TW200427299A - Circuitry to establish a wireless communication link - Google Patents

Abstract

An apparatus transmits an Internet data signal over a wireless communication link. The apparatus includes a base unit having a wired connection to a telephone line. The base unit transmits data to and from the telephone line via the wired connection. The apparatus also includes a remote unit having a wired connection to a modem. The remote unit transmits data to and from the modem via the wired connection. The remote unit and the base unit communicate with each other over the wireless communication link. The base unit includes a radio frequency transmitter to transmit the data signal to the remote unit and an automatic gain control circuit that keeps a peak amplitude of the data signal substantially constant and within a linear amplification range of the radio frequency transmitter.

Description

200427299 发明 Description of the invention (The description of the invention should state: the technical field to which the invention belongs, the prior art, the content, the embodiments and the brief description of the illustrations) I. The technical field to which the invention belongs This invention relates to the wireless connection between modems and telephone lines Tong Zuo System 0 2. The computers connected to modems in the prior art are often connected to the Internet via a wired connection. Take wired connection for Internet access as an example, a one-core telephone line is connected to the personal computer (pc) and the telephone socket on the wall. In the socket, this two-core telephone line is connected to a twisted-pair telephone line from the telephone company's central office (referred to as, regional loopback). There are many restrictions on the use of wired connections, such as the ^ # line connection. The portability of the computer will be limited, because it depends on whether there is a telephone line socket nearby. Therefore, the development of wireless links can reduce people's demand for wired links. Some of the products on the market use electronic motors Engineering Society (IEEE) 8 02.1 lb. For example, A ir ρ rt of Apple Computer, which is popular among users, includes a base station and at least one line circuit card to be fixed in a portable computer. The IEEE standard has a data transmission capacity of up to 11 million bits per second, and can handle many users in the Ethernet local network while surfing the Internet. Its use is based on the ISM (Industrial, Industrial, Scintific, Medical (Industrial, Scientific, Medical) radio frequency bands, and use frequency hopping spread spectrum (Freqeuncy Hopping Spread Spectrum? FHSS) or direct sequence 歹 J spread spectrum (Direct Sequnce Spread Spectr um 'DSSS) digital modulation format. 6 200427299 Because of this system, it has a considerable amount of data transmission capacity, which can be used to transmit the signal of I line or digital subscriber line (DSL) machine, and serve as a network computer. Airport base The station also has a dial-up (diai_up) modem, which can be connected to a circuit jack (jack). The data stream with% kilobits per private (Kbit / S) and additional control signals are converted into 8 0 2 · 1 1 b format, and wireless transmission to a laptop computer (laptop computer). The above is a more expensive method. Other types of wireless modems use short-range RF paths from the phone end Connected to a portable computer to transmit dial-up modem signals. These modems use an analog / digital converter to digitize the input v · 3 4 or V. 90 signals and use four-quadrant amplitude modulation on the RF channel.

(Quadrature Phase Shitf Keying, QPSK) or FSK to send digital data streams. Since the V · 90 signal must be transmitted very accurately, the transmitting end needs a high-bit (e.g., 1 0-1 12-bit) analog / digital converter and the receiving end needs a high-bit digital / analog converter. The above configuration results in a high-bit-rate transmission rate using the RF channel, which requires an RF bandwidth of approximately 200 kilohertz (KHz). The above-mentioned bandwidth is much larger than the 30 Hz of the analog frequency modulation (FM) radiotelephone and the 100 Hz required by some digital radiotelephones. Excessive bandwidth requirements will make modems with these configurations unattractive. The distance from Internet users to the telephone company's central office network service provider1 (Internet Service Provider (ISP) equipment varies, and can range from hundreds of feet to miles. This makes it difficult to accurately match the phone interface, and sometimes it can cause a physical echo in the system. Most, "wired" modems are equipped with modem echo cancellers to eliminate most of the echoes. In wireless systems, sometimes the echo is stronger than the data signal and saturates the radio channel. Saturated or excessive The driving circuit will cause the data signal to be linearly distorted and make the modem's echo canceller ineffective. Prior to this, the echo canceller was included in the base of the wireless modem, eliminating the echo before the RF channel was full. The noise canceller is digital, and the solution is to turn the signal to digital and then back to analog. Analog / digital and digital / analog conversion will obviously cause additional complexity to the data channel. Unless Using very horse bit conversion, V.90 will reduce the speed to V.34. The above-mentioned change in distance < results in a change in the signal level of the dial-up modem by 30 d Β. Since the modem can handle the above This is not a problem in wired mode operation. However, in wireless systems, signal level changes will be a problem. At the input of the FSK radio frequency channel, if the signal decreases 30dB, which reduces FM frequency modulation. This 30 dB not only