電話[英語(yu)(yu)：Telephone，出自希臘語(yu)(yu)τ?λε（tēle，意為(wei)“遠(yuan)”）和φων?（phōnē，意為(wei)“聲(sheng)音(yin)(yin)(yin)”），舊(jiu)譯德律風]是(shi)一種可(ke)以(yi)傳(chuan)送與接收聲(sheng)音(yin)(yin)(yin)的(de)遠(yuan)程通(tong)信設備。早在18世紀歐(ou)洲已有“電話”一詞(ci)，用(yong)來指(zhi)用(yong)線(xian)串(chuan)成的(de)話筒（以(yi)線(xian)串(chuan)起(qi)杯子）。電話的(de)出現要歸功(gong)于(yu)亞歷(li)山(shan)大·格拉漢姆·貝(bei)爾，早期電話機的(de)原(yuan)理為(wei)：說話聲(sheng)音(yin)(yin)(yin)為(wei)空氣里(li)的(de)復合振動，可(ke)傳(chuan)輸到固體上，通(tong)過電脈(mo)沖于(yu)導電金屬上傳(chuan)遞。貝(bei)爾于(yu)1876年3月(yue)申請了電話的(de)專(zhuan)利權。
美國國會2002年6月15日269號決(jue)議確認安東(dong)尼奧·穆齊為電話的(de)(de)發明(ming)人。穆齊于1860年首次(ci)向公眾展示了(le)他的(de)(de)發明(ming)，并在紐約(yue)的(de)(de)意大利語(yu)報紙(zhi)上發表了(le)關于這項發明(ming)的(de)(de)介(jie)紹。
歷史上對(dui)電話(hua)的改進和(he)發(fa)明包(bao)括：碳粉(fen)話(hua)筒、人工交(jiao)換板、撥號(hao)盤、自動電話(hua)交(jiao)換機、程(cheng)控電話(hua)交(jiao)換機、雙音多頻(pin)撥號(hao)、語音數(shu)字采樣等。近年來(lai)的新技(ji)術包(bao)括：ISDN、DSL、網絡電話(hua)、模擬移(yi)動電話(hua)和(he)數(shu)字移(yi)動電話(hua)等。
這(zhe)一(yi)行業通常分(fen)為電話設備制造(zao)商(shang)和電話網(wang)絡(luo)運(yun)營商(shang)。在(zai)歷史上，網(wang)絡(luo)運(yun)營商(shang)通常都擁有全國性(xing)的(de)(de)壟(long)斷(duan)。近年(nian)來，隨著全球電信市場的(de)(de)開放和集成以(yi)及技術(shu)的(de)(de)發展，逐漸出(chu)現(xian)多家運(yun)營商(shang)在(zai)同一(yi)市場競爭的(de)(de)局面。例如，貝爾系統，即(ji)AT&T的(de)(de)下(xia)屬公(gong)司曾擁有美國電話市場的(de)(de)80%。1984年(nian)，由于美國司法部反壟(long)斷(duan)訴訟，貝爾系統被(bei)迫分(fen)區(qu)成多個獨(du)立的(de)(de)地方貝爾公(gong)司。有一(yi)個說法可(ke)以(yi)說明這(zhe)個現(xian)象(xiang)：在(zai)AT&T未分(fen)區(qu)前，IBM是美國第二(er)大公(gong)司。在(zai)AT&T分(fen)區(qu)成七個公(gong)司后，IBM的(de)(de)排名變成第八名。
電話(hua)(hua)機(ji)是(shi)通(tong)過電信號(hao)雙向傳輸話(hua)(hua)音的終(zhong)端設備。
歷史(shi)上對電(dian)(dian)話機的改進和發(fa)明包(bao)括：碳粉話筒、電(dian)(dian)話人(ren)工交換板(ban)、撥號盤、自動電(dian)(dian)話交換機、程控電(dian)(dian)話交換機、雙音多頻撥號、語音數字采樣等。新技術包(bao)括：ISDN、DSL、模(mo)擬移動電(dian)(dian)話和數字移動電(dian)(dian)話機等。
電(dian)話電(dian)源線(xian)(xian)、電(dian)話線(xian)(xian)、收(shou)線(xian)(xian)開(kai)關、受話器(qi)、增音(yin)按鈕、送話器(qi)、本機號碼(ma)片、鈴聲及(ji)免(mian)提(ti)喇叭、記(ji)憶代碼(ma)鍵(jian)(jian)、記(ji)憶號碼(ma)片、數(shu)字按鍵(jian)(jian)、記(ji)憶取出(chu)鍵(jian)(jian)、記(ji)憶儲存鍵(jian)(jian)、重撥鍵(jian)(jian)、工作指(zhi)示燈、免(mian)提(ti)鍵(jian)(jian)、R鍵(jian)(jian)、免(mian)提(ti)送話器(qi)、鈴聲調節(jie)開(kai)關、P/T開(kai)關、免(mian)提(ti)接收(shou)音(yin)量調節(jie)旋鈕。
