TWI452897B - Cable dispenser for cable systems - Google Patents

Description

Signal distributor for cable television systems

The invention relates to a signal distributor, in particular, an Amplitude Shift Keying (ASK) method for transmitting an uplink message to control transmission of a channel signal and transmitting a downlink message by Frequency Shift Keying (FSK). To the system control terminal to monitor the channel signal.

The general cable television system transmits the channel signal by means of the playback system to generate the cable channel signal; the trunk distributor transmits the signal to the signal distributor; and the data machine transmits the uplink message of the system control terminal to the broadcast system and the trunk distributor. To the signal distributor; and the signal distributor according to the uplink message to control whether the cable channel signal is transmitted to the client television. In addition, in order to obtain the signal status of the client television, the cable television system utilizes an appropriate mechanism to pass the signal state of the subscriber television to the signal distributor back to the system control end of the cable television system operator, and at the same time, whether it is illegal. The purpose of monitoring theft.

The signal splitter of the conventional technology has the functions of controlling channel signal transmission and channel state return, and is generally performed in the FSK mode, and the channel state is transmitted back because the multiple harmonics generated during the transmission process are not easily filtered out. It will affect the specific channel screen. In addition, the signal distributor often uses the PIN diode as the part of the channel signal switching, and the cut-off effect is only about 30DB, so the signal cannot be completely blocked, so that the cable signal of the user-side television is disturbed, resulting in the user-end television. The picture of the noise snowflake is displayed, especially the higher the frequency of the channel signal is, the more serious it is.

Therefore, there is a need for a signal distributor of a cable television system that transmits uplink messages in an ASK manner and downlink messages in an FSK manner to solve the above-mentioned problems of the prior art.

The main purpose of the present invention is to provide a signal distribution device for a cable television system for receiving downlink messages and transmitting the uplink messages to cable television system operators, including a power signal separation unit, a power conversion unit, a signal mixing and separation unit, and an uplink. The ASK transmission unit, the control unit, the signal output control unit, the signal distribution unit, the hacking detection unit, and the downlink FSK receiving unit, wherein the uplink ASK transmission unit is an ASK-based uplink message generated by the control unit, and the signal mixing and separating unit is And the power signal separation unit is transmitted to the system control end of the cable television system operator to implement the monitoring function, and the downlink FSK receiving unit transmits the downlink message in the FSK mode.

The pirate detection unit of the present invention is configured to detect whether the cable TV cable of the user end is cut or stolen, thereby generating a burglary detection signal, which can be used to achieve the monitoring function, and the control unit can detect the pirate detection. When the unit detects the signal, a shutdown message is further generated to the signal output control unit for turning off the video signal without transmitting to the user terminal television, so as to immediately stop transmitting the video signal to the user television.

Therefore, the present invention can transmit an uplink message by using an ASK method, and simultaneously transmit a downlink message by using an FSK method, and utilize a high-frequency synthesis technology to generate a required low-frequency carrier, so that the output signal has no multi-harmonic problem, and thus does not interfere with the ongoing Play cable TV shows. In addition, by using the switch chip to cut off the channel signal, the coverage channel signal can be improved to 54DB without generating a snowflake picture.

The embodiments of the present invention will be described in more detail below with reference to the drawings and the <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt;

Referring to the first figure, a schematic diagram of a signal distributor of the cable television system of the present invention. As shown in the first figure, the signal distributor of the cable television system of the present invention comprises a power signal separation unit 10, a power conversion unit 20, a signal mixing and separation unit 30, an uplink amplitude shift modulation (ASK) transmission unit 40, a control unit 50, The signal output control unit 60, the signal distribution unit 70, the hacking detection unit 80, and the downlink frequency shift modulation (FSK) receiving unit 90 are configured to receive the transmission of the system control terminal (not shown) of the cable television system operator. The cable channel signal is further transmitted to the client TV LTV.

The power signal separating unit 10 of the present invention separates the line signal S1 on the cable television line into the input power source Vin and the cable channel signal, and further copies the line signal S1 into the lower level signal S3 and transmits it to the next level signal distributor (Fig. Not shown).