reduces the signal-to-noise ratio and makes the system inoperable. The solution is to introduce an automatic gain controller (Automatic GainControl, AGC) or automatic level control (Automatic Level Control, ALC) unit to ensure the input level. However, when a new modem starts to communicate, it sends out tones of different levels to perform a handshake procedure to correct the signal level to The number of distance variables. An AGC / ALC circuit will cancel the above-mentioned handshake process and cause system instability. III. Summary of the Invention 200427299 Generally speaking, according to a feature of the present invention, the present invention is a dial-up modem through wireless communication A circuit system connected to transmit data signals. Data # such as V · 3 4 signal has a complex multi-level vertical amplitude modulation (QAM) modulation symbol set (constellation) and is similar to a 4KHz telephone channel The analog fundamental frequency signal is transmitted. Another example is the signal of V. 9 0. The V · 9 0 signal is a bit special, which includes 1 2 8 layers Amplitude-level Pulse Amplitude Modulation (PAM) signal 'and it is spaced according to the U-Law expander of the telephone network of the Digital Public Switched Telephone Network 5 PSTN (Space) is different. In order to accurately transmit these signals, we need low-noise and high-amplitude linear characterization channels. An effective method for transmitting these signals in RF channels is to directly link the RF carrier with V.34 or V. 90 signal for FM frequency modulation. As far as V · 90 is concerned, it is necessary to transmit a FrequenCy Shift Keying ′ FSK signal with discrete levels of 128 different intervals. The proper RF bandwidth required to transmit this signal is 30 kHz, which is the same as the analog FM channel used by traditional wireless telephones. Of course, if you increase the FM bandwidth, the signal-to-noise ratio will be improved. This circuit system includes a novel automatic gain control circuit 'which receives a data signal and substantially maintains the data signal at a fixed peak amplitude and within a preset linear amplification range. This circuit system also includes a transmitter with a preset linear amplification factor, which receives an analog signal from an automatic gain control circuit and modulates 200427299 to produce a radio frequency (RF) carrier. This feature may also include one or more of the following features. This circuit system contains a composite circuit that isolates the input signal from the output signal in the telephone line. The output signal voltage of this composite circuit may exceed the linear amplification range of the transmitter. We use an automatic gain control circuit (AGC) to limit the signal voltage, which can reduce or limit non-linear distortion in the transmitter. The AGC also prevents the signal level from appearing too low in the radio channel. The low signal level is due to the long distance (also known as the long circuit) between the consumer and the telephone office. This circuit system can also include a duplexer, which keeps the separated state between the transmitted and received RF signals. The transmitter may be a radio frequency (RF) transmitter, which includes a frequency modulator (FM), which modulates a radio frequency carrier with the frequency of the data signal. The automatic gain control circuit adjusts the signal voltage of the signal before the signal is input to the frequency modulator. The circuitry of the near-end unit (i.e., the base) may include a microprocessor whose control signals are transmitted to the far-end wireless unit. The remote wireless unit communicates with the near-end unit via a wireless communication link. Another feature of the present invention is to provide an analog signal wireless communication link. The device includes a near-end unit wired to a telephone line. The near-end unit transmits data over a telephone line via a wired connection. The device also includes a remote unit (wireless) connected to the modem. The remote unit is connected to the modem via wire to transmit data between the two. The remote wireless unit and the near-end unit communicate with each other via a wireless link. The near-end unit includes a radio frequency transmitter to send wireless data signals to the remote radio unit 10 200427299 yuan, and an automatic gain control circuit to substantially maintain the data signal at a fixed peak amplitude and maintain the radio frequency transmitter Within the preset linear magnification range. This feature may also include one or more of the following features. The near-end unit includes a radio frequency receiver and a composite circuit. The radio frequency receiver can receive the data transmitted by the far-end wireless unit and transmit it to the central office of the telephone (output signal or upload signal). The input signal in the line or the signal for downloading the data stream is separated from the output signal. Because of the unbalanced impedance, when the analog signal of the input passes through the composite circuit, it may contain a large number of output signals. At this time, the automatic gain control circuit will maintain the synthesized signal at a fixed peak voltage. This level is sufficient to reduce the non-linear distortion and in the radio channel, the signal-to-noise ratio can be sufficiently high. The remote wireless unit may also include a composite circuit that separates the input signal from the output signal in the telephone line. The automatic gain control circuit can adjust the uploaded signal level to obtain a better level of non-linear noise, so that the radio has a higher signal-to-noise ratio. The aforementioned devices can also be used to operate like radiotelephones. In this case, the near-end unit can be a radiotelephone near-end unit, and the far-end radio unit can be a radiotelephone microphone (near-end unit). And the remote wireless unit may include a speaker, a microphone, and a dial. The invention in this way is a dual-function radiotelephone, which can be connected to the Internet for normal voice communication or data signal transmission. Another feature of the present invention is to provide a device for transmitting data over a wireless communication link. The device includes: a device that generates an analog signal 11 200427299; a device that reduces the non-linear distortion of the data signal when connected through wireless communication. Other features and advantages of the present invention will be apparent from the following description, including the claimed patent scope and illustrations. 