電(dian)話(hua)通信(xin)是(shi)通過聲能(neng)與電(dian)能(neng)相(xiang)互轉換、并利用“電(dian)”這個媒介來傳輸語言的(de)一種通信(xin)技(ji)術(shu)。兩個用戶要進(jin)行通信(xin)，最(zui)簡單的(de)形式就是(shi)將兩部電(dian)話(hua)機用一對(dui)線路連接起來。
當發話(hua)者拿(na)起電(dian)話(hua)機對著(zhu)送話(hua)器講話(hua)時(shi)，聲帶的(de)振動(dong)激勵空氣振動(dong)，形成聲波。
聲波(bo)作用于送(song)話器上(shang)，使(shi)之(zhi)產生電流(liu)，稱為話音電流(liu)。
話(hua)(hua)音電流沿著線路傳送到對方電話(hua)(hua)機的受話(hua)(hua)器(qi)內。
而受話器(qi)作用與送話器(qi)剛(gang)好相反——把(ba)電流轉化為聲(sheng)波，通過空氣傳至(zhi)人的耳朵中。
這樣，就完成了最簡單的通話過程。
電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)是(shi)美(mei)國人A.G.貝爾(er)于(yu)1876年(nian)發(fa)明的(de)(de)(de)(de)。他(ta)用(yong)(yong)兩(liang)(liang)(liang)根導線連接(jie)(jie)兩(liang)(liang)(liang)個結構(gou)完全相同、在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)磁(ci)鐵上裝有(you)(you)振(zhen)動膜片的(de)(de)(de)(de)送(song)話(hua)(hua)(hua)(hua)器和(he)受(shou)話(hua)(hua)(hua)(hua)器，首先實現(xian)兩(liang)(liang)(liang)端通(tong)(tong)(tong)話(hua)(hua)(hua)(hua)。但通(tong)(tong)(tong)話(hua)(hua)(hua)(hua)距離短、效率低。1878年(nian)出(chu)現(xian)了(le)炭(tan)精送(song)話(hua)(hua)(hua)(hua)器，使電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)送(song)話(hua)(hua)(hua)(hua)器效率大(da)大(da)提高(gao)。受(shou)話(hua)(hua)(hua)(hua)器結構(gou)也有(you)(you)改(gai)進(jin)。最早的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)是(shi)磁(ci)石電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)，靠自(zi)備(bei)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)供電(dian)(dian)(dian)(dian)(dian)(dian)，用(yong)(yong)手搖(yao)發(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)發(fa)送(song)呼叫信(xin)號。1880年(nian)出(chu)現(xian)共(gong)電(dian)(dian)(dian)(dian)(dian)(dian)式(shi)(shi)(shi)電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)，改(gai)由共(gong)電(dian)(dian)(dian)(dian)(dian)(dian)交換(huan)機(ji)(ji)(ji)(ji)集中供電(dian)(dian)(dian)(dian)(dian)(dian)，省去手播發(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)和(he)干(gan)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)。1891年(nian)出(chu)現(xian)了(le)旋轉撥(bo)號盤式(shi)(shi)(shi)自(zi)動電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)，它(ta)可(ke)以發(fa)出(chu)直(zhi)(zhi)流撥(bo)號脈沖，控制自(zi)動交換(huan)機(ji)(ji)(ji)(ji)動作，選擇被叫用(yong)(yong)戶，自(zi)動完成(cheng)交換(huan)功(gong)能(neng)。