The power conversion unit 20 converts the input power source Vin into an output power source Vout of an appropriate voltage to supply power to the signal mixing and separating unit 30, the upstream ASK transmitting unit 40, the control unit 50, the signal output control unit 60, the signal distributing unit 70, and the pirate inspection. The unit 80 and the downlink FSK receiving unit 90 are known.

The signal mixing and separating unit 30 is connected to the cable channel signal, and separates the cable channel signal to extract the downlink signal and the video signal contained therein, and transmits the downlink signal, wherein the downlink signal is transmitted in FSK mode.

The signal distribution unit 70 receives the video signal transmitted by the signal mixing and separating unit 30 and transmits it to the signal output control unit 60. The downlink FSK receiving unit 90 receives the downlink signal transmitted by the signal mixing and separating unit 30 and converts it to generate a downlink message. The control unit 50 receives the downlink message and generates a corresponding output control message.

The signal output control unit 60 receives the video signal transmitted by the signal distribution unit 70 and the output control message transmitted by the control unit 50, and determines whether the video signal is transmitted to the user television LTV according to the output control message to provide user viewing.

The hacking detection unit 80 detects the video signal of the user TV LTV, and generates a detection signal when the video signal of the user TV LTV is cut off, for example, when the cable is cut for illegal malicious piracy, and It is transmitted to the control unit 50, and the upstream unit is further generated by the control unit 50.

The uplink ASK transmitting unit 40 receives the uplink message generated by the control unit 50, and generates an uplink signal in the ASK manner, and transmits the signal to the signal mixing and separating unit 30, and then transmits the signal to the system control terminal via the power signal separating unit 10 for implementation. Monitoring function.

In addition, the control unit may further generate a shutdown message to the signal output control unit 60 when receiving the detection signal of the theft detection unit 80, so as to turn off the video signal and not transmit to the user TV LTV, so as to immediately stop transmitting the video signal. To the user TV LTV.

2 to 7 are exemplary circuit diagrams of various units of the present invention, and it is to be noted that the second to seventh figures are illustrative of the features of the present invention and are not intended to limit the present invention. Scope, therefore, the present invention encompasses other circuit designs that are relatively identical.

Referring to the second figure, a schematic diagram of a part of the unit of the present invention includes a power signal separation unit 10, a power conversion unit 20, a signal mixing and separation unit 30, and a theft detection unit 80, wherein the power signal separation unit 10 and the power conversion unit 20 are The transformer T1, the off-line switch control chip U1, the optical coupling element U2, the plurality of capacitors, the plurality of inductors and the plurality of diodes are configured to realize the output power source Vout for converting the input power source Vin into a direct current, as shown in the figure VCC1. VCC2 and VCC3. The signal mixing and separating unit 30 and the pirate detecting unit 80 are composed of a transformer T2, a transformer T3, three resistors R2, R4, and R6, and three resistors R3, R5, and R7, wherein the transformer T2 and the resistors R2, R4, and R6 are used for separation. The TV signal TV is output, and the transformer T3 and the resistors R3, R5, and R7 are used to connect the signal TX and generate the signal RXD, and the transformer T3 is used as the hacking detection unit 80, and the signal RXD is the detection signal.

Off-line switch control chip U1 can be selected from Power Integration's commercial TNY280 chip, while optical coupling element U2 can be selected from Sharp's commercial PC817 chip.

Referring to the third figure, an exemplary circuit diagram of the uplink ASK transmission unit of the present invention, wherein the uplink ASK transmission unit 40 includes an uplink ASK frequency control unit 42, an uplink ASK data output unit 44, and an uplink ASK frequency synthesis unit 46.

