These muxes feature extremely low off leakages (less than 20pA at +25°C), and extremely low on-channel leakages (less than 50pA at +25°C). The new design offers guaranteed low charge injection (1.5pC typ) and electrostatic discharge (ESD) protection greater than 2000V, per method 3015.7. These improved muxes are pin-compatible upgrades for the industry-standard DG508A and DG509A. For similar Maxim devices with lower leakage and charge injection but higher on-resistance, see the MAX328 and MAX329.
上傳時(shí)間: 2013-11-12
上傳用戶:18711024007
It would not be an exaggeration to say that semiconductor devices have transformed humanlife. From computers to communications to internet and video games these devices and the technologies they have enabled have expanded human experience in a way that is unique in history. Semiconductor devices have exploited materials, physics and imaginative applications to spawn new lifestyles. Of course for the device engineer, in spite of the advances, the challenges of reaching higher frequency, lower power consumption, higher power generation etc.
標(biāo)簽: 半導(dǎo)體器件 物理
上傳時(shí)間: 2013-10-28
上傳用戶:songnanhua
The super-junction structure, which has P-type pillar layers as shown left, realizes high withstand voltage and ON-resistance lower than the conventional theoretical limit of silicon.
標(biāo)簽: 場(chǎng)效應(yīng)管 產(chǎn)品指南
上傳時(shí)間: 2014-12-31
上傳用戶:qwer0574
AI :Auto-Insertion 自動(dòng)插件 AQL :acceptable quality level 允收水準(zhǔn) ATE :automatic test equipment 自動(dòng)測(cè)試 ATM :atmosphere 氣壓 BGA :ball grid array 球形矩陣
標(biāo)簽: SMT 術(shù)語 中英文 對(duì)比
上傳時(shí)間: 2013-11-20
上傳用戶:haoxiyizhong
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