CN101009780A - Digital TV mobile receiving method and multi-functional PCMCIA card based on the MAN - Google Patents

Abstract

The invention discloses a multifunctional PCMCIA card for digital TV based on a metropolitan area network and a mobile receiving method for digital TV. The PCMCIA card includes: a digital TV receiving module (1), a mobile communication module (3), and a PCMCIA interface module (2) ) and driver P; the PCMCIA interface module (2) is bidirectionally connected with the digital television receiving module (1) and the mobile communication module (3) respectively, and the PCMCIA interface module (2) comprises a PCMCIA interface control unit (21), Digital TV TS flow interface control unit (22), mobile communication interface control unit (23) and user identification card interface unit (24); Described driver program P is installed in the notebook computer (4), and described PCMCIA card and The PCMCIA port of the notebook computer (4) can be pluggably connected. The method of the present invention utilizes the existing mobile communication coverage network to carry out data return, and an ordinary notebook computer will become a digital TV mobile receiving terminal with viewing authentication, billing and video-on-demand after being inserted into the digital TV multifunctional PCMCIA card of the present invention.

Description

Digital TV mobile receiving method and multifunctional PCMCIA card based on metropolitan area network

technical field

The present invention relates to the mobile reception of digital TV and the components of the receiving terminal thereof, in particular to a terrestrial digital TV multifunction card and a mobile reception method of digital TV which combine the communication function of a mobile phone and the broadband reception function of a terrestrial digital TV, and a common notebook After the computer is inserted into the multifunctional card of the present invention, it will become a portable terrestrial digital television receiving terminal with the function of sending and receiving.

Background technique

Digital TV has flourished worldwide. China has also formulated the "Tenth Five-Year Plan" development plan, which requires that by 2005, radio and television stations above the provincial level will be digitalized, and that national radio and television will be basically networked; by 2010, national radio and television production and broadcasting will be basically realized. , digitalization of transmission, emission and reception; complete the transition from analog to digital by 2015. It is predicted that from 2004 to 2008, the scale of digital TV users in China will grow rapidly at a compound growth rate of 188.8%, and the total market size of digital TV terminals (including set-top boxes and digital TVs) in the next five years will reach 339.7 billion yuan.

At present, the transmission ways of digital TV can be divided into three types: digital satellite TV, digital cable TV and digital wireless (terrestrial) broadcast TV. Terrestrial digital TV (also known as wireless digital TV) has European standard DVB-T, American standard ATSC-T, etc. Tsinghua University has also proposed a terrestrial digital TV transmission scheme DMB-T ( Terrestrial Digital Multimedia-Television Broadcasting). Terrestrial digital TV reception is the same as cable digital TV (our country does not allow personal reception of satellite digital TV) in the following forms: (1) household digital TV receiver; (2) digital TV set-top box + household analog digital TV receiver ; (3) Digital TV receiving card + multimedia computer. Different from cable digital TV, terrestrial digital TV puts more emphasis on the mobile receiving function, so it will lead to a huge market for mobile TV receiving equipment. At present, vehicle-mounted mobile digital TVs have appeared, including automobiles, trains, subways, etc. unique territory. Mobile digital TV receivers will become emerging multimedia consumer products just like mobile phones and PDAs.

With the development of TV digitization, we already have three digital information transmission networks: radio and television network, computer network and telecommunication network. The three networks have their own characteristics and advantages, and they need complementary development to exert greater effectiveness.

At present, it is the introduction period of digital TV development, and many problems need to be solved, such as: producing TV content that attracts viewers, changing the free viewing habits of TV viewers, and establishing a digital TV charging platform, etc. Chinese TV viewers do not have the habit of paying to watch TV, and they have to rely on advertising revenue to make money when they start digital TV.

At present, we see that the mobile phone network in the telecommunication network has become the public network with the largest number of users, the widest coverage and the greatest influence. And establish a sound charging platform. my country's mobile communication network scale and number of users have ranked first in the world. A digital modern mobile communication network covering the whole country, connecting the world, advanced technology and diverse services has been basically formed, and mobile communication has become the first pillar of my country's telecommunications business. Mobile communication currently provides mobile value-added services other than voice communication services, including SMS, MMS, Internet services and other voice value-added services. The diversity of telecommunication network services has further made mobile phones a new generation of mobile information terminals after radios, televisions and computers, and a symbol of urban fashion and consumer culture. The demand for the development of mobile value-added services provides new development opportunities for related industries.