4. Embodiment The present invention is a circuit system for dialing a modem to transmit analog signals through a wireless communication link. The data signal (for example, V. 3 2 or V · 34 signal) has a complex multi-order vertical amplitude modulation (QAM) modulation symbol set (constellation) and is transmitted by a 4KHz telephone channel analogy Fundamental frequency signal. Another example of data signals is the signal transmitted by V. 90. The V. 90 signal is a bit special. It includes a 128-layer Pulse Amplitude Modulation (PAM) signal, and it is based on the telephone network of the Public Switched Telephone Network (PSTN). The audio (ϋ-Law) expander has a different space. In order to accurately transmit the signal of the dial-up modem, a low-noise and high-amplitude linear characteristic channel is required. According to the present invention, an effective method for transmitting these signals in the radio frequency channel is to directly tune the RF carrier wave with the V.34 or V.90 signal. As for the ν · 90 signal, it is necessary to transmit a total of Frequency Sin ft Keying (FSK) signals with 128 different intervals. The proper radio frequency bandwidth required to transmit this signal is 30 KHz, which is similar to the bandwidth of an analog FM channel used in traditional radiotelephones. 12 200427299 The present invention is described as a system for establishing a communication link between a dial-up fork, a power bank, and a power bank between dial-up data lines. Needs to be connected without affecting the Internet. Dry & deep dial-up network connection standards fall, for example, the road can be based on the latest dial-up bit rate (kb / s) data transmission speed. The mother heart reaches according to the standard helmet lightning% > p i i uses _ p to operate, the circuit system described here is the rate modulation (FM / FSK) architecture, instead of a few meters. Transmit v.90silv.92 data message in traditional audio channel. The data transmitted by ^ s channel is compared to audio data. The dagger-circuit system therefore avoids the use of analog / digital and digital / analog conversion actions that may reduce the performance of v.90 or v 92, and the same: avoids the higher bandwidth required for digital RF modulation. A standard digital telephone line can also be used to transmit dial-in data signals. But speed will be reduced by analog / digital conversion. In the above-mentioned circuit system, a novel and low-cost automatic pong control (AGC) circuit is used to eliminate the non-linear distortion of the RF circuit caused by the echo of the telephone line. At the same time, the AGc circuit can maintain the level of data Ub to achieve the signals required by the radio frequency channel. The wireless connection established by the circuit system described in the present invention is established using the following two components: the base (heart " Rem () te unit). These components have the following setting methods. A heart cord connects the modem of the computer to the remote wireless unit, which is powered by the battery (or via The computer's USB or pc card is powered by 13 200427299 line to provide power) The remote wireless unit operated can be placed in a small box with an antenna. The two-core phone line can carry both input and output directions. Data signals include uploading from a modem and downloading to a modem for full-duplex operation. The data signal of the modem can be V. 90 type, which is composed of a 128-level baseband signal. The 4kHz spectrum width can be transmitted in the traditional audio channel. The remote wireless unit includes a radio frequency transmitter and receiver, which can operate in the radio frequency band of a 900MHz or 2.4.1 ^ radiotelephone to carry back and forth. According to the machine signal. The transmission on the wireless channel is "four-core", which is different from the two-core telephone line transmission. The wireless transmission can be started by frequency modulation (FM). The FM channel can meet the requirements of V. 9 The urgent linear requirement of the 0-type transmission signal. The remote wireless unit communicates with the base connected to the wall socket through a wireless connection. The remote wireless unit uses a slightly different carrier frequency for two-way communication. Transmission. The base includes dual RF transmitters and receivers. In addition, the circuit system between the wall socket and the telephone line needs to transmit and receive dual audio V. 90 signals (duplex). The base contains a limited transmission to A circuit system for the non-linear distortion of the signal of the modem. This circuit system uses AGC circuit to limit the peak amplitude, which can be transmitted on the FM radio frequency channel, and keep the distortion within the rigorous requirements of the V. 9 0 system. With the automatic gain control circuit in the base, the wireless link can be made substantially linear, so for the V.90 signal transmitted, this wireless link is It doesn't come out. This means that the function of canceling the echo on the telephone line 14 200427299 can be performed with a standard wireless echo canceler (and built in the computer modem). The circuit that establishes the wireless link Department,

