1、中文 6456 字 Introduction PHS phones PHS phone is a miniature of the 1900 MHz radio transceiver call machine. Transmitting power only 10 mw, minimal radiation, the only mobile phone handset 1/200, it is green communications tool, said. 1, features , murmur of small, clear sound quality, can the city an
2、d sound quality comparable to fixed telephone, and confidentiality than fixed telephone strong. , p call can be called anytime, anywhere, and with other PHS phone calls directly. , LCD displays are a number of background light, easy to watch. , a telephone directory function, ringing sound choice, v
3、olume control, and other functions. , have a button on the redial function. , the largest PHS phones can be a feature of the home phone or office phone has a phone number, from one side of the other party can automatically cut off, to prevent eavesdropping. PHS phones can also have a virtual number,
4、 so home or office phone and PHS phones can call each other. 2, the band , 1895 MHz-1906.1MHz allocated to the private network , 1906.1 MHz-1918.1MHz distribution to the public network Each carrier frequency of 300 KHz bandwidth is available on the band frequency is 77, each district station used by
5、 the carrier frequency of: f = 1895.1 +0.36 X (N-1) MHz in the N-type for the carrier frequency, , The range is 1-77, f for the use of the air with the corresponding frequency N For example: Carrier frequency N = I f = 1895.1MHz Carrier frequency N: 2 f = 1895.46MHz Carrier frequency N = 3 f - 1895.
6、82MHz Carrier frequency N = 77 f = 1922.46MHz 3, the phone modeling , the total weight: 80 90 g (plus panels of less than 200 g) , size: two small boxes so much firewood , power supply capacity: continuous talk time of about 8 h, in a state reception for 500 h , the PHS models currently available in
7、 the market mainly UTS702-P, UTS602-A, UTS702-S331, UTS708-J, UTS708-SY, and so on. 4, Little Smart mobile phone functions PHS phones there are three main series: 1), UTS700 (popular) series of mobile phones, a low-cost mobile phones, LCD smaller, only figures show that there are four kinds of ringi
8、ng and 20 kinds of music, can store five calls have been recorded and five pulling phone records, phone book can be Store 20 phone numbers. The phone has been eliminated. 2), UTS702 (charisma) phones, mobile phones are mid-range and medium-sized LCD Chinese / English, in addition to 700 series, also
9、 a function of time, vibration, hands-free, voice recording, voice and data communications. Representative models have 702,702-331. 3), UTS708 (scenery) phones, a high-end mobile phones, large-screen LCD Chinese / English, can store 500 phone numbers, text message to support the Chinese character in
10、put. Second, the PHS mobile phone technology with the principle of indicators 1), the technical indicators PHS Transmitting power: 10 mw (average), 80 mw (peak) Frequency: 1895.150 1917.950 MHz Sensitivity: less than 16 db V ( 97 dbm) Air interface: RCR STD-28 Version 2 Carrier interval: 300 KHz Com
11、munication: TDMA / TDD Modulation: n/4QPSK Transfer rate: 384 Kbps Voice encoding: 32 K bps ADPCM Melody output: in the great volume when 73 db Tone frequency: 2800 HZ, 1800HZ Zhenchang: 5 ms 2), PHS phone calls were working principle of breath 1, PS PHS breath process , when - users to call in the
12、PS on the dial-up and sent out if all the wireless channel are already occupied, it will hear the voices, otherwise PS exhaled information put into the agreement PHS phone number, and The information transmitted to the RP. , RP PS to receive wireless link came through the information. , RP will rece
13、ive information through wired connections to the RPC (base station controllers). , RPC PHS agreement information will be converted to an agreement Q.931 information. In addition, RPC (base station controllers) from the output of information extracted dial-up code and put it into DTMF (dual-tone mult
14、i-frequency) signals, Q.931 agreement by a E1 line of the D-channel sent to the RT (infrastructure equipment ). , when RT (infrastructure equipment) to receive information breath, it translates the information to select and connect to the local exchange, the corresponding analog line interface, and
15、access to information given to the RPC. RPC path through the voice of the DTMF (dual-tone multi-frequency) dial-up signal to the Central Bureau of switches, after the completion of dial-up, RPC and RP Centre will switch between the PS and the path to link up all the voice. Called party phone ringing
16、 and pick, exhaled the end of the process, and the main call can be called mutual conversation. 2, PS people process called PHS This feature provides a PS to the basic process of incoming terminals. Through the establishment of a functional equivalent of incoming RT regional paging service area. , i
17、ncoming, the simulation of a particular line ringing. , RT-detected bell and the incoming flow of information, together with Q.931 agreement gave the call number RPC. , when the RPC received from the RT-sent to the information, it will Q.931 agreement gave the call number RPC. , these calls all the mobile phone base stations (PS) and FSU, when the pager number and the corresponding PS received from the RP of the paging information, it immediately ringing.