Both the mobile digital TV receiving card and the mobile phone have the ability to receive and process information on the move. The design foundations of the two have many commonalities, and they also have their own advantages. Mobile digital TV has high picture and sound playback quality and sufficient TV spectrum resources; mobile phones are easy to operate and are familiar to many users, and the operation of mobile communication networks is also very mature. As people's demand for massive amounts of information anytime and anywhere is getting stronger and stronger, the combination of the two will definitely continue to give full play to the potential of mobile communication networks and promote the development of terrestrial digital TV.

Now there is the concept of watching TV on mobile phones, but the current domestic TV programs on mobile phones are based on a separate mobile communication system GPRS or CDMA 1x data channel, and transmit TV programs to an on-demand user in the form of IP streaming media. The data compression format is often the way of high compression rate MPEG4. In this way, even in the 3G era, the data rate has evolved compared to the 2G network, but there are still inherent defects in the transmission of video broadcasting programs, such as low-quality images, expensive use and construction costs, etc. Tsinghua University proposed and successfully developed the terrestrial digital multimedia television broadcasting transmission scheme DMB-T (Terrestrial Digital Multimedia-Television Broadcasting) and the time-domain synchronous orthogonal frequency division multiplexing multi-carrier modulation technology TDS-OFDM (TimeDomain Synchronous Orthogonal Frequency Division Multiplex) , with relatively complete independent intellectual property rights. The Ministry of Information Industry and the State Administration of Radio and Television have formally notified the program to the International Telecommunication Union (ITU). DMB-T is the only domestic transmission scheme with an industrial basis, which makes the European standard technically unable to be adopted by our country as a national standard. Shenzhen Tsinghua Research Institute, as the promotion base for the industrialization of Tsinghua University's DMB-T standard terrestrial digital TV, combined mobile digital TV receivers with mobile communication handsets in the process of developing portable digital TV terminals relying on independent TV standards, and proposed for the first time based on The development idea of terrestrial digital TV receiving PCMCIA card with mobile backhaul function in metropolitan area network.

Contents of the invention

The technical problem to be solved in the present invention is to design a kind of terrestrial digital TV that can utilize existing mobile communication coverage network, such as GPRS or CDMA 1x data channel to carry out data return, and utilize notebook computer to broadcast the needs of terrestrial digital TV. Receiving card and mobile receiving method of digital TV.

The technical solution adopted by the present invention to solve technical problems is as follows: design a kind of digital TV multifunctional PCMCIA card based on metropolitan area network, comprising:

Digital TV receiving module, the digital TV receiving module has a special antenna for terrestrial digital TV, used to receive and process the radio frequency signal of terrestrial digital TV, and output TS code stream;

Mobile communication module, the mobile communication module has a special antenna for mobile phone, which is used to realize the user's return channel, and realize the viewing authentication, billing and video on demand of digital TV;

As the PCMCIA interface module of communication interface and driver program P thereof, described PCMCIA interface module is connected with digital TV receiving module and mobile communication module two-way respectively, and the signal output end of described PCMCIA interface module is connected notebook computer, and described driver program P is connected installed in the laptop.

Described PCMCIA interface module comprises PCMCIA interface control unit and the digital television TS flow interface control unit, mobile communication interface control unit and user identification card interface unit that are bidirectionally connected with PCMCIA interface control unit respectively, and described PCMCIA interface control unit passes PCMCIA plug Pluggable connection with the PCMCIA port of the notebook computer. The user identification card interface control unit unit, the digital TV TS code stream interface control unit unit and the mobile communication module interface control unit unit are independent of each other, and all data enters the notebook computer through the notebook computer PCMCIA interface control unit for processing. Thus, an ordinary notebook computer with PCMCIA interface and Windows 2000 or above operating system immediately becomes a portable terrestrial digital TV receiving terminal with transceiver function.

The digital TV receiving module includes a radio frequency tuner, a channel decoder and a PID filter based on FPGA; the radio frequency tuner receives the TV radio frequency signal induced by the special antenna for terrestrial digital TV, and amplifies and tunes the TV radio frequency signal to output the intermediate frequency (IF) signal passes to channel decoder and carries out demodulation process, and the intermediate frequency signal after the demodulation is sent into described PID filter based on FPGA and filters, and described PID filter based on FPGA is to described PCMCIA interface by 12C bus The module's digital TV TS stream interface control unit outputs TS code stream.