從而把電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)通(tong)(tong)(tong)信(xin)推向一(yi)(yi)個新(xin)階段。到(dao)(dao)20世(shi)紀(ji)60年(nian)代末期出(chu)現(xian)了(le)按(an)(an)鍵式(shi)(shi)(shi)全電(dian)(dian)(dian)(dian)(dian)(dian)子電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)。除(chu)脈沖發(fa)號方(fang)式(shi)(shi)(shi)外，又出(chu)現(xian)了(le)雙(shuang)音(yin)多頻（DTMF）發(fa)號方(fang)式(shi)(shi)(shi)。隨(sui)著程(cheng)控交換(huan)機(ji)(ji)(ji)(ji)的(de)(de)(de)(de)發(fa)展(zhan)，雙(shuang)音(yin)頻按(an)(an)鍵電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)已(yi)逐(zhu)步普(pu)及。電(dian)(dian)(dian)(dian)(dian)(dian)子電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)電(dian)(dian)(dian)(dian)(dian)(dian)路正(zheng)在(zai)向集成(cheng)化邁進(jin)，話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)專(zhuan)用(yong)(yong)集成(cheng)電(dian)(dian)(dian)(dian)(dian)(dian)路已(yi)廣泛用(yong)(yong)于(yu)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)電(dian)(dian)(dian)(dian)(dian)(dian)路各組成(cheng)部分。各種(zhong)多功(gong)能(neng)電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)和(he)特種(zhong)用(yong)(yong)途電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)也應運而生。到(dao)(dao)20世(shi)紀(ji)90年(nian)代初，已(yi)有(you)(you)了(le)將撥(bo)號、通(tong)(tong)(tong)話(hua)(hua)(hua)(hua)、振(zhen)鈴三種(zhong)功(gong)能(neng)集于(yu)一(yi)(yi)塊集成(cheng)電(dian)(dian)(dian)(dian)(dian)(dian)路上的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)。隨(sui)著話(hua)(hua)(hua)(hua)音(yin)識別技術的(de)(de)(de)(de)發(fa)展(zhan)，直(zhi)(zhi)接(jie)(jie)用(yong)(yong)話(hua)(hua)(hua)(hua)音(yin)“撥(bo)號”的(de)(de)(de)(de)新(xin)型電(dian)(dian)(dian)(dian)(dian)(dian)話(hua)(hua)(hua)(hua)機(ji)(ji)(ji)(ji)也正(zheng)在(zai)出(chu)現(xian)。
最初的電(dian)(dian)(dian)(dian)話(hua)(hua)機(ji)（終(zhong)端）是由微型發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)和(he)電(dian)(dian)(dian)(dian)池構成的磁石式電(dian)(dian)(dian)(dian)話(hua)(hua)機(ji)，打電(dian)(dian)(dian)(dian)話(hua)(hua)時，使用者用手(shou)搖(yao)微型發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)發(fa)(fa)(fa)出電(dian)(dian)(dian)(dian)信(xin)號呼叫(jiao)對(dui)(dui)方(fang)，對(dui)(dui)方(fang)啟機(ji)后構成通話(hua)(hua)回路。后來，1877年愛迪生(sheng)（T.E.Edison）發(fa)(fa)(fa)明(ming)了(le)(le)(le)碳素送話(hua)(hua)器和(he)誘導線路后通話(hua)(hua)距離(li)延長了(le)(le)(le)。同一年又(you)發(fa)(fa)(fa)明(ming)了(le)(le)(le)共(gong)電(dian)(dian)(dian)(dian)式電(dian)(dian)(dian)(dian)話(hua)(hua)機(ji)。1891年終(zhong)于(yu)發(fa)(fa)(fa)展到A.B.Strowger發(fa)(fa)(fa)明(ming)了(le)(le)(le)自動式電(dian)(dian)(dian)(dian)話(hua)(hua)機(ji)。