^ In addition to the base AGC and additional circuit systems, as well as the following components of the remote helmet μ sand 无线 wireless unit, using the existing FM technology and the like ^ ^ _ than the chip set developed by the wireless phone. This circuit system provides a perfect connection with the computer's packet modem, without any modification to the hardware and software in the modem (such as communication protocols, etc.). The remote wireless unit can be battery operated and charged in a base. Operate according to a standard radiotelephone to reset the secuHty (R) code. The computer's USB cable can also be used to provide operating power. In this column, a fixed security code can be used and stored in the electronic erasable programmable read-only memory (EEpROM 56) of the remote wireless unit. There are 60 channels in the 900MHz frequency. The RF channel selection can be automatic or through the button of the remote wireless unit. Figure 1 shows a wireless communication system. The wireless communication system i 〇 includes a base 11 and a remote wireless unit 丨 2. The components of these two units are the same as or similar to those shown in the standard 900 MHz wireless telephone circuit. · The back-end wireless unit 12 and the computer 13 have an interface connection, so that the computer 13 can transmit / receive data on the two-core telephone line 丨 8 through the built-in modem 丨 4 and establish a radio frequency (RF) connection 17. The computer 1 3 can be any type of device, such as a laptop, a desktop computer, or a PDA. It has a built-in dial-up modem 14 that complies with ITU V. 90 specifications and operates at speeds up to 56 kbps. It should be noted that other plastic modems, such as the slower V · 34 type mentioned in 15 200427299 mentioned above, can also be used in the above communication methods. The wireless connection interface base 1 1 'is connected to the telephone company's central office and the public telephone network (pSTN) by plugging into a wall telephone socket 16 2 core telephone line 15'. The wall telephone socket 16 is typical rj 1 1 connector. -The base 11 and the remote wireless unit 12 communicate with each other through a radio frequency (rf) link 17. The RF link 17 transmits standard audio channels, which include the 4kHz 4kHz fundamental frequency spectrum frequency, which is also the spectrum range occupied by audio signals (for example, V.90 modem signals). Therefore, the data signal can be transmitted from the radio frequency base 11 to the remote wireless unit 12 through the wireless communication system (and vice versa). The range of this RF link may vary, but it is basically a few hundred feet or more. After demodulating the signal, this data signal is plugged into the RJ 1 1 telephone line socket both at both ends through the two-core telephone line 18 and transmitted between the remote wireless unit _ 12 and the computer 13. _ Base (also known as proximal unit) Figure 2 is a block diagram of the base 11. In the base 11, the two sets of circuits closest to the central office of the telephone are: the hot-wire interface 20 and the hybrid circuit 21. The telephone line interface 20 is also referred to as a data access split (DAA), which is connected to the central telephone equipment (not shown) through the telephone line 15, wall socket 16 and twisted-pair telephone line. 16 200427299 Telephone interface 20 includes a snoring detector, a hook switch, a DC (direct current) circuit maintenance circuit, and a separate transformer; a device (not shown). For the circuit system of the above-mentioned telephone interface 20, please refer to US Patent Application No. 09 / 658,049 'The name is Wireless Modem (Wireless Modem), not much to say here that the moon composite circuit includes a resistive composite and operational amplifier — (Not shown) The 'composite circuit 21 converts a two-core telephone operation into a four-core telephone operation. The most special function of the composite circuit 21 is: it can separate the signals flowing in two opposite directions at the same time on this two-core telephone line (so-called, full-duplex operation), and make it different in Shandong Signals can be obtained on the signal lines (four cores) 22 and 23. The # 5 tiger input (from the Central Bureau of Electrical Activity) appears on the signal line 2 2, and the output signal is output by the signal line 2 3. The composite circuit 21 is a Bridge circuit; therefore, the two signals of signal lines 22 and 23 can be separated only if the impedances connected to this bridge circuit are properly matched. However, it is necessary to consider that impedance mismatch is possible because it can make signal line 23 The signal becomes a signal from the local response of the telephone company's central office, and the "echo" appearing on the signal line 2 2 will be added to this input signal, so that the amplitude of the generated signal 24 will be several times the expected signal amplitude. High. The signal 24 generated by the echo can cause the RF transmitter 25 to overload and non-linear distortion. After the non-linear distortion is destroyed, the echo embedded in the signal 24 will not have The ground is eliminated by the echo canceller in the computer 1 3 modem 14. Therefore, in order to reduce overload and non-linear distortion, the present invention provides an AGC circuit 26. It is located between the composite circuit 21 of the base and the RF transmitter 25 The AGC circuit 26 includes a 17 200427299 peak amplitude detector, which provides a time constant long enough so that the output signal 27 can substantially maintain a constant peak amplitude within the linear amplification range of the RF transmitter 25. Because the AGC circuit 26 reduces non-linear distortion, the RF link 17 becomes basically imperceptible to the signal of the modem. Therefore, the echo canceller in the modem μ can be eliminated, and in some cases In the middle, all echoes appearing on the composite signal line 22 can be completely eliminated. 