CN1163538A

CN1163538A - Charged TV system

Info

Publication number: CN1163538A
Application number: CN 96104732
Authority: CN
Inventors: 王中东; 王慧明; 郭玮; 孔振民; 韩丽英; 严静
Original assignee: XINBAOCHENG ELECTROMECHANIC CO Ltd BEIJING
Current assignee: XINBAOCHENG ELECTROMECHANIC CO Ltd BEIJING
Priority date: 1996-04-24
Filing date: 1996-04-24
Publication date: 1997-10-29

Abstract

The charged TV system controlled through telephone system consists of front-end charging control unit, programmed exchange, user scrambling-descrambling unit, CATV front end, CATV distributing unit, telephone set and TV set. Before the user watches charged TV program, he requests via telephone to front-end charging control unit, which judges and sends the control signal via telephone lines to the user scrambling-descrambling unit to descramble the program. The advantages includes low cost and saving in radio frequency resource.

Description

Pay television system

The present invention relates to a kind of charging system of cable TV.Particularly only with the cable TV charging system of telephone wire as the uplink and downlink passage.

Pay TV is the developing direction of cable TV, and the user can watch the colourful TV programme that oneself needs in this way, and the operator of cable TV also can obtain sufficient capital to improve program quality.Pay television system depends on cable television system, need increase charging control system and increase user's interference blanking system at user side at Headend.By front end charging control system and user's interference blanking system pay TV programs is disturbed (abbreviation scrambling), make the user can't rating.And when the user plans to watch these programs, will send user request signal (also deserving to be called capable signal) to front end paying control system.After this system carries out necessary identification to this signal, send control signal (also claiming downstream signal) and give user's interference blanking system, remove interference (abbreviation descrambling), make the user can watch these programs signal.The upstream and downstream signal has two kinds of load modes in the present pay television system, a kind of be the upstream and downstream signal all by the cable TV radio frequency path, this just need be modulated into radiofrequency signal with modulating equipment with signal at the end that signals, so that transmit.And receive signal end with demodulated equipment again with its demodulation, so that identification and control.Another is that upward signal transmits by phone, and downstream signal transmits by the cable TV radio frequency path.This dual mode all need increase modulation equipment, costs an arm and a leg, and occupies certain frequency resource.

The purpose of this invention is to provide a kind of with the pay television system of telephone wire as the upstream and downstream signal path.

The present invention is by the front end charging control system, stored-program control exchange, and user's interference blanking system, the CATV front end, the CATV distribution system, and phone and TV are formed.Stored-program control exchange wherein, the CATV front end, the CATV distribution system, and phone and TV be prior art, and the front end charging control system, user's interference blanking system is a key component of the present invention.The CATV front end, CATV distribution system and TV belong to the CATV system, stored-program control exchange and phone belong to telephone system, the front end charging control system is as a user of stored-program control exchange, and user's interference blanking system then connects above-mentioned two systems, and plays the effect that adds descrambling.System work process is as follows: the front end charging control system is made of a computer and a sound card.Sound card takies a special number as a telephone terminal.When the user planned to watch sponsored program, available phone was put through this number.Recorded information on sound card in advance, the prompting user inputs password.This password is used for chargeing and management, forms password of each CU by some.Far management system software is discerned this password, and the record request time.Send the pay TV switch controlling signal by telephone wire then and give user's interference blanking system.This pay TV switch controlling signal is double-audio signal (A:1633Hz-697Hz, B:1633Hz-770Hz, C:1633Hz-852Hz, one of D:1633Hz-941Hz), send by the phone-specific transmitting ic, its frequency without use, is received and identified by the integrated circuit that collects the digits in user's interference blanking system in existing phone system.User's interference blanking system is by the signal identification division, switch sections, and filter, timing circuit is formed.The stopband attenuation of filter surpasses 30dB, and TV signal is had enough destruction, pay television channel is placed in the stopband of filter.When user's interference blanking system was not received the pay TV switch controlling signal, this road disconnected, and the RF signal is by behind the filter, and pay channel is by filtering.After receiving the pay TV switch controlling signal that is transmitted by telephone wire by the front end charging control system when user's interference blanking system, signal identification judges, and opens switch then, and filter cuts out, and this road is straight-through, and signal passes through fully.

Advantage of the present invention is: 1. cost is convenient to promote the use of at home far below similar system.2. because of the present invention has utilized phone as the uplink line, can save valuable rf frequency resource.

The invention will be further described below in conjunction with accompanying drawing embodiment.

Fig. 1: system block diagram

Fig. 2: user's interference blanking system block diagram

Fig. 3: user's interference blanking system circuit diagram

Fig. 4: ADMINISTRATION SUBSYSTEM flow chart

This pay television system is by front end charging control system (1), stored-program control exchange (2), user's interference blanking system (3), CATV front end (4), CATV distribution system (5), and phone (6) and TV (7) composition.