The mobile communication module includes a sending radio frequency unit, a receiving radio frequency unit and a baseband signal processing circuit; the sending radio frequency unit modulates the data stream signal output by the baseband signal processing circuit into a radio frequency signal, which is emitted by the antenna; The receiving radio frequency unit amplifies, demodulates, and digitizes the signal received by the antenna with low noise, recovers the digital baseband signal and sends it to the baseband signal processing circuit, and the baseband signal processing circuit is bidirectionally connected with the mobile communication interface control unit of the PCMCIA interface module .

The driver P has a layered structure, including: the lowest operating system core layer, a hardware driver layer above the bottom layer, and the hardware driver layer includes a digital TV hardware driver layer, a system hardware driver layer and a mobile communication layer. Hardware interface software layer; the application layer above the hardware driver layer, the application layer includes TS transport stream data management, data service and application protocol software, mobile communication network layer and mobile communication data link layer, and the uppermost man-machine interface layer, that is, user control, graphic display/screen display, program control and authorization information management. The above-mentioned driver P is recorded on a CD, and the driver P is installed on the notebook computer using the digital TV multifunctional PCMCIA card of the present invention for the first time.

The technical solution adopted by the present invention to solve technical problems also includes: a mobile digital TV receiving method based on a metropolitan area network, characterized in that: the hardware environment of the method is to insert the aforementioned multifunctional PCMCIA card on a notebook computer, and its software Environment is that the driver software P of this PCMCIA card is installed in described notebook computer, and this method comprises the steps:

a. The RF tuner in the PCMCIA card receives the TV RF signal induced by the special antenna for terrestrial digital TV, amplifies and tunes the TV RF signal, and then outputs the intermediate frequency (IF) signal to the channel decoder;

B. channel decoder carries out demodulation processing to described intermediate frequency (IF) signal, and the IF signal after demodulation becomes the TS bit stream that comprises video program, audio program and data program after the filter processing of the PID filter based on FPGA;

c. the notebook computer receives the TS code stream output by the FPGA-based PID filter through the PCMCIA interface module and stores the TS code stream in the program storage area;

d. The notebook computer (4) invokes the driver software P of the PCMCIA card to read the TS code stream data and utilizes the display screen of the notebook computer to play digital TV programs.

The digital TV mobile receiving method utilizes the existing mobile communication coverage network to carry out data return, and realizes viewing authentication, billing and video-on-demand of digital TV. Contains two processes:

Process 1: the transmitting radio frequency unit modulates the data stream signal output by the baseband signal processing circuit into a radio frequency signal, which is transmitted by the antenna;

Process 2: The receiving radio frequency unit amplifies, demodulates, and digitizes the signal received by the antenna with low noise, recovers the digital baseband signal and sends it to the baseband signal processing circuit for processing, and finally sends it to the notebook as the viewing terminal through the PCMCIA interface module (2) computer.

Compared with the prior art, the present invention has the following advantages based on the digital TV multifunctional PCMCIA card of the metropolitan area network and the digital TV mobile receiving method:

1. Combining digital TV broadcasting and mobile communication network, that is, receiving digital TV programs through the terrestrial digital TV broadcasting network, using the mobile communication network to realize the user's return channel, and realizing digital TV viewing authentication, billing and video on demand;

2. The digital TV receiving terminal combined with digital TV multi-function card and notebook computer has portable mobility, so it has advantages in mobile video conferencing, mobile web browsing, and mobile file download;

3. It has broadcast-style free-to-air TV reception, and there is no peak usage effect when broadcasting;

4. Due to the powerful functions of the notebook computer, digital TV programs can be downloaded, stored and played back at any time;

5. It can be applied to network TV games.

Description of drawings

The descriptions of the attached drawings are as follows:

Fig. 1 is the composition schematic diagram of the digital TV multifunctional PCMCIA card based on the metropolitan area network of the present invention;

Fig. 2 is the principle block diagram of digital TV receiving module 1 among Fig. 1;

Fig. 3 is a schematic block diagram of the mobile communication module 3 in Fig. 1;

Fig. 4 is the principle block diagram of PCMCIA interface module 2 among Fig. 1;

FIG. 5 is a schematic diagram of the layered structure of the driver program P. As shown in FIG.

