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【正文】 or, a user needs the following information: Levels of Interconnects ? Level 1: chip pad to package leads, ., wire bonds ? Level 2: ponents to circuit board, ., PLCC socket ? Level 3: circuit board (boardtoboard) connector, ., edgecard for motherboard to daughter board connection ? Level 4: subassembly interconnects, ., ribbon cables ? Level 5: subassembly to I/O, ., BNC connector ? Level 6: system interconnects, ., Ether connectors Language in use ? Vocabulary – loss, shield, detrimental, degradation, ratio ? Structure ? Reading/writing techniques Vocabulary Loss in text ? Interconnect devices must meet certain performance requirements in most or all of the following categories: – Signal integrity – Power loss – … 18 ? 互連器件必須滿足下列大多數(shù)或者全部性能要求： – 信號完整性 – 功率損耗 – … Shield in text ? Electrical characteristics: contact resistance, inductance and capacitance。 voltage and power ratings。 shielding。 filtering ? 電氣特性（接觸電阻，電感和電容，電壓和功率額定值，屏蔽，濾波） Detrimental in text ? An interconnect that must pass the short rise time of a highspeed signal pulse can be detrimental to maintaining signal integrity due to an unwanted reflection. ? 因?yàn)槌霈F(xiàn)了反射，所以在通過互連路徑傳送高速信號脈沖時，短促的上升時間就會破壞信號的完整性。 Degradation in text ? Signal integrity is defined by loss of quality of the input signal. Ideally, the signal at the output of an interconnect should be equal in all characteristics with the signal at the input of the interconnect. In reality, signal degradation occurs. ? 信號完整性是指輸入信號質(zhì)量的損失。理想情況下，互連器件的輸出端信號和輸入端信號在所有特性上都完全相同。實(shí)際中會發(fā)生信號 質(zhì)量的下降。 Ratio in text ? Tests that indicate signal integrity include: – Voltage standing wave ratio (VSWR) – Frequency response – Risetime of signal edges – Current flow ? 能夠反映信號完整性的測試有： – 電壓駐波比 – 頻率響應(yīng) – 信號邊沿的上升時間 – 電流 Structure Reading / Writing techniques Unit 4 Electronic systems Lesson 10 The Mobile Telephone System (I) ? Backgrounds ? Text tour ? Language in use – Vocabulary – Structure – Reading/writing techniques 19 Backgrounds ? Terminology – cordless phone – base station, mobile station – dial tone, dialing – antenna – packetswitching – MTSO, MSC, PSTN ? The History of Mobile Radio Communication Terminology cordless phone 無繩電話 base station, mobile station ? base station ? 基站 ? mobile station ? 移動站 Dial tone , dialing A dial is… ? A graduated surface or face on which a measurement, such as speed, is indicated by a moving needle or pointer. 標(biāo)度盤 ? The face of a clock. 鐘表針盤 ? A sundial. 日晷 20 ? The panel or face on a radio or television receiver on which the frequencies or channels are indicated. 調(diào)諧度盤 ? A movable control knob or other device on a radio or television receiver used to change the frequency. 調(diào)諧鈕 ? A rotatable disk on a telephone with numbers and letters, used to signal the number to which a call is made. 電話撥號盤 Antenna ? 天線 ? A metallic apparatus for sending or receiving electromagic waves. ? also called aerial packetswitching ? 包交換，分組交換 ? A packet is … A sequence of binary digits including data and call control signals that is switched as a posite whole. The data, call control signals, and possibly error control information, are arranged in a specific format. A short block of data of fixed length and destination information. It is the unit in which information (a message) is transferred in a packetswitching work. Packets may consist of as many as 8000 bits, and more from node to node in the work. MTSO, MSC, PSTN ? MTSO: Mobile Telephone Switching Office 移動電話交換局 ? MSC: Mobile Switching Center 移動交換中心 ? PSTN: Public Switched Telephone Network 公共交換電話網(wǎng) The History of Mobile Radio Communication ? 1880: Hertz – Initial demonstration of practical radio munication ? 1897: Marconi – Radio transmission to a tugboat over an 18 mi path ? 1921: Detroit Police Department: Police car radio dispatch (2 MHz frequency band) ? 1933: FCC (Federal Communications Commission) – Authorized four channels in the 30 to 40 MHz range ? 1938: FCC – Ruled for regular service ? 1946: Bell Telephone Laboratories – 152 MHz (Simplex) ? 1956: FCC – 450 MHz (Simplex) ? 1959: Bell Telephone Laboratories – Suggested 32 MHz band for high capacity mobile radio munication ? 1964: FCC – 152 MHz (Full Duplex) ? 1964: Bell Telephone Laboratories – Active research at 800 MHz ? 1969: FCC – 450 MHz (Full Duplex) 21 ? 1974: FCC – 40 MHz bandwidth allocation in the 800 to 900 MHz range ? 1981: FCC – Release of cellular land mobile phone service in the 40 MHz bandwidth in the 800 to 900 MHz range for mercial operation ? 1981: ATamp。T and RCC (Radio Common Carrier) reach an agreement to split 40 MHz spectrum into two 20 MHz bands. Band A belongs to nonwireline operators (RCC), and Band B belongs to wireline operators (telephone panies). Each market has two operators. ? 1982: ATamp。T is divested, and seven RBOCs (Regional Bell Operating Companies) are formed to manage the cellular operations ? 1982: MFJ (Modified Final Judgment) is issued by the government DOJ. All the operators were prohibited to (1) operate longdistance business, (2) provide information services, and (3) do manufacturing business ? 1983: Ameritech system in operation in Chicago ? 1984: Most RBOC markets in operation ? 1986: FCC allocates 5 MHz in extended band ? 1987: FCC makes lottery on the small MSA and all RSA licenses ? 1988: TDMA (Time Division Multiple Access) voted as a digital cellular standard in North America ? 1992: GSM (Groupe Speciale Mobile) operable in Germany D2 system ? 1993: CDMA (Code Division Multiple Access) voted as another digital cellular standard in North America ? 1994: American TDMA operable in Seattle, Washington ? 1994: PDC (Personal Digi