電(dian)話(hua)(hua)機(ji)設(she)置(zhi)在電(dian)話(hua)(hua)通(tong)信起點和終(zhong)點的用(yong)戶側(ce)，是電(dian)話(hua)(hua)網的用(yong)戶終(zhong)端設(she)備(bei)。現代的電(dian)話(hua)(hua)機(ji)能夠方便(bian)地實現終(zhong)端用(yong)戶之(zhi)間的呼叫和通(tong)話(hua)(hua)，是經過(guo)一百多年來許(xu)多人的研(yan)究和無數次的改(gai)進(jin)而形成的。盡管它們的式樣千(qian)差(cha)萬別，但一般都有如下基本功能：
1、聲電互換
因為要進行(xing)快速(su)的、遠距離的通信，不能直接傳送聲(sheng)音(yin)，而必須先(xian)把聲(sheng)音(yin)變(bian)成電信號（即以電作(zuo)為載(zai)體），到(dao)對方后再把電信號還原(yuan)成為聲(sheng)音(yin)。
2、摘機識別
當主(zhu)叫方(fang)拿(na)起電(dian)話機(ji)時，交(jiao)換機(ji)應有(you)能知道“有(you)人(ren)要打電(dian)話”的功(gong)能，以便交(jiao)換機(ji)做(zuo)好接續準備。
3、發送信號
自動(dong)電(dian)話機(ji)正(zheng)是通過(guo)發送撥(bo)號信號來(lai)指揮(hui)電(dian)話交換(huan)機(ji)的工作(zuo)，并進而建立兩個電(dian)話機(ji)之(zhi)間的連接的。
4、響鈴
即(ji)在對方來電(dian)話時，電(dian)話機能以鈴聲告訴主人：“有人來電(dian)話了。”
5、電接續
電話(hua)(hua)機中，實現這五(wu)大(da)功(gong)能的部件依次是：送受(shou)話(hua)(hua)器(qi)、叉(cha)簧、撥號盤(pan)（或按鍵(jian)盤(pan)）、電話(hua)(hua)鈴和(he)電話(hua)(hua)回路。
電(dian)(dian)話(hua)(hua)(hua)機(ji)(ji)具有(you)將終(zhong)端的(de)(de)音(yin)波(bo)轉換為(wei)電(dian)(dian)子信號(hao)(hao)，通過電(dian)(dian)話(hua)(hua)(hua)線(xian)傳送(song)(song)到遠距離的(de)(de)對方(fang)(fang)，同時將對方(fang)(fang)傳送(song)(song)來(lai)(lai)的(de)(de)電(dian)(dian)子信號(hao)(hao)再生為(wei)語(yu)(yu)音(yin)（音(yin)波(bo)），使其(qi)(qi)(qi)通話(hua)(hua)(hua)的(de)(de)功(gong)(gong)能，以及(ji)發(fa)送(song)(song)可從(cong)多個(ge)對方(fang)(fang)中選擇的(de)(de)信號(hao)(hao)（撥(bo)號(hao)(hao)脈沖），告知對方(fang)(fang)的(de)(de)呼叫音(yin)等功(gong)(gong)能。電(dian)(dian)話(hua)(hua)(hua)機(ji)(ji)由將語(yu)(yu)音(yin)轉換為(wei)電(dian)(dian)流發(fa)送(song)(song)到電(dian)(dian)話(hua)(hua)(hua)線(xian)的(de)(de)送(song)(song)話(hua)(hua)(hua)機(ji)(ji)、將對方(fang)(fang)傳送(song)(song)來(lai)(lai)的(de)(de)電(dian)(dian)流還原為(wei)語(yu)(yu)音(yin)的(de)(de)受(shou)話(hua)(hua)(hua)機(ji)(ji)、呼叫對方(fang)(fang)的(de)(de)撥(bo)號(hao)(hao)或(huo)按鈕、發(fa)送(song)(song)呼叫音(yin)的(de)(de)鈴聲、將這些連接在(zai)電(dian)(dian)話(hua)(hua)(hua)線(xian)上執行其(qi)(qi)(qi)功(gong)(gong)能的(de)(de)線(xian)路網等組成(cheng)。