'The AGC circuit 26 can also maintain the copper < W depression amplitude of the output signal 27 to prevent it from falling to a very low value to meet a very long distance. The loop of electricity and public central bureau. Low FM amplitude will lead to the low signal-to-noise ratio of radio frequency. When AGC circuit 26 is used in many intermediate frequency (IP), sexual distortion is not The problem is that the AGC circuit 26 operates at a high frequency, and its linearity requirements are very strict. The solution can be to use a linear connection device to control the voltage to change the gain, or to use lightning. Step attenuar (resistive step attenuaror): i: 7 丄 /, j are controlled by digital commands. The gain can be controlled directly or by feedback. The control system includes measuring the input voltage 2 4, And by adjusting the voltage M, say: S to reach a constant output signal 27. In other words, the feedback control system I guess the output signal 2 7 and first adjust its gain or attenuation by adjusting its gain ^^ 0 The purpose of the AGC circuit 26 is to obtain a fixed gain (or attenuation) setting 'to make the signal channel better in normal operation. However, the use of V. 34 and V. 90 data systems requires an initial sequence (eg, a handshake procedure) to make this process complicated. For bidirectional transmission, the initial procedure consists of several steps that last several seconds. Among them, since the amplitude of a transmission signal changes, signals transmitted in two transmission directions also change. The initial process will set the gain value of the system for subsequent data transmission. This makes it necessary to set the gain value of the AGC circuit 26 before the first handshaking starts. Because if this is not the case, the signal amplitude set by the initial program of V.34 or V.90 will be changed by AGC, that is, the AGC will change the level set by the initial program to different data, so that The initial program becomes useless. This can be accomplished by measuring the dial tone or DC current level obtained from the telephone company's central office. The first signal received is a dial tone, and its level is set by the standards body. Another method is to measure the DC current, because the DC current is inversely proportional to the attenuation of the return trip. In other words, the attenuation of the circuit can be measured from the DC current. It has a fixed gain relationship with the transmission level of the data signal. Therefore, the dial tone can be used to set the gain value of the AGC circuit 26 (in a direct or feedback manner) to generate a better voltage close to the subsequent data transmission. The gain relationship between the dial tone level and the voltage 2 7 can be determined experimentally, using the echo solution of a general loop. Abnormally large echoes may require a lower voltage of 27 to avoid the increase of non-linear distortion in the RF channel. This can be done by increasing the value of X, for example, 1 d B at a time. Defective echo cancellation, thermal noise (with poor signal-to-noise ratio), and radio wave interference are all sources of transmission errors. These factors can cause the modem 14 to return to half-full duplex operation, reducing data transmission speed (for example, from 56 kb / s) and / or causing automatic retransmission requests to require retransmission of data signals. 19 200427299 _ ,: The device 25 converts the signal into a modulated RF signal receiver 38, and converts the modulated RF signal into data. The μ transmitter 25 and the RF receiver 32 operate at different frequencies. J: Connected to the shared antenna 29 through the duplexer 60, and the antenna 29 transmits the $ cycle frequency j Lu to, Yin Po Yi Lu Zhi, to Tu Zhi ”, line early 7012, or receive from the remote helmet line unit 1 FM signal of 2.

Many techniques can be used to modulate the radio frequency signal of the radio frequency transmitter 25, including FSK modulation. This technique is also widely used in some digital radio mobile phones (brothers). Regarding FSK ', for example, the V90 data signal' is a frequency converter (Deviator) used directly on the RF transmitter 25. This frequency modulator performs FSK modulation on the data signal. Taking the data signal of V.90 as an example, it can be directly applied to the frequency modulator of the RF transmitter. As far as the FM circuit is concerned, it is easy to get good linearity and low distortion. If necessary, the signal voltage can be lowered to further reduce distortion. However, this also reduces the signal-to-noise ratio to the value required for a V.90 signal. At the same time, relatively speaking,

