發(fā)布時(shí)間：2018-01-09 03:02

  本文關(guān)鍵詞：基于復(fù)合熱敏電阻材料的溫補(bǔ)衰減器　出處：《電子科技大學(xué)》2016年碩士論文　論文類(lèi)型：學(xué)位論文

  更多相關(guān)文章： 溫補(bǔ)衰減器 NTC電阻 PTC電阻 電阻溫度系數(shù) 衰減量變化

【摘要】：在現(xiàn)代微波通信領(lǐng)域,低噪放(LNA)和功放(PA)系統(tǒng)的增益、輸出功率和電壓駐波比等主要射頻指標(biāo)隨溫度變化而變化。一般而言,當(dāng)溫度越高/越低時(shí),系統(tǒng)的輸出功率及增益將會(huì)越小/越大,則系統(tǒng)的輸出功率及增益將隨溫度變化,導(dǎo)致系統(tǒng)指標(biāo)受到嚴(yán)重影響。因此需要在射頻系統(tǒng)中加入一種溫度補(bǔ)償?shù)脑?即溫補(bǔ)衰減器。溫補(bǔ)衰減器通過(guò)電阻性厚膜材料來(lái)吸收功率從而轉(zhuǎn)化為熱量以實(shí)現(xiàn)衰減。當(dāng)溫度升高/降低時(shí),溫補(bǔ)衰減器的衰減量將減少/增大,補(bǔ)償高頻放大電路中增益隨溫度變化而減小/增大的特性。為實(shí)現(xiàn)更好的溫度補(bǔ)償特性,需要通過(guò)二種不同熱敏特性的電阻的復(fù)合來(lái)設(shè)計(jì)溫補(bǔ)衰減器。本論文從材料研制、器件仿真設(shè)計(jì)以及器件的制備與測(cè)試方面,主要做了以下三方面的工作來(lái)探索基于復(fù)合熱敏電阻材料的溫補(bǔ)衰減器的研究。材料研制方面,首先研究了NTC電阻LSMO材料的性能,測(cè)得其電阻平均膜厚為13.5μm,室溫(25℃)電阻率為0.249Ω?cm,在-20℃~+120℃溫度范圍內(nèi),TCR為-2839.11 ppm/℃;在10℃~+120℃范圍內(nèi),TCR達(dá)到-3602.3 ppm/℃,并對(duì)其進(jìn)行了SEM測(cè)試和分析。然后摻雜0.05%-0.5%幾個(gè)不同比例的Y2O3到BST材料中,研究鈦酸鋇系PTC電阻材料的性能。在-20℃~+120℃的溫度范圍內(nèi),摻Y(jié)的BST材料的電阻值基本隨溫度升高而增大,呈現(xiàn)出PTC電阻特性。在一定摻雜濃度下,電阻材料的室溫電阻率與摻雜濃度存在U型曲線關(guān)系。對(duì)于摻雜Y0.0045的BST圓片樣品,保溫30 min時(shí),樣品有最低室溫電阻率,為7.58kΩ?cm,TCR為6.34×104 ppm/℃;當(dāng)保溫60 min時(shí),室溫電阻率為13 kΩ?cm,TCR為1.24×105 ppm/℃,并對(duì)樣品進(jìn)行了XRD及SEM測(cè)試和分析。溫補(bǔ)衰減器的設(shè)計(jì)方面,根據(jù)π型衰減器模型,通過(guò)熱敏電阻的并聯(lián)思想,采用不同輸入輸出端口形狀的50Ω阻抗匹配,利用HFSS仿真軟件設(shè)計(jì)了室溫衰減量為-7 dB的,單段連續(xù)、二段不連續(xù)、三段不連續(xù)的三種不同輸入輸出端口模型的π型溫補(bǔ)衰減器。溫補(bǔ)衰減器的制備與測(cè)試方面,通過(guò)絲印工藝,將NTC和PTC電阻通過(guò)網(wǎng)版印刷在氧化鋁基片上,并制作了測(cè)試用夾具,然后利用矢網(wǎng)和高低溫箱測(cè)試其微波性能。其中三種模型的工作頻率分別為:DC-3 GHz、DC-4 GHz、DC-6 GHz,在該頻率范圍內(nèi),其VSWR均小于2,S11均小于-10 dB。在-20℃~+85℃的溫度范圍內(nèi),三者的衰減量變化量均為1.25 dB左右,衰減量變化率為-0.0017dB/dB/℃左右。對(duì)三種模型都加載了一小時(shí)的功率測(cè)試,其承載功率大小為2 W,測(cè)得厚膜電阻表面最高溫度均低于100℃,低于極限溫度125℃,符合設(shè)計(jì)要求。
[Abstract]:In modern microwave communication field, low noise amplifier (LNA) and power amplifier (PA) gain of the system, the main indicators of RF output power and voltage in Bobbi with temperature changes. In general, when the temperature is higher / lower, the output power and gain system will be smaller / larger output power. And gain system will change with temperature, causing the system index has been seriously affected. Therefore need to add a temperature compensation in RF system components, namely temperature compensated attenuator. Temperature compensated attenuator by resistive thick film material to absorb power is transformed into heat to achieve attenuation. When the temperature increase / decrease, the decrement of temperature fill the attenuator will reduce / increase compensation for high frequency amplifier circuit gain change with temperature decreasing / increased characteristics. To realize temperature compensation characteristics better, through two different thermal properties of the composite design of temperature resistance Fill the attenuator. In this thesis, material design, fabrication and testing device design and