送(song)(song)話(hua)(hua)(hua)機(ji)(ji)內有(you)裝滿碳素顆(ke)(ke)粒(li)的(de)(de)小箱子，其(qi)(qi)(qi)前方(fang)(fang)有(you)薄硬鋁合金振(zhen)(zhen)(zhen)動(dong)板。振(zhen)(zhen)(zhen)動(dong)板根據語(yu)(yu)音(yin)振(zhen)(zhen)(zhen)動(dong)，振(zhen)(zhen)(zhen)動(dong)碳素顆(ke)(ke)粒(li)，碳素顆(ke)(ke)粒(li)傳導電(dian)(dian)流，隨著顆(ke)(ke)粒(li)的(de)(de)接觸程度(du)，電(dian)(dian)阻發(fa)生變(bian)化，生成(cheng)語(yu)(yu)音(yin)電(dian)(dian)流。受(shou)話(hua)(hua)(hua)機(ji)(ji)接受(shou)對方(fang)(fang)的(de)(de)語(yu)(yu)音(yin)電(dian)(dian)流后，在(zai)線(xian)圈上生成(cheng)語(yu)(yu)音(yin)電(dian)(dian)流引起的(de)(de)磁力，振(zhen)(zhen)(zhen)動(dong)鐵振(zhen)(zhen)(zhen)動(dong)板，發(fa)出聲音(yin)。
無線(xian)環路-無繩電話
電話子母機
數字無繩電話
模擬無繩電話
移動電話手機
小靈通(tong)（無線電話）
隨(sui)著IT技術的不斷的飛速發展，嵌入式(shi)終端(duan)設備的處(chu)理(li)能力(li)越(yue)來越(yue)強，21世紀初出現了(le)一種帶個人數據助理(li)（PDA）的電話機(ji)“智能電話”。
智(zhi)(zhi)(zhi)(zhi)能(neng)(neng)(neng)電(dian)話(hua)(hua)除了(le)(le)有(you)完(wan)整的(de)固定電(dian)話(hua)(hua)功(gong)能(neng)(neng)(neng)外，通常還具(ju)有(you)大(da)容量的(de)名片(pian)管理功(gong)能(neng)(neng)(neng)、來去電(dian)管理功(gong)能(neng)(neng)(neng)、防止電(dian)話(hua)(hua)騷(sao)擾（電(dian)話(hua)(hua)防火墻）功(gong)能(neng)(neng)(neng)、企業(ye)集團(tuan)電(dian)話(hua)(hua)名片(pian)（內部名片(pian)）管理功(gong)能(neng)(neng)(neng)，以(yi)及輔(fu)助辦公(gong)的(de)許多功(gong)能(neng)(neng)(neng)，比如(ru)：日(ri)程安(an)排(pai)、便箋、日(ri)歷、計算(suan)器等功(gong)能(neng)(neng)(neng)。早期的(de)智(zhi)(zhi)(zhi)(zhi)能(neng)(neng)(neng)電(dian)話(hua)(hua)通過撥號上(shang)網，具(ju)有(you)一(yi)定的(de)信(xin)息交換能(neng)(neng)(neng)力，實(shi)現了(le)(le)發(fa)(fa)送短信(xin)、接收(shou)文字(zi)信(xin)息的(de)功(gong)能(neng)(neng)(neng)。隨著固網智(zhi)(zhi)(zhi)(zhi)能(neng)(neng)(neng)電(dian)話(hua)(hua)在中國近十年的(de)發(fa)(fa)展，其(qi)處理能(neng)(neng)(neng)力加強(qiang)，逐漸(jian)地增加了(le)(le)智(zhi)(zhi)(zhi)(zhi)能(neng)(neng)(neng)手(shou)機（Smartphone）具(ju)有(you)的(de)功(gong)能(neng)(neng)(neng)。
智能(neng)電(dian)(dian)話(hua)(hua)已有(you)通過因特網上(shang)網的(de)(de)能(neng)力及較強的(de)(de)多(duo)媒的(de)(de)體功(gong)能(neng)。可以進(jin)行網絡(luo)瀏(liu)覽、音視頻的(de)(de)播放、具有(you)電(dian)(dian)子書、電(dian)(dian)子相框等(deng)功(gong)能(neng)。同時智能(neng)電(dian)(dian)話(hua)(hua)在輔(fu)助辦公、輔(fu)助營銷(xiao)、娛樂等(deng)方面的(de)(de)功(gong)能(neng)也有(you)了大(da)大(da)的(de)(de)加強。在對傳(chuan)統固定電(dian)(dian)話(hua)(hua)顛覆的(de)(de)基礎上(shang)，實(shi)現了更多(duo)的(de)(de)商務功(gong)能(neng)和PDA功(gong)能(neng)。