Detailed ways

The device of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, the digital TV multifunctional PCMCIA card based on the metropolitan area network of the present invention comprises: digital TV receiving module 1, PCMCIA interface module 2, mobile communication module with mobile phone special antenna 5 with terrestrial digital TV special antenna 3 and laptop 4. The PCMCIA interface module 2 is bidirectionally connected with the digital TV receiving module 1 and the mobile communication module 3 respectively, and the notebook computer 4 is connected to the signal output end of the PCMCIA interface module 2 .

Described digital TV receiving module 1 comprises radio frequency tuner 11, channel decoder 12 and the PID filter 13 based on FPGA; Described radio frequency tuner 11 receives the TV radio frequency signal that terrestrial digital TV special antenna 5 induces, and this TV radio frequency The signal is amplified, tuned and processed and the output intermediate frequency (IF) signal is passed to the channel decoder 12 for demodulation processing, and the PID filter 13 based on the FPGA is sent to the digital TV TS stream interface control unit of the PCMCIA interface module 2 by the 12C bus 22 outputs the TS code stream, as shown in FIG. 2 . The radio frequency tuner 11 is a silicon chip type, and the TUA6034 tuner IC of Infineon can be used. And the channel decoder 12 needs to carry out different demodulation processes respectively according to different terrestrial digital standards: as ATSC-T is carried out the demodulation of vestigial sideband modulation (VSB); Carry out coded orthogonal frequency division modulation (COFDM) to DVB-T ) demodulation process, and perform time domain synchronous orthogonal frequency division multiplexing multi-carrier modulation (TDS-OFDM) demodulation on DMB-T. The channel decoding circuit of DBM-T is currently mainly composed of the channel decoding chip LGS-8222-A1 of Tsinghua University. The PID filter 13 based on FPGA can filter 32 channels of PID at the same time, and can also distinguish the TS code stream of MPEG2 and IP packets, and output the filtered TS code stream to the PCMCIA interface module. There are many solutions implemented by FPGA, such as the EPIC3T100 chip of ALTERA Company.

As shown in Figure 3, the mobile communication module 3 includes a sending radio frequency unit 31, a receiving radio frequency unit 32 and a baseband signal processing circuit 33, and the sending radio frequency unit 31 converts the data stream outputted by the baseband signal processing circuit 33 The signal is modulated into a radio frequency signal (such as 800MHz, 900MHz or 1800MHz), which is emitted by the antenna 6; the receiving radio frequency unit 32 amplifies, demodulates, and digitizes the signal received by the antenna 6 with low noise, recovers the digital baseband signal and sends it to A baseband signal processing circuit 33 , the baseband signal processing circuit 33 is bidirectionally connected with the PCMCIA interface module 2 . The baseband signal processing circuit 33 is mainly composed of a system silicon chip (System on chip) baseband chip, which is different according to the technical standards adopted, such as GSM2 generation, 2.5 generation and 3 generation technology and CDMA2 generation, 2.5 generation and 3 generation Generation, the baseband chip system will have different options. Many companies can supply complete sets of chipsets in large quantities, such as TI, ADI/TTP, Lucent, VLSI, etc. The baseband signal circuit 33 includes processing functions such as channel encoding/decoding, encryption/decryption, channel separation, reference clock circuit, and code rate adapter.

The PCMCIA interface module 2 includes a notebook computer PCMCIA interface control unit 21 , a user identification card interface control unit 24 , a digital TV TS stream interface control unit 22 and a mobile communication module interface control unit 23 . The PCMCIA interface control unit 21 is bidirectionally connected with the user identification card interface control unit 24, the digital TV TS stream interface control unit 22 and the mobile communication module interface control unit 23 respectively, and the user identification card interface control unit 24 , digital TV TS stream interface control unit 22 and mobile communication module interface control unit 23 are independent of each other, and all data enters the notebook computer through the PCMCIA interface control unit 21 of the notebook computer for processing, as shown in Figure 4 . The four parts of the whole PCMCIA interface module 2 can be realized with a piece of FPGA of ALTERA Company, and can also be realized with respective respective chips, such as the SAA7135 chip of PHILIP Company for the PCMCIA interface control unit 21 and the digital TV TS stream interface control unit 22 Realize, while the mobile communication module interface control unit 32 and the user identification interface control 24 can be realized through GPIO port programming. The user identification card interface unit 24 is aimed at different standards, namely a SIM interface (suitable for GSM) and a UIM interface (suitable for CDMA).

