在研究傳統(tǒng)家用燃?xì)鈭缶鞯幕A(chǔ)上,以ZigBee協(xié)議為平臺,構(gòu)建mesh網(wǎng)狀網(wǎng)絡(luò)實現(xiàn)網(wǎng)絡(luò)化的智能語音報警系統(tǒng)。由于傳感器本身的溫度和實際環(huán)境溫度的影響,傳感器標(biāo)定后采用軟件補(bǔ)償方法。為了減少系統(tǒng)費(fèi)用,前端節(jié)點采用半功能節(jié)點設(shè)備,路由器和協(xié)調(diào)器采用全功能節(jié)點設(shè)備,構(gòu)建mesh網(wǎng)絡(luò)所形成的家庭內(nèi)部報警系統(tǒng),通過通用的電話接口連接到外部的公用電話網(wǎng)絡(luò),啟動語音模塊進(jìn)行報警。實驗結(jié)果表明,在2.4 GHz頻率下傳輸,有墻等障礙物的情況下,節(jié)點的傳輸距離大約為35 m,能夠滿足家庭需要,且系統(tǒng)工作穩(wěn)定,但在功耗方面仍需進(jìn)一步改善。
Abstract:
On the basis of studying traditional household gas alarm system, this paper proposed the platform for the ZigBee protocol,and constructed mesh network to achieve network-based intelligent voice alarm system. Because of the sensor temperature and the actual environment temperature, this system design used software compensation after calibrating sensor. In order to reduce system cost, semi-functional node devices were used as front-end node, however, full-function devices were used as routers and coordinator,constructed alarm system within the family by building mesh network,connected to the external public telephone network through the common telephone interface, started the voice alarm module. The results indicate that nodes transmit about 35m in the distance in case of walls and other obstacles by 2.4GHz frequency transmission, this is able to meet family needs and work steadily, but still needs further improvement in power consumption.
為了能夠滿足基站易于選址、優(yōu)質(zhì)快速的建站要求和易維護(hù)、低成本、高可靠的運(yùn)行要求,本文對以方艙來實現(xiàn)一體化結(jié)構(gòu)基站做出一番探討。從系統(tǒng)設(shè)計的觀點闡述了移動通信高性能基站天線設(shè)計的幾個關(guān)鍵問題,介紹了智能天線技術(shù)在基站中的應(yīng)用,并且用HFSS軟件仿真了一種新型的對稱陣子天線,該天線駐波比小于2的帶寬可以達(dá)到60%,具有良好的寬頻帶特性。
Abstract:
In order to meet the station construction requirement of easy site selection and fast base station, and meet the operational requirement of easy maintenance, low cost and high reliability, this paper discussed the unified architecture base station using shelter. Several key problems of high performance mobile communication base station antenna were illustrated from the view of system design, the application of smart antenna in base station was also introduced. And a novel dipole antenna was simulated by using HFSS, the VSWR of the antenna is less than 2, and the bandwidth was reach to 60%. So it has good broadband properties.