The uplink ASK frequency control unit 42 includes a plurality of capacitors, a plurality of resistors, a plurality of inductors, a plurality of transistors, a plurality of diodes, a crystal oscillator, a phase locked loop wafer U3, and a micro control wafer U4 for generating a high frequency Signal, wherein the phase-locked loop chip U3 can be a FS8170 chip sold by Pucheng Technology, and the micro-control chip U4 can be a PIC16F87 chip sold by Microchip Technology. The uplink ASK data output unit 44 includes a plurality of capacitors, a plurality of resistors, a plurality of inductors, a plurality of transistors, a transformer, a surface acoustic wave (SAW) wafer U5, and an ASK transfer wafer U6, wherein the surface acoustic wave wafer U5 can be a Taiwan Shoushuo technology. The TC0219A wafer sold by the company and the ASK transfer wafer U6 are PT4450 wafers sold by Pucheng Technology. The uplink ASK frequency synthesizing unit 46 includes a plurality of capacitors, a plurality of resistors, a plurality of inductors, a transistor, two transformers, and two diodes for performing ASK frequency synthesis processing to generate an ASK signal and treating the uplink signal.

Referring to the fourth figure, an exemplary circuit diagram of a control unit of the present invention, wherein the control unit 50 includes a plurality of capacitors, a crystal oscillator, and a microprocessor chip U7, wherein the microprocessor chip U7 can be a commercially available single-chip microcontroller 89S52. .

Referring to FIG. 5, an exemplary circuit diagram of a signal distribution unit, wherein the signal distribution unit 70 includes a plurality of capacitors, a plurality of resistors, and a plurality of transformers for converting the cable television signal into eight cable separation signals, such as in the figure. IN1~IN8.

Referring to the sixth figure, an exemplary circuit diagram of the signal output control unit of the present invention, wherein the signal output control unit 60 includes eight sets of output units for converting the cable separation signals IN1~IN8 into separate output signals OUT1~8, and each The output unit is one of the eight cable separation signals, and each output unit includes a plurality of capacitors, a plurality of resistors, and a cable switch chip U8. The cable switch chip U8 can be a MASWSS0067 sold by Cobham. Wafer.

Referring to the seventh figure, an exemplary circuit diagram of the downlink FSK receiving unit of the present invention, wherein the downlink FSK receiving unit 90 includes a plurality of capacitors, a plurality of resistors, a plurality of inductors, a plurality of transistors, a crystal oscillator, and an FSK receiving chip U9, wherein The FSK receiving wafer U9 can be an FSK receiving wafer SI4330 sold by Silicon Labs.

The invention is characterized in that the wired electric signal of the cable television system operator can be controlled by the ASK method to be transmitted to the user terminal for the customer to watch, and at the same time, the state of the cable television cable of the user end is transmitted back to the cable television system operator by FSK mode. The control center to monitor whether the cable TV cable is cut or stolen.

Another feature of the present invention is that the switch chip can be used to cut the channel signal, and the cover channel signal can be improved to 54DB without generating a snowflake picture. In addition, the uplink message is transmitted using ASK, and high frequency synthesis technology is utilized to generate the required The low frequency carrier causes the output signal to have no multiple harmonics and thus does not interfere with the cable program being played.

The above is only a preferred embodiment for explaining the present invention, and is not intended to limit the present invention in any way, and any modifications or alterations to the present invention made in the spirit of the same invention. All should still be included in the scope of the intention of the present invention.

10. . . Power signal separation unit

20. . . Power conversion unit

30. . . Signal mixing separation unit

40. . . Uplink ASK transmission unit

42. . . Uplink ASK frequency control unit

44. . . Uplink ASK data output unit

46. . . Uplink ASK frequency synthesis unit

50. . . control unit

60. . . Signal output control unit

70. . . Signal distribution unit

80. . . Pirate detection unit

90. . . Downlink frequency shift modulation (FSK) receiving unit

IN1~IN8. . . Cable separation signal

OUT1~8. . . Separate output signal

R2, R4, R6. . . resistance

R3, R5, R7. . . resistance

RXD. . . Signal

S1. . . Online signal

S3. . . Subordinate signal

LTV. . . Client TV

T1. . . transformer

T2. . . transformer

T3. . . transformer

TV. . . TV signal

TX. . . Signal

U1. . . Offline switch control chip

U2. . . Optical coupling element

U3. . . Phase locked loop

U4. . . Micro control chip

U5. . . Surface acoustic wave wafer

U6. . . ASK transfer chip

U7. . . Microprocessor chip

U8. . . Cable switch chip

U9. . . FSK receiving chip

Vin. . . Input power

Vout. . . Output power

The first figure is a schematic diagram of a signal distributor of the cable television system of the present invention.

