描述
無(wú)線發(fā)射器和接收器在概念上,可分為基頻與射頻兩個(gè)部份。基頻包含發(fā)射器的輸入信號(hào)之頻率范圍,也包含接收器的輸出信號(hào)之頻率范圍?;l的頻寬決定了數(shù)據(jù)在系統(tǒng)中可流動(dòng)的基本速率?;l是用來(lái)改善數(shù)據(jù)流的可靠度,并在特定的數(shù)據(jù)傳輸率之下,減少發(fā)射器施加在傳輸媒介(transmissionmedium)的負(fù)荷。因此,PCB設(shè)計(jì)基頻電路時(shí),需要大量的信號(hào)處理工程知識(shí)。發(fā)射器的射頻電路能將已處理過(guò)的基頻信號(hào)轉(zhuǎn)換、升頻至指定的頻道中,并將此信號(hào)注入至傳輸媒體中。相反的,接收器的射頻電路能自傳輸媒體中取得信號(hào),并轉(zhuǎn)換、降頻成基頻。
發(fā)射器有兩個(gè)主要的PCB設(shè)計(jì)目標(biāo):第一是它們必須盡可能在消耗最少功率的情況下,發(fā)射特定的功率。第二是它們不能干擾相鄰頻道內(nèi)的收發(fā)機(jī)之正常運(yùn)作。就接收器而言,有三個(gè)主要的PCB設(shè)計(jì)目標(biāo):首先,它們必須準(zhǔn)確地還原小信號(hào);第二,它們必須能去除期望頻道以外的干擾信號(hào);最后一點(diǎn)與發(fā)射器一樣,它們消耗的功率必須很小。
歐美品牌停產(chǎn)的“DCS系統(tǒng)備品備件
歐美品牌常用的“DCS系統(tǒng)備品備件
歐美品牌停產(chǎn)的,常用的“PLC”備品備件
我司產(chǎn)品應(yīng)用于以下領(lǐng)域:
1,《發(fā)電廠DCS監(jiān)控系統(tǒng)》
2,《智能平鋼化爐系統(tǒng)制造》
3,《PLC可編程輸送控制系統(tǒng)》
4,《DCS集散控制系統(tǒng)》
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5,《智能型消防供水控制系統(tǒng)》
6,《化工廠藥液恒流量計(jì)算機(jī)控制系統(tǒng)》
7,《電氣控制系統(tǒng)》造紙,印染生產(chǎn)線,變電站綜合自動(dòng)化控制系列
本特利,英維思,伍德沃德,??怂共_、西屋、瑞恩、施耐德莫迪康、ABB、AB、西門子、摩托羅拉、GE發(fā)那科、安川、博世力士樂(lè),ACSO,力士樂(lè)等各大品牌的DCS系統(tǒng)配件,機(jī)器人系統(tǒng)配件,大型伺服系統(tǒng)備件。
Dell M610 96GB Memory Kit DDR3 PC3-8500R RAM (12 X 8GB)
Dell R710 96GB Memory Kit DDR3 PC3-8500R RAM (12 X 8GB)
Dell T710 96GB Memory Kit DDR3 PC3-8500R RAM (12 X 8GB)
Dell M710 96GB Memory Kit DDR3 PC3-8500R RAM (12 X 8GB)
Dell T610 96GB Memory Kit DDR3 PC3-8500R RAM (12 X 8GB)
Dell R610 96GB Memory Kit DDR3 PC3-8500R RAM (12 X 8GB)
Dell R710 112GB Memory Kit DDR3 PC3-8500R RAM (14x8GB)
Dell M1000e 8 x M710 Dual Xeon X5650 32GB RAM 2x300GB
Dell M1000e 8 x M710 Dual Xeon X5650 64GB RAM 2x300GB
Dell M1000e 8 x M710 Dual Xeon X5650 96GB RAM 2x300GB
Dell M1000e 8 x M710 Dual Xeon X5650 144GB RAM 2x300GB
Dell M1000e 8 x M710 Dual Xeon X5650 32GB RAM 4x300GB
Dell M1000e 8 x M710 Dual Xeon X5650 64GB RAM 4x300GB
Dell M1000e 8 x M710 Dual Xeon X5650 96GB RAM 4x300GB
Dell M1000e 8 x M710 Dual Xeon X5650 144GB RAM 4x300GB
Dell M1000e 8 x M710 Dual Xeon X5650 32GB RAM 2x146GB
Dell M1000e 8 x M710 Dual Xeon X5650 64GB RAM 2x146GB
Dell M1000e 8 x M710 Dual Xeon X5650 96GB RAM 2x146GB
Dell M1000e 8 x M710 Dual Xeon X5650 144GB RAM 2x146GB
Dell M1000e 8 x M710 Dual Xeon X5650 32GB RAM 4x146GB
Dell M1000e 8 x M710 Dual Xeon X5650 64GB RAM 4x146GB
Dell M1000e 8 x M710 Dual Xeon X5650 96GB RAM 4x146GB
Dell M1000e 8 x M710 Dual Xeon X5650 144GB RAM 4x146GB
Dell M1000e 8 x M710 Dual Xeon L5640 32GB RAM 2x300GB
Dell M1000e 8 x M710 Dual Xeon L5640 64GB RAM 2x300GB
