【正文】 沒(méi)有室分系統(tǒng)的樓宇在規(guī)劃建設(shè)室內(nèi)分布系統(tǒng)時(shí)可以將WLAN信號(hào)一同考慮。由于WLAN設(shè)備輸出信號(hào)強(qiáng)度較小，一般采用后端合路，使AP盡量接近天線。共用室內(nèi)分布系統(tǒng)時(shí)天線點(diǎn)位可能不是最優(yōu)的；且由于使用的AP較少，網(wǎng)絡(luò)容量較低。圖10校園網(wǎng)的建設(shè)為管理提供了有效的手段；為教育提供了電子化教學(xué)平臺(tái)；為資源提供了共享的便利；為學(xué)校提供了對(duì)外的窗口。解決這一難題且有效和快速的方法是采用無(wú)線網(wǎng)絡(luò)技術(shù)。 促進(jìn)學(xué)生參與教學(xué)的互動(dòng)性，豐富課程的教學(xué)資源；③ 促進(jìn)教師提高運(yùn)用現(xiàn)代教育信息技術(shù)的操作技能技巧；③ 推進(jìn)學(xué)校信息化、網(wǎng)絡(luò)化、現(xiàn)代化的建設(shè)；④第六章、網(wǎng)絡(luò)通信與信息的安全 學(xué)校對(duì)無(wú)線網(wǎng)絡(luò)的要求集中在：價(jià)格低廉，安裝快捷，具有移動(dòng)性和易用性，支持快速增長(zhǎng)的用戶需求，同時(shí)具備安全性。 當(dāng)用戶試圖連接到網(wǎng)絡(luò)時(shí)，無(wú)線網(wǎng)絡(luò)自動(dòng)分析用戶的網(wǎng)絡(luò)配置，并提供連接，使用戶直接連到網(wǎng)絡(luò)而無(wú)需安裝特殊的軟件并更改自己的網(wǎng)絡(luò)設(shè)置。外部人員可以通過(guò)無(wú)線網(wǎng)絡(luò)繞過(guò)防火墻，對(duì)內(nèi)部網(wǎng)絡(luò)進(jìn)行非授權(quán)存取。第三，網(wǎng)絡(luò)應(yīng)該體現(xiàn)可管理性和可運(yùn)營(yíng)性。根據(jù)本校本單位的實(shí)際情況，適當(dāng)收費(fèi)減輕學(xué)校的資金負(fù)擔(dān)，應(yīng)該是體現(xiàn)在網(wǎng)絡(luò)的先進(jìn)性和運(yùn)營(yíng)性。各移動(dòng)站不僅可以通過(guò)交換中心自行組網(wǎng)，還可以通過(guò)廣域網(wǎng)與遠(yuǎn)地站點(diǎn)組建自己的工作網(wǎng)絡(luò)。此結(jié)構(gòu)的無(wú)線局域網(wǎng)一般使用公用廣播信道，MAC層采用CSMA類(lèi)型的多址接入?yún)f(xié)議。也就是要將多個(gè)AP形成的各自的無(wú)線信號(hào)覆蓋區(qū)域進(jìn)行交叉覆蓋，各覆蓋區(qū)域之間無(wú)縫連接。安裝人員可以通過(guò)地點(diǎn)調(diào)查來(lái)確定AP的位置和數(shù)量。根據(jù)教室和會(huì)議廳的大小，可配置1個(gè)或多個(gè)無(wú)線接入點(diǎn)。該種網(wǎng)絡(luò)的缺點(diǎn)也是因?yàn)槭褂昧巳蛱炀€，波束的全向擴(kuò)散使得功率大大衰減，網(wǎng)絡(luò)傳輸速率低，對(duì)于較遠(yuǎn)距離的遠(yuǎn)端點(diǎn)，網(wǎng)絡(luò)的可靠性不能得到保證。 全向天線：在所有水平方位上信號(hào)的發(fā)射和接收都相等。 根據(jù)實(shí)際情況，校園無(wú)線網(wǎng)絡(luò)應(yīng)用的實(shí)現(xiàn)通常出現(xiàn)在以下這幾個(gè)方面。無(wú)線校園網(wǎng)絡(luò)建設(shè)的工期與校園規(guī)模以及無(wú)線網(wǎng)絡(luò)建設(shè)密度相關(guān)。 網(wǎng)絡(luò)建設(shè)的實(shí)施在通過(guò)效果測(cè)試以后，進(jìn)行設(shè)備選型，根據(jù)實(shí)際情況選擇相應(yīng)的AP、放大器、天線以及其他的輔助設(shè)備進(jìn)行無(wú)線校園網(wǎng)絡(luò)的構(gòu)建。安全監(jiān)控網(wǎng)絡(luò)要求網(wǎng)絡(luò)穩(wěn)定性高、視頻信號(hào)傳輸清晰、網(wǎng)絡(luò)安全性好。從而節(jié)約資源、減輕教師的壓力，從而提高學(xué)校的教學(xué)管理能力。無(wú)線網(wǎng)絡(luò)技術(shù)的應(yīng)用會(huì)越來(lái)越多被人們認(rèn)可并應(yīng)用到實(shí)際學(xué)習(xí)生活中。致 謝在本次論文設(shè)計(jì)過(guò)程中，谷寶榮老師對(duì)該論文從選題，構(gòu)思到最后定稿的各個(gè)環(huán)節(jié)給予細(xì)心指引與教導(dǎo),使我得以最終完成畢業(yè)論文設(shè)計(jì)。參考文獻(xiàn)[1]湯小丹，王侃雅，湯子瀛，1996[2]：人民郵電出版社，2002[3]：華中科技大學(xué)出版社，2002[4]佟震亞，于雪麗等. ：電子工業(yè)出版社，1999[5]，1994[6]郭亮，張輝，1995[7]，1995[8]吳功宜等. ：電子工業(yè)出版社，2007[9]：清華大學(xué)出版社，1994[10]：清華大學(xué)出版社，2008[11](美)James ：機(jī)械工業(yè)出版社，2005[12]（美）Behrouz Chung ：清華大學(xué)出版社，2001[13]Andrew ：清華大學(xué)出版社，1998請(qǐng)刪除以下內(nèi)容，O(∩_∩)O謝謝！?。?The term autism refers to a cluster of conditions appearing early in childhood. All involve severe impairments in social interaction, munication, imaginative abilities, and rigid, repetitive behaviors. To be considered an autistic disorder, some of these impairments must be manifest before the age of three. The reference book used by mental health professionals to diagnose mental disorders is the Diagnostic and Statistical Manual of Mental Disorders , also known as the DSM. The 2000 edition of this reference book (the Fourth Edition Text Revision known as DSMIVTR ) places autism in a category called pervasive developmental disorders . All of these disorders are characterized by ongoing