simulation device system, mainly from the following three aspects to study composite thermistor material temperature compensated attenuator. Based on material research, firstly studies the performance of the NTC resistance of LSMO material, measured the resistance of average film thickness 13.5 m, at room temperature (25 DEG C) resistivity 0.249? Cm, -20 at ~+120 DEG C temperature range of TCR to -2839.11 ppm/ at 10 DEG ~+120 DEG C; in the range of TCR to -3602.3, ppm/ C, and has carried on the SEM test and analysis. Then several different proportion of Y2O3 doped 0.05%-0.5% to BST materials, properties of barium titanate PTC resistance material. The temperature range of -20 DEG ~+120 DEG C, the resistance of Y doped BST material value increases with the temperature rise, showing a PTC resistance. In a certain doping concentration, resistance at room temperature There is U shape relationship between resistivity and doping concentration for BST wafer samples doped with Y0.0045, holding 30 min, samples have the lowest resistivity at room temperature, 7.58k. Cm, TCR? 6.34 x 104 ppm/ C; when the insulation of 60 min, the room temperature resistivity of 13 K cm, TCR 1.24 Omega? * 105 ppm/ C, the samples were tested by XRD and SEM test and analysis. The design of temperature compensated attenuator, PI type attenuator according to the model, the idea of parallel thermistor, matching with 50 ohm impedance different input and output port shape, using the HFSS simulation software design of room temperature attenuation of -7 dB, a single continuous. The two section is not continuous, PI Wen three discontinuous segments of three different input and output port model complement attenuator. Preparation and testing temperature compensated attenuator system, through the screen printing process, NTC and PTC resistance by screen printing on alumina substrates, and made the test fixture, however After the use of vector network and low temperature test box. The working frequency of the microwave absorption properties of three kinds of models are: DC-3 GHz, DC-4 GHz, DC-6 GHz, in the frequency range, the VSWR were less than 2, S11 less than -10 dB. in the temperature range of -20 DEG ~+85 DEG C, the attenuation variation three who was about 1.25 dB, the attenuation rate is -0.0017dB/dB/ degrees Celsius. The three models are loaded with power one hour test, the power load size is 2 W, the measured maximum temperature of the surface of the thick film resistor are lower than 100 DEG C, below a critical temperature of 125 DEG C, meet the design requirements.

【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2016
【分類(lèi)號(hào)】：TN715

【參考文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前3條

1 張鵬;Ti摻雜TaN薄膜與微波衰減器研究[D];電子科技大學(xué);2015年

2 崔新;MMIC衰減器的設(shè)計(jì)與研究[D];蘭州交通大學(xué);2014年

3 鄭權(quán);PTC配方與工藝研究[D];電子科技大學(xué);2011年

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本文編號(hào)：1399702