Described notebook computer 21 is equipped with driver program P, the operating system of Windows 2000 above version, is equipped with PCMCIA interface.

FIG. 5 is a schematic diagram of the layered structure of the driver program P. As shown in FIG. The driver program P has a layered structure, including: the lowest operating system core layer, and various processes/equipment/memory management functions provided by the embedded operating system, etc. are all realized on this level; It is an operating system of Windows 2000 or above. The hardware driver layer above the bottom layer, it completes the interface drive to the external hardware. Such as digital TV hardware driver layer, system hardware driver layer and mobile communication hardware interface software layer;

The application layer above the hardware driver layer, such as TS transport stream data management, program control, authorization information management, data service and application protocol software, mobile communication network layer and mobile communication data link layer, this layer can call the hardware driver layer, Implement data management and application protocols;

The top layer is the man-machine interface layer, such as user control, frequency tuning, program downloading, etc.

The mobile receiving method of the digital television of applying multifunctional PCMCIA card of the present invention and driver program P thereof is as follows:

The radio frequency tuner 11 in the PCMCIA card receives the television radio frequency signal that ground digital television special-purpose antenna 5 induces, and this television radio frequency signal is amplified, after the tuning process, output intermediate frequency (IF) signal to channel decoder 12;

b. Channel decoder 12 carries out demodulation processing to described intermediate frequency (IF) signal, and the IF signal after demodulation becomes the TS code that comprises video program, audio program and data program after the filter processing of PID filter 13 based on FPGA flow;

c. the notebook computer 4 receives the TS code stream based on the FPGA-based PID filter 13 output by the PCMCIA interface module 2 and stores the TS code stream in the program storage area;

d. The notebook computer 4 calls the driver software P of the PCMCIA card to read the TS code stream data and uses the display screen of the notebook computer 4 to play digital TV programs.

The digital TV mobile receiving method utilizes the existing mobile communication coverage network to carry out data return, and realizes viewing authentication, billing and video-on-demand of digital TV. Contains two processes:

Process 1: the transmitting radio frequency unit 31 modulates the data stream signal output by the baseband signal processing circuit 33 into a radio frequency signal, which is transmitted by the antenna 6;

Process 2: the receiving radio frequency unit 32 amplifies, demodulates, and digitizes the signal received by the antenna 6 with low noise, recovers the digital baseband signal and sends it to the baseband signal processing circuit 33 for processing, and finally sends it to the terminal as a viewing terminal through the PCMCIA interface module 2 laptop4.

Claims (9)

1, a kind of Digital Television multi-functional PCMCIA card based on metropolitan area network comprises:

Digital TV receiver module (1), this digital TV receiver module (1) has terrestrial DTV dedicated antenna (5), is used to receive and handle the radiofrequency signal of terrestrial DTV, and output TS code stream;

Mobile communication module (3), this mobile communication module (3) has mobile phone dedicated antenna (6), is used to realize user's return path, realizes rating authentication, charging and the video request program of Digital Television; It is characterized in that:

Also comprise pcmcia interface module (2) and driver P thereof as communication interface, described pcmcia interface module (2) respectively with digital TV receiver module (1) and two-way connection of mobile communication module (3), the signal output part of described pcmcia interface module (2) connects notebook computer (4), and described driver P is installed in the notebook computer (4).

2, the Digital Television multi-functional PCMCIA card based on metropolitan area network according to claim 1, it is characterized in that: described pcmcia interface module (2) comprises pcmcia interface control unit (21), with the two-way digital TV TS stream interface control unit (22) that is connected of pcmcia interface control unit (21), mobile communication interface control unit (23) and subscriber identification card interface unit (24), described pcmcia interface control unit (21) can plug with the PCMCIA mouth of notebook computer (4) by the PCMCIA plug and be connected respectively.