The F S K channel is regarded as a more stable transmission medium. Its fundamental frequency gain is essentially independent of signal size (for example, signal degradation). The microprocessor 61 controls the functions of the base 11 and talks with the telephone line interface 20, the radio frequency transmitter 25, and the radio frequency receiver 38. The microprocessor 61 is also responsible for transmitting or receiving control signals to or from the remote wireless unit 12. In operation, an external caller (input telephone) operates a ring detector on the telephone line interface 20 to generate a ring indication signal 62. The microprocessor 61 transmits the ringing indication signal 62 to the remote wireless unit 12 on the wireless link, and its beep switch 3 9 will operate in response to the received data. At this time, the telephone call initiated by the other party 20 200427299 to 'computer 13 will generate a hook switch control signal transmitted from the remote wireless unit 12 back to the base η, and the microprocessor will control the signal via the hook switch at this time. 63. Hook off (h0〇k-0ff) occurs on the line interface 20, that is, the condition of receiving a call. The microprocessor 61 is also responsible for automatically selecting a relatively quiet, interference-free RF channel from all 60 available channels at 900 MHz. FIG. 3 is a block diagram of a remote wireless unit 12 circuit system. The circuit system includes an antenna 30, which receives an analog signal from the base u via radio frequency 17, and transmits the analog signal to the base via radio frequency 7 . The duplexer 31 separates the two signals by roaming different channel frequencies of the RF signals in the opposite two directions (to / from the base "), and connects them to the RF receiver 32 or the RF transmitter. 3 3. In turn, the wireless unit 12 includes a microprocessor 34, which controls the general operation of the remote wireless unit 12. In addition, the microprocessor 34 receives a signal 35 from the hook switch trigger circuit 36, and sends out a ring indicator signal 37 to control the ring driver 38 and the snoring switch 39. The microprocessor 34 also communicates with the microprocessor 61 of the base 11 (Fig. 2) through the radio frequency connection 17. The radio frequency receiver 32 sends a demodulated modem data signal 40 from the telephone central office to the composite circuit 4 丨. The radio frequency transmitter 33 receives a modem signal 42 (originated from the modem 4) from the composite circuit 41. The composite circuit 41 is used as a four-core to two-core converter, which combines the transmission signal 40 and the reception signal 4 2 (four-core) so that they can be transmitted to the two-way telephone line 18. The composite circuit 41 is similar to the composite circuit 21 200427299 21 of the base 11 and has a balanced impedance Rb and two operational amplifiers 43 and. The balanced impedance R b almost matches the impedance of the line terminal 14 of the modem 14. Because different modems may have slightly different terminal impedances Rt, a fixed value of the impedance Rb may not be sufficient to balance the composite circuit, which will cause the composite circuit to produce an echo. These echoes are basically small in the circuit 21 in the six base 11 of the car. If these echoes cause the circuit of the radio frequency amplifier 33 to be overloaded, then the AGC circuit 45 of the circuit similar to the base can be added to the remote wireless Module 12. The trigger voltage 46 of the hook switch trigger circuit 36 becomes zero volts as the hook switch in the modem 14 is turned on ("hook on"). After the modem 14 is disconnected (communication is started), the internal switch of the modem 14 is turned off 'and a DC current starts to flow from the battery voltage + Vb of the remote wireless unit 12, and flows through the remote wireless unit The resistance R j Rb, R2 and the modem 14 (the loop maintains electrical snow resistance (same as the circuit in the telephone line interface 2.). The voltage == positive value, and the hook switch trigger circuit 36 will hook switch The control voltage 35 is initially ^. The hook switch control voltage 35 is in the telephone line interface 20 of the base, and the hook switch is operated (coming, hooking off, and status). Then the incoming call transmitted by the central office is generated. The ringtone is not the voltage 37, as mentioned above, it can be used to drop from the 敕 & chao sound driver 38. The ear drive 1 38 operates normally, but through the piezoelectric transducer (not shown), The generation-listening = age sound "; the remote wireless unit 0 in the system 10 can hear the ringer circuit of the modem 14 in the bell brain 13. The C number is used to operate the electricity-times after being converted to high voltage, and then Applied to 22 200427299 line 1 8 through the 3rd ear switch 3 9 in the transformer 49. From the wireless chip The ring signal 4 8 has a higher frequency (up to several KHz) than the normal ring signal (16 to 68112) from the central office of the telephone to operate the ring circuit inside the modem 1 4. Therefore, the ring driver 3 8 The high-frequency circuit is used to replace the low-frequency circuit. Because the low-frequency ringer circuit is related and expensive, sometimes it can be omitted. Such a device cannot dial into the modem and its related computer at the same time, which makes it impossible to receive when the mobile dials. Ongoing fax and computer access. The remote wireless unit 12 (Figure 3) can get power from a battery (not shown). This battery can be provided when the remote wireless unit 12 is placed in the base. Charge in the cradle. Follow the rules of standard wireless phones. 'Every time the remote wireless unit is placed in the cradle to charge, the password can be changed. This will prevent unauthorized orders from other remotes. You can access this base by intercepting it. Another way of power supply is to obtain the required operating voltage from the computer through a USB cable. If you use this method, the password is obtained in the same way as described above. The method is different, such as using a fixed password and storing this password in EEPR0M 56 (electrical phi sub-programmable read-only memory) of the remote wireless unit 12. In addition to using a cable to connect to the portable The USB connector of the computer's remote wireless unit 12 can also include a USB connector, such as the wireless stick i0a (wireiess stick) in Figure 4. The wireless stick i〇a can be directly plugged into a portable computer. Phone Each end of the wire 18 (not shown) includes an RJ 11 plug, which can be used to connect the wireless stick 10a to the input port of the portable computer. 23 200427299 As shown in Figure 4, the remote wireless Another embodiment of unit 丨 2 includes a personal computer memory card international association (pers〇nalC〇mputer

