甚高頻率 的英文怎麼說
中文拼音 [shégāobīnlǜ]
甚高頻率
英文
very high frequency （vhf）-
Mixers are the key components of many microwave and millimeter - wave systems. the super - heterodyne receiver is always applied in modern communication system, mixer becomes the key component as is at the first part of system. but it is more and more difficult to get the choiceness lo source of the same band with the system is working at high frequency especially in the millimeter - wave. sub - harmonic mixer is a good solution to this problem now. in this circuit we need just half 、 quarter 、 even 1 / 8 of the rf signal frequency. in this paper the design and fabricate of sub - harmonic hmic mixers ( 2, 4 ) at w - band are introduced
混頻器是微波通信、射電天文學、雷達、等離子物理、遙控、遙感、電子對抗，以及許多微波測量系統中至關重要的部件。在現代通信系統中，毫米波頻段通常採用超外差接收機，混頻器作為第一級就成為關鍵部件。由於在毫米波頻段，同頻段高性能的本振源成本高，技術難度大，採用分諧波混頻技術是解決此問題的有效途徑，只需射頻頻率1 / 2 、 1 / 4甚至1 / 8的本振頻率即可實現混頻。Malfunctions can be diagnosed using infrared thermography without affecting the work state of tested equipments, thus the diagnostic accuracy can be improved. infrared thermography, just as often, improves electronic fault diagnosis by isolating the malfunction to specific areas of the circuit board, what is more, it usually does point directly to the failing component. thermography even can rapidly diagnose up to hundreds of elements on one pcb at one time, without requiring the operator to know the circuit principle very well, which can reduce the workload greatly
紅外故障檢測儀可以對電子設備進行在線測量，檢測時不會影響待測設備的正常工作和頻率特性，這對高頻電路的檢測尤其方便，且能提高診斷的準確性;他通常能指出電路板上的故障區域，甚至經常能直接找出故障元器件，這樣就提高了維修質量;並且能在不需要檢測人員對電路原理有深入理解和分析的情況下，對同一塊電路板上的數十隻甚至數百隻器件同時進行快速診斷，這就大大減少了維修人員的工作量，提高了維修人員的工作效率。H. 26l / h. 264 is a new video compression standard provided by itu - t and iso / iec, which faces to very low rate video communication. it uses a new dct transform method as 4 * 4 integer dct. it can reduce block effect, while it is clear and easy to realizen, has high precision, computes fast and costs less memory
H . 26l / h . 264是itu - t與iso / iec聯合提出的一種較新的面向甚低碼率視頻通信應用的視頻圖像壓縮標準，採用了一些新的編碼技術，使用了新的dct變換方法: 4 4整型dct變換，該變換具有減小方塊效應，演算法明晰簡單、易於實現，運算結果精度高且不會溢出，運算速度快，佔用內存小等優點。Gyrotron is a new and important type of electrical microwave device from 50th years of last century to current. as a high power resource, it can produce and amplify milimeter and submilimeter - wave radiation at high frequency
迴旋管是20世紀50年代後期發展起來的一類新型微波電子器件，它能在毫米甚至亞毫米波段產生或者通過放大得到大功率微波輻射，並具有相當高的工作頻率。But modern electronic counterwork technic could exactly estimate the carrier frequency, signal period, even the pseudo - random ( pn ) sequence itself of direct sequence spread spectrum ( dsss ). it is urgency to investigate a new dsss to achieve lower probability of detection ( lpd ) and higher anti - jamming
然而現代電子對抗技術可以準確估計直接序列擴頻通信的載波頻率、符號周期甚至擴頻碼本身，為達到更低截獲率和更高抗干擾的通信目的，必須研究新的直擴通信技術。25 zhang b, shirazi m n. implementation of explicit wireless loss notification using mac - layer information. in proc. ieee wireless communications and networking conference, vol. 2, new orleans, usa, march 2003, pp. 1339 - 1343
1易損耗的無線通道導致了高比特誤碼率，從而引發數據包錯誤甚至無法恢復，發送端就誤認為網路擁塞，導致頻繁進入慢啟動，造成tcp性能下降。Service charges for use of the very high frequency communications facilities and secondary surveillance radar data to enhance safety and improve operational efficiency
租用甚高頻通訊設備及二次監察雷達數據的服務費用以加強飛行安全及運作效率H. 263 + is one of the mature standards to deal with high compress rate and strong channel error correction ability, which could be perfectly used in wireless video communication areas
面向甚低碼率的h . 263 +標準則是能較好地解決高壓縮效率和強通道冗錯能力的成熟標準之一，能較好地應用於無線視頻通信領域。Avalanche diode is the traditional solid device to obtain millimeter wave source. the high order frequency multiply technology of avalanche diode is reported very scarcely
雪崩二極體是傳統的毫米波固態功率源器件，但利用雪崩二極體實現高次倍頻的研究卻報道甚少。分享友人