環境溫(wen)度：-10℃~40℃
相(xiang)對濕度：45%~95%
大氣(qi)壓(ya)力：860~1060mbar
環境(jing)噪聲：≤60dB(A)
1、工作頻(pin)率：300~3400HZ
2、脈沖通斷(duan)比：1.6±0.2∶1
3、雙音頻撥號頻偏：≤±1.5%
4、雙音(yin)頻(pin)(pin)信號電平(ping)：①低(di)頻(pin)(pin)群：-9±3dB；②高頻(pin)(pin)群：-7±3dB；③頻(pin)(pin)率組合中(zhong)高頻(pin)(pin)分(fen)量(liang)比低(di)頻(pin)(pin)分(fen)量(liang)高2±1dB
5、振鈴聲級(ji)：≥70dB(A)
6、電聲性能：
①在(zai)0公(gong)里(li)(li)時(shi)，客(ke)觀發送(song)參考當(dang)量(liang)(liang)≥+3；在(zai)3公(gong)里(li)(li)時(shi)，客(ke)觀發送(song)參考當(dang)量(liang)(liang)≤+15；在(zai)5公(gong)里(li)(li)時(shi)，客(ke)觀發送(song)參考當(dang)量(liang)(liang)≤+15。
②在(zai)0公(gong)(gong)里時(shi)(shi)，客觀(guan)接收(shou)參(can)考(kao)當(dang)量(liang)≥－5；在(zai)3公(gong)(gong)里時(shi)(shi)，客觀(guan)接收(shou)參(can)考(kao)當(dang)量(liang)≤+2；在(zai)5公(gong)(gong)里時(shi)(shi)，客觀(guan)接收(shou)摻考(kao)當(dang)量(liang)≤+2。
③在0公(gong)里時，客觀側(ce)音參(can)(can)考當量(liang)≥+3；在3公(gong)里時，客觀側(ce)音參(can)(can)考當量(liang)≥+10；在5公(gong)里時，客觀側(ce)音參(can)(can)考當量(liang)≥+10。
高科技電(dian)話機的(de)發(fa)展(zhan)都(dou)是隨著(zhu)(zhu)無線通(tong)信(xin)的(de)發(fa)達(da)而(er)形成的(de)。電(dian)話機的(de)發(fa)展(zhan)趨勢(shi)(shi)經過(guo)Digital電(dian)話機和(he)PCS后發(fa)展(zhan)到可(ke)以(yi)用(yong)衛(wei)星通(tong)信(xin)的(de)IMT-200服(fu)務。IMT-200支持信(xin)息的(de)高速傳送，Packet，畫像等多媒體的(de)服(fu)務，將來世界各(ge)個(ge)地(di)方(fang)都(dou)可(ke)以(yi)使(shi)用(yong)所有聲音(yin)電(dian)話，電(dian)報用(yong)戶直(zhi)通(tong)電(dian)路(lu)，傳呼和(he)電(dian)子郵件(jian)；隨著(zhu)(zhu)電(dian)子郵件(jian)的(de)普及，網(wang)絡也日益化，網(wang)絡電(dian)話已是不(bu)可(ke)阻擋(dang)的(de)發(fa)展(zhan)趨勢(shi)(shi)。現有的(de)固(gu)定電(dian)話，已經不(bu)能提(ti)供人們的(de)需要(yao)了。未來的(de)固(gu)定電(dian)話講(jiang)裝備攝像頭(tou)，帶有色彩的(de)液晶(jing)顯示器，我們在接(jie)固(gu)定電(dian)話的(de)時候，都(dou)能夠(gou)看到雙方(fang)。
精(jing)靈世界
】編輯上傳提(ti)供(gong)，詞(ci)條(tiao)屬于開放詞(ci)條(tiao)，當前頁(ye)面(mian)所展示(shi)的(de)詞(ci)條(tiao)介紹涉及宣傳內(nei)容屬于注(zhu)冊用戶個人編輯行為，與【電話機】的(de)所屬企業/所有人/主體無關，網站不(bu)完全保證(zheng)內(nei)容信息的(de)準(zhun)確性、真實(shi)性，也(ye)不(bu)代表本站立場，各項數據信息存在更新不(bu)及時的(de)情(qing)況，僅供(gong)參考，請(qing)以官方發布為準(zhun)。如(ru)果頁(ye)面(mian)內(nei)容與實(shi)際情(qing)況不(bu)符，可點擊“反饋”在線(xian)向(xiang)網站提(ti)出修(xiu)改，網站將(jiang)核實(shi)后進行更正。
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