Memory Card International Association (PCMCIA) card 1 Ob and use the power of portable computer l3. In this configuration, the remote wireless unit 12 can be plugged into a portable computer 1 3. In this way, the portable computer 13 can use the PCMCIA card 10b to provide the power required by the remote wireless unit 12 to establish a wireless connection. The data signal between the data terminal of the portable computer 1 3 and the p c μ CIA card 10 b as a wireless connection can be transmitted through a telephone line. I. Phone features: Wireless connection. · Dual-function wireless communication system 1 〇 It can include the same functions as standard wireless phones. . These items may be included in the wireless communication system 10, which allows the wireless communication system 10 to have a dual function, that is, it can be used to transmit sound like a radiotelephone or to transmit data as described above. FIG. 5 is a block diagram of a dual function radiotelephone. Switcher $ 2 is used to switch the functions of wireless phones and wireless modems. Switch control h number 5 1 is used to identify the hook switch controller 3 5. When the modem 4 is not connected to the telephone line 18 (as shown in Figure i), the voltage 46 is zero and the switch 5 2 connects the RF receiver 3 2 to the speaker $ * and the microphone η to the RF transmitter 33 . At the same time, the signal 35 indicates that the micro-processing is one input terminal of the internal gate or gate (OR gate), and the other input is enabled by the ρ 〇 〇 N E button of the radio telephone microphone. 24 ^ No. 3 5 can be used to stay -e value private + Zhuo "whether it is used in the phone or data search" to press or remove the extension is especially θ,, Τ Yilu Road (Compander circuit). 'Well, when used in a radiotelephone, this unit will use the tone (/ blC) stretch state to improve the signal-to-noise ratio during voice transmission. In the text, when the indenter receives sound (not shown in the figure), it includes a < compressor (as shown in Fig. 2) for the rotation signal 2 7 and a radio frequency receiver 3 2 (as shown in Fig. 3). (Shown) The extender of output 4 〇. Stretching causes a small amount of non-linear distortion, which is detrimental to data transmission. The stretcher also causes a small gain change in the transmission channel, which is called tracking error, which is harmful to the beginning of communication of V.34 and V.90 data transmission. Fortunately, the indenter is not required for data transmission, because the AGC circuit 26 will deal with the problem of level changes. Therefore, the extruders should only be removed on the date of data transmission. The AGC circuits 26 and 45 need not be removed when the phone mode is operating. '> When the handset is charged in the cradle provided in the base 1 1' The remote wireless unit 12 (telephone handset) of the dual-function radio telephone operates on a battery. The telephone handset 100 of Fig. 6 is an existing example. More specifically, the standard radiotelephone can also be used as a wireless communication link 10 to provide services to transmit data after adding the circuits shown in Figs. 2 and 3. At this time, the handset and telephone jack (RJ 1 1) are assembled to connect with the computer modem. As shown in FIG. 7, the present invention can also be applied to a two-line radiotelephone. In this way, 'the wireless telephone described above will have two separate telephone lines, one of which will only provide voice signals (radiophone). The other is a data-only signal (wireless connection), or a voice and data signal (dual function 25 200427299 radiotelephone). The circuit system of FIG. 7 is used to establish and provide a wireless connection as shown by a PCMCIA card 10b or a USB wireless stick 10a. Another embodiment uses a single telephone line to establish a wireless connection. This embodiment may include two remote wireless units as shown in FIG. 7: one is a telephone receiver and a portable wireless link unit. The phone line can be used for telephony applications to transmit voice or data over a wireless connection, but not for both voice and data. It is conceivable that a standard radiotelephone can be modified into a dual-function radiotelephone using the present invention. The invention is not limited to the software or hardware configuration shown in Figs. The present invention is not limited to the above-mentioned transmission data through the radio frequency band, or the above-mentioned specific modulation technology. The above embodiments are merely examples for convenience of description. The scope of the rights claimed in the present invention should be based on the scope of the patent application, not limited to the above embodiments. V. Brief Description of Drawings Figure 1 is a block diagram of a wireless link. FIG. 2 is a block diagram of a base for establishing a wireless link. Figure 3 is a block diagram of a remote wireless unit used to establish a wireless link. Figure 4 is a schematic diagram of establishing a wireless connection by using a PCMCIA card and a USB stick. Figure 5 is a block diagram of a remote wireless unit of a dual function wireless telephone. 26 200427299 Figure 6 is a schematic diagram of a dual function wireless telephone. FIG. 7 is a schematic diagram of a wireless telephone system for another functional purpose.