3, the Digital Television multi-functional PCMCIA card based on metropolitan area network according to claim 2 is characterized in that: described digital TV receiver module (1) comprises radio-frequency tuner (11), channel decoder (12) and based on the pid filter (13) of FPGA; Described radio-frequency tuner (11) receives the TV RF signals that terrestrial DTV dedicated antenna (5) induction comes, to this TV RF signals amplify, tuning processing output intermediate frequency (IF) signal passes to channel decoder (12) and carries out demodulation process, intermediate-freuqncy signal after the demodulation is admitted to described pid filter based on FPGA (13) and carries out filtering, and described pid filter based on FPGA (13) is exported the TS code stream by the 12C bus to the digital TV TS stream interface control unit (22) of described pcmcia interface module (2).

4, the Digital Television multi-functional PCMCIA card based on metropolitan area network according to claim 2 is characterized in that: described mobile communication module (3) comprises the radio frequency unit of posting a letter (31), collection of letters radio frequency unit (32) and base band signal process circuit (33); The described radio frequency unit of posting a letter (31) is modulated to radiofrequency signal with the traffic spike of described base band signal process circuit (33) output, is launched by antenna (6); The amplification of signal low noise, demodulation, signal digitalized that described collection of letters radio frequency unit (32) receives antenna (6), recover digital baseband signal and deliver to base band signal process circuit (33), the two-way connection of mobile communication interface control unit (23) of described base band signal process circuit (33) and pcmcia interface module (2).

5, according to claim 1,2,3 or 4 described Digital Television multi-functional PCMCIA cards based on metropolitan area network, it is characterized in that: described driver P has the structural system of layering, comprise: the operating system kernel layer of the bottom, hardware driving layer on bottom, described hardware driving layer comprise Digital Television hardware driving layer, system hardware Drive Layer and mobile communication hardware interface software layer; Application layer on the hardware driving layer, this application layer comprises the management of TS transmit flow data, the human-machine interface layer of data, services and application protocol software, mobile communications network layer and the mobile data link layer and the superiors, i.e. user's control, picture and text demonstration/screen display, program control and authorization message management.

6, according to claim 1,2,3 or 4 described Digital Television multi-functional PCMCIA cards, it is characterized in that: must possess the operating system of pcmcia interface and Windows 2000 above versions with the described notebook computer (4) that is connected based on the Digital Television multi-functional PCMCIA card of metropolitan area network based on metropolitan area network.

7, a kind of digital TV mobile receiving method based on metropolitan area network, it is characterized in that: the hardware environment of this method is to go up at notebook computer (4) to insert multi-functional PCMCIA card as claimed in claim 1, its software environment is that the drive software P of this pcmcia card is installed at described notebook computer (4), and this method comprises the steps:

A. the radio-frequency tuner (11) in the described pcmcia card receives the Digital Television radiofrequency signal that terrestrial DTV dedicated antenna (5) induction comes, to this Digital Television radiofrequency signal amplify, tuning processings back output intermediate frequency (IF) signal is to channel decoder (12);

B. channel decoder (12) carries out demodulation process to described intermediate frequency (IF) signal, and the intermediate-freuqncy signal after the demodulation becomes the TS code stream that comprises video frequency program, audio program and data programs through after pid filter (13) Filtering Processing based on FPGA;

C. described notebook computer (4) receives the TS code stream of described pid filter based on FPGA (13) output and this TS code stream is left in program storage area by described pcmcia interface module (2);

D. the drive software P that described notebook computer (4) calls pcmcia card reads the TS bit stream data and utilizes the display screen of notebook computer (4) to play digital television program.

8, the digital TV mobile receiving method based on metropolitan area network according to claim 7, it is characterized in that: the existing mobile communication overlay network of described digital TV mobile receiving method utilization carries out the data passback, realizes rating authentication, charging and the video request program of Digital Television.

9, the digital TV mobile receiving method based on metropolitan area network according to claim 8 is characterized in that: the existing mobile communication overlay network of described utilization carries out the data passback and comprises two processes:

Process one: the radio frequency unit of posting a letter (31) is modulated to radiofrequency signal with the traffic spike of described base band signal process circuit (33) output, is launched by antenna (6);

Process two: the amplification of signal low noise, demodulation, signal digitalized that collection of letters radio frequency unit (32) receives antenna (6), recover digital baseband signal and deliver to base band signal process circuit (33) and handle, pass through pcmcia interface module (2) at last and be sent to notebook computer (4) as the rating terminal.

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