Dell M1000e 8 x M710 Dual Xeon L5640 96GB RAM 2x300GB
Dell M1000e 8 x M710 Dual Xeon L5640 144GB RAM 2x300GB
Dell M1000e 8 x M710 Dual Xeon L5640 32GB RAM 4x300GB
Dell M1000e 8 x M710 Dual Xeon L5640 64GB RAM 4x300GB
Dell M1000e 8 x M710 Dual Xeon L5640 96GB RAM 4x300GB
Dell M1000e 8 x M710 Dual Xeon L5640 144GB RAM 4x300GB
Dell M1000e 8 x M710 Dual Xeon L5640 32GB RAM 2x146GB
Dell M1000e 8 x M710 Dual Xeon L5640 64GB RAM 2x146GB
Dell M1000e 8 x M710 Dual Xeon L5640 96GB RAM 2x146GB
Dell M1000e 8 x M710 Dual Xeon L5640 144GB RAM 2x146GB
Dell M1000e 8 x M710 Dual Xeon L5640 32GB RAM 4x146GB
HP BL490 G6 Intel Xeon E5504 2.0GHZ CPU Kit 509327-B21
Dell M1000e 8 x M710 Dual Xeon L5640 64GB RAM 4x146GB
Dell M1000e 8 x M710 Dual Xeon L5640 96GB RAM 4x146GB
Dell M1000e 8 x M710 Dual Xeon L5640 144GB RAM 4x146GB
HP BL490 G6 Intel Xeon X5570 2.93GHZ CPU Kit 509319-B21
Dell M1000e 4 x M710 Dual Xeon X5650 32GB RAM 2x300GB
Dell M1000e 4 x M710 Dual Xeon X5650 64GB RAM 2x300GB
Dell M1000e 4 x M710 Dual Xeon X5650 96GB RAM 2x300GB
Dell M1000e 4 x M710 Dual Xeon X5650 144GB RAM 2x300GB
Dell M1000e 4 x M710 Dual Xeon X5650 32GB RAM 4x300GB
Dell M1000e 4 x M710 Dual Xeon X5650 64GB RAM 4x300GB
Dell M1000e 4 x M710 Dual Xeon X5650 96GB RAM 4x300GB
Dell M1000e 4 x M710 Dual Xeon X5650 144GB RAM 4x300GB
Dell M1000e 4 x M710 Dual Xeon X5650 32GB RAM 2x146GB
Dell M1000e 4 x M710 Dual Xeon X5650 64GB RAM 2x146GB
Dell M1000e 4 x M710 Dual Xeon X5650 96GB RAM 2x146GB
Dell M1000e 4 x M710 Dual Xeon X5650 144GB RAM 2x146GB
Dell M1000e 4 x M710 Dual Xeon X5650 32GB RAM 4x146GB
Dell M1000e 4 x M710 Dual Xeon X5650 64GB RAM 4x146GB
Dell M1000e 4 x M710 Dual Xeon X5650 96GB RAM 4x146GB
Dell M1000e 4 x M710 Dual Xeon X5650 144GB RAM 4x146GB
Dell M1000e 4 x M710 Dual Xeon L5640 32GB RAM 2x300GB
Dell M1000e 4 x M710 Dual Xeon L5640 64GB RAM 2x300GB
Dell M1000e 4 x M710 Dual Xeon L5640 96GB RAM 2x300GB
Dell M1000e 4 x M710 Dual Xeon L5640 144GB RAM 2x300GB
Dell M1000e 4 x M710 Dual Xeon L5640 32GB RAM 4x300GB
Dell M1000e 4 x M710 Dual Xeon L5640 64GB RAM 4x300GB
Dell M1000e 4 x M710 Dual Xeon L5640 96GB RAM 4x300GB
Dell M1000e 4 x M710 Dual Xeon L5640 144GB RAM 4x300GB
Dell M1000e 4 x M710 Dual Xeon L5640 32GB RAM 2x146GB
Dell M1000e 4 x M710 Dual Xeon L5640 64GB RAM 2x146GB
Dell M1000e 4 x M710 Dual Xeon L5640 96GB RAM 2x146GB
Dell M1000e 4 x M710 Dual Xeon L5640 144GB RAM 2x146GB
Dell M1000e 4 x M710 Dual Xeon L5640 32GB RAM 4x146GB
Dell M1000e 4 x M710 Dual Xeon L5640 64GB RAM 4x146GB
Dell M1000e 4 x M710 Dual Xeon L5640 96GB RAM 4x146GB