Description of drawing number 1 0 wireless communication system 10a wireless rod 10b PCMCIA card 11 base 1 2 remote wireless unit 13 computer 1 4 modem 1 5 two-core telephone line 1 6 telephone socket 1 7 radio frequency connection 1 8 two-core telephone line 20 Telephone line interface 2 1 composite circuit 22 signal line 2 3 signal line 24 signal 25 RF transmitter 26 AGC circuit 27 output signal 29 antenna 3 0 antenna 3 1 duplexer 32 RF receiver 3 3 RF transmitter 34 microprocessor 3 5 signal 3 6 hook switch trigger circuit 3 7 ring indicator signal 38 beep driver 39 beep switch 40 modem signal 4 1 composite circuit 42 modem signal 43 operational amplifier 44 operational amplifier 45 AGC circuit 46 trigger voltage 48 beep signal 49 Snoring transformer 5 1 switch control signal 52 switch 54 speaker 55 microphone 56 EEPROM 27 200427299 60 duplexer 61 microprocessor 62 snoring indicator signal 63 hook switch control signal 100 telephone handset

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Claims (1)

200427299 Patent application scope 1. A system for transmitting data signals through a wireless communication link, which includes: a receiver that receives data signals; an automatic gain control circuit that maintains the data signals to maintain quality A constant peak amplitude and maintained within a predetermined linear amplification range during subsequent transmission; and a transmitter that receives a data signal from the automatic gain control circuit and outputs the data signal, the transmitter having the Set a linear zoom range. 2. The circuit system according to item 1, further comprising: a composite circuit that separates an input signal from a transmission line from the input signal, the composite circuit generates the data signal according to the input data signal, and outputs the data signal Data signals are sent to the auto-increment control circuit. 3 The circuit system according to item 1, wherein the automatic increase control circuit, when starting communication, uses one of the telephone links to connect tones or DC current to set the gain level of the data signal and during the communication process, This gain level is maintained at a fixed value. 4. The circuit system according to item 2, wherein if the data signal output by the composite circuit exceeds the predetermined linear amplification range, the automatic gain control circuit limits the voltage of the data signal output by the composite circuit to reduce the Non-linear distortion of the transmitter. 5. The circuit system as described in item 1, the circuit system further includes: the electric circuit should dial out in advance to benefit the package 29 200427299 a duplexer, which is used to separate the transmitted and received data signals . 6. The circuit system according to item 1, wherein the transmitter comprises a radio frequency transmitter. 7. The circuit system according to item 6, wherein the radio frequency transmitting device includes a frequency modulator for performing frequency modulation on the data signal. 8. The circuit system according to item 7, the circuit system further comprising: a circuit system for reducing a signal voltage of one of the data signals before the data signal is input to a frequency modulation device. 9. The circuit system according to item 1, further comprising: a microprocessor for transmitting and receiving control signals to a remote wireless unit, and the remote wireless unit is connected to the remote wireless unit via a wireless communication link. The circuit system communicates. 1 0. —A device for transmitting data signals through a wireless communication link, including: a near-end unit having a wired connection to a telephone line, and the near-end unit performs data with the telephone line through the wired connection Transmitting and receiving; and a remote wireless unit having a wired connection to a modem connected to a computer, the remote unit transmitting and receiving data with the modem through the wired connection, the remote wireless unit And the near-end unit communicates with each other through the wireless communication link; wherein the near-end unit includes: 30 200427299 a radio frequency transmitter for sending data signals to the remote wireless unit; and an automatic gain control circuit, It is used to maintain the peak amplitude of the data signal of the RF transmitter substantially within a predetermined linear amplification range. _ 11. The device according to item 10, wherein the remote wireless unit comprises a handset of a wireless telephone. 12. The device according to item 10, wherein the remote wireless unit comprises a personal computer memory card international association (PCMCIA) card. 13. The device according to item 10, wherein the remote wireless unit includes a universal serial bus (USB). 14. The device according to item 10, wherein the modem is used for at least one laptop computer, desktop computer, and personal mobility assistant. 15. The device according to item 10, wherein the near-end unit further comprises: a radio frequency receiver for receiving data from the far-end wireless unit. φ 16. The device according to item 10, wherein the near-end unit further comprises: a composite circuit that separates an input signal in a transmission line from an output signal. The composite circuit generates an analog signal based on the input data signal, and then outputs the analog signal to the automatic gain control circuit. 17. The device according to item 16, wherein the analog signal output by the composite circuit exceeds the predetermined linear amplification range, the 31 200427299 automatic gain control circuit limits the voltage of the analog signal output by the composite circuit to Reduce the non-linear distortion of the transmitter. 18. The device according to item 10, wherein the near-end unit further comprises a z-duplexer for keeping the transmitted and received data signals separated. 19. The device according to item 10, wherein the radio frequency transmitter comprises a frequency modulator for performing wave frequency modulation on the analog signal. 20. The device according to item 19, wherein the near-end unit comprises: a circuit system for reducing a signal voltage of one of the analog signals before the analog signals are input to the frequency modulator. 2 1. The device according to item 10, wherein the near-end unit further comprises: a microprocessor that transmits and receives control signals to the remote wireless unit through a wireless communication link. 22. The device according to item 10, wherein the remote wireless unit further comprises: a composite circuit that separates an input data signal in a transmission line from an output signal, and the composite circuit is based on the input data Signal to generate and output the data signal; wherein the automatic gain control circuit reduces the echo produced by the composite circuit on the output data signal. 2 3. — A device for transmitting data or voice via wireless communication link, including: 32 200427299 an operating device for operating the device as a wireless data link; an operating device for operating the device as a A wireless telephone; and a switching operation device for switching the wireless data link and the wireless telephone. 24. The device according to item 23, wherein the operating device that causes the device to operate as the wireless data link generates and transmits an analog signal. 25. The device according to item 23, wherein the operating device that causes the device to operate as the wireless data link generates and transmits a digital signal. 26. The device according to item 23, wherein the operating device that causes the device to operate as the radiotelephone generates and transmits an analog signal 0 33