problems with mutual social interaction and munication, or the presence of strange, repetitive behaviors,interests, and activities. People diagnosed with these disorders are affected in many ways for their entire lives. Description Each child diagnosed with an autistic disorder differs from every other, and so general descriptions of autistic behavior and characteristics do not apply equally to every child. Still, the mon impairments in social interaction, munication and imagination, and rigid, repetitive behaviors make it possible to recognize children with these disorders, as they differ markedly from healthy children in many ways. Many parents of autistic children sense that something is not quite right even when their children are infants. The infants may have feeding problems, dislike being changed or bathed, or fuss over any change in routine. They may hold their bodies rigid, making it difficult for parents to cuddle them. Or, they may fail to anticipate being lifted, lying passively while the parent reaches for them, rather than holding their arms up in return. Most parents of autistic children bee aware of the strangeness of these and other behaviors only gradually. Impairments in social interaction are usually among the earliest symptoms to develop. The most mon social impairment is a kind of indifference to other people, or aloofness, even towards parents and close caregivers. The baby may fail to respond to his or her name being called and may show very little facial expression unless extremely angry, upset, or happy. Babies with autism may resist being touched, and appear to be lost in their own world, far from human interaction. Between seven and 10 months of age, most infants often resist being separated from a parent or wellknown caregiver, but these infants may show no disturbance when picked up by a stranger. Other children with autism may be very passive, although less resistant to efforts by others to interact. However, they do not initiate social interaction themselves. Still others may attempt to engage with adults and peers, but in ways that strike others as inappropriate, or odd. In adolescence and adulthood, some of the higherfunctioning individuals with autistic disorders may appear overly formal and polite. They may react with little spontaneity, as if social interaction doesn39。s games measures in (7576 cm) in circumference, and a women39。s five basic principles center on the ball, which was described as large, light, and handled with the hands. Players could not move the ball by running alone, and none of the players was restricted against handling the ball. The playing area was also open to all players, but there was to be no physical contact between players。 England in 1894。s basketball. Until World War II, basketball became increasingly popular in the United States especially at the high school and college levels. After World War II, its popularity grew around the world. In the 1980s, interest in the game truly exploded because of television exposure. Broadcast of the NCAA Championship Games began in 1963, and, by the 1980s, cable television was carrying regular season college games and even high school championships in some states. 23