The second figure is an exemplary circuit diagram of some of the units of the present invention.

The third figure is an exemplary circuit diagram of the upstream ASK transmission unit.

The fourth figure is an exemplary circuit diagram of the control unit.

The fifth figure is an exemplary circuit diagram of the signal distribution unit.

The sixth figure is an exemplary circuit diagram of the signal output control unit.

The seventh figure is an exemplary circuit diagram of the downlink FSK receiving unit.

10. . . Power signal separation unit

20. . . Power conversion unit

30. . . Signal mixing separation unit

40. . . Uplink ASK transmission unit

42. . . Uplink ASK frequency control unit

44. . . Uplink ASK data output unit

46. . . Uplink ASK frequency synthesis unit

50. . . control unit

60. . . Signal output control unit

70. . . Signal distribution unit

80. . . Pirate detection unit

90. . . Downlink frequency shift modulation (FSK) receiving unit

S1. . . Online signal

S3. . . Subordinate signal

LTV. . . Client TV

Vin. . . Input power

Vout. . . Output power

Claims (6)

A signal distributor of a cable television system, the signal distributor of the cable television system comprises: a power signal separation unit, which is coupled to a system control terminal, and separates a line signal transmitted by the control terminal of the system into an input power source and a cable TV channel signal, and further copying the line signal into a lower level signal and transmitting to the next level signal distributor; a power conversion unit, converting the input power to an output power of an appropriate voltage; a signal mixing and separating unit, connecting The cable channel signal is separated and the cable channel signal is separated to extract the next signal and a video signal, and the downlink signal is frequency shift modulation (Frequency Shift Keying, FSK) mode transmission; a signal distribution unit receives the video signal and transmits it to a user terminal television; the next line FSK receiving unit receives the downlink signal to generate a downlink message; and a control unit receives the downlink message and generates a Output control message; a signal output control unit, receiving the a video signal transmitted by the signal distribution unit and an output control message transmitted by the control unit, and based on the output control message to determine whether the video signal is transmitted to the user television; a stealing detection unit detects the user a video signal of the television, and when the video signal of the user television is cut off, a detection signal is generated and transmitted to the control unit, and the control unit generates an uplink message; an uplink ASK transmission unit receives the Upstream message, and generating an uplink signal, which is transmitted to the signal mixing and separating unit by Amplitude Shift Keying (ASK), and further transmitted back to the system control terminal via the power signal separating unit For monitoring. According to the signal distributor of claim 1, wherein the control unit further generates a close message to the signal output control unit to close the video signal when receiving the detection signal of the theft detection unit. Not delivered to the client TV. According to the signal distributor of claim 1, wherein the uplink ASK transmission unit includes an uplink ASK frequency control unit, an uplink ASK data output unit, and an uplink ASK frequency synthesis unit, and the uplink ASK frequency control unit is used by the uplink ASK frequency control unit. To generate a high frequency signal, the uplink ASK data output unit is configured to receive the high frequency signal of the uplink ASK frequency control unit and generate an ASK frequency signal, and the uplink ASK frequency synthesizing unit is configured to utilize the ASK of the uplink ASK data output unit. The frequency signal converts the uplink message from the control unit into an ASK signal and uses it as the uplink signal. The signal distributor according to claim 3, wherein the uplink ASK frequency control unit comprises a plurality of capacitors, a plurality of resistors, a plurality of inductors, a plurality of transistors, a plurality of diodes, a crystal oscillator, A phase locked loop wafer and a micro control wafer. The signal distributor according to claim 3, wherein the uplink ASK data output unit comprises a plurality of capacitors, a plurality of resistors, a plurality of inductors, a plurality of transistors, a transformer, a surface acoustic wave (SAW) wafer, and a ASK transfers the wafer. The signal distributor according to claim 3, wherein the uplink ASK frequency synthesizing unit comprises a plurality of capacitors, a plurality of resistors, a plurality of inductors, a transistor, two transformers, and two diodes.