The main hardware equipment of front end charging control system (1) is a computer and a sound card, and software section comprises ADMINISTRATION SUBSYSTEM and system maintenance subsystem.The hardware device part: the cable TV charging system realizes that the part of controlled function is the computer that sound card is housed, it takies (or several) number, one or more speech line can be arranged, when the user plans to watch sponsored program and put through assigned number, computer is just by the sound card automatic off-hook, play cuing information, the user only needs to operate by prompting, computer is discerned the double-audio signal that subscriber dialing produces, these signals comprise user code, password, pay TV switch command etc., control subsystem is at first confirmed user code and password, correctly then send the pay TV switch controlling signal by sound card, otherwise will point out user error information, then on-hook.ADMINISTRATION SUBSYSTEM part: if sponsored program is watched in user's request, then control subsystem is correct to user code and password confirming, and after sending the pay TV opening signal by sound card, ADMINISTRATION SUBSYSTEM is recorded in management database with this user's start date, time, and this user's the state of watching is made as " opening "; If sponsored program is closed in user's request, then control subsystem is correct to user code and password confirming, and after sending the pay TV shutdown signal by sound card, then ADMINISTRATION SUBSYSTEM is recorded in management database with this user's shutdown date, time, calculate amount receivable according to predetermined expenses standard, amount receivable also is recorded in the database, and this user's the state of watching is made as " pass ".If customer requirements is checked out, can only file a request to ADMINISTRATION SUBSYSTEM by information desk, after the legitimacy verification, ADMINISTRATION SUBSYSTEM gathers this user's accounts, prints bill, and the record of this user in the database is transferred in the flowing water storehouse.User's interference blanking system (3) is by the signal identification division and add descrambling and partly form.The course of work of scrambling part is: the RF signal that cable television system transmits, be divided into two-way through one two distributor, and one the tunnel connects high pass filter, and another road connects the variable capacitance diode path, again this two-way is mixed into one the tunnel.The stopband attenuation of high pass filter surpasses 30dB, and TV signal is had enough destruction, pay television channel is placed in the stopband of high pass filter.When the no-voltage of variable capacitance diode two ends, this road disconnects, and the RF signal is by behind the high pass filter, and pay channel can't be watched by filtering.When there is voltage at the variable capacitance diode two ends (5VDC), this road is straight-through, and by (passband section level ratio stopband high about 3 is to 4dB), the user can see pay television channel to signal fully.Introduce the identification division of signal again.When no pay TV switch controlling signal, four data outputs of dialing tone identification circuit U1 (MC145436) are low level (0V), the 5th pin of U2:A (bistable circuit 74LS74) is a high level, and the 9th pin of U2:B (bistable state 74LS74) is a low level.At pay TV switch controlling signal C duration of existence, four data outputs of U1 are high level, and the output of U3:A (four inputs and door) is high level.The time U2:A state turnover (rising edge triggering) the 5th pin become low level by high level, the 8th pin of U3 also becomes low level (the 9th, 10 pin connects high level, and the 12nd pin is timing circuit output, is high level at ordinary times, and the 13rd pin is a low level).The 9th pin of U2:B is trailing edge because of input triggers, and state is constant.When control signal arrives for the second time, the 6th pin of U3:A produces rising edge, the 5th pin of U2:A is upgraded to high level by low level, the 8th pin of U3:B is given rising edge of trigger end of U2:B, and make U2: continuous the 9th pin becomes high level, finishes state variation one time, the 9th pin level of U2:B has two effects, the one, generation adds the level that is used to control the variable capacitance diode break-make that descrambling partly needs, and high level is opened pay channel, and low level is turn-offed pay channel.The 2nd, make timing circuit work.When the user watches sponsored program, may finish watching the program of oneself liking after, stop to watch and forget that the notice front end stops to charge, cause charge chaotic.For preventing this situation, designed timing circuit, after four hours, turn off pay channel automatically.Also to continue to watch as the user, can reinform front end.When the pay TV switch controlling signal arrived, U6:A (inverter 74LS04) produced low level to U4 (74177 frequency dividing circuit) zero clearing.The high level of the 9th pin of U2:B drives the power supply that a relay is connected the oscillator U7:A (timer NE556) of timing circuit behind the one-level amplifying circuit, make its vibration, U4 is behind frequency division, after the 4th hour at QA, QB, QC, four pins of QD produce high potential, make the 8th pin of U3:B become low level, the 9th pin of monostable circuit becomes low level after 5 seconds, and the 8th pin of U3:B becomes high level by low level, make the 9th pin of U2:B become low level, turn-off pay channel.When the user plans to finish to watch, available phone notice front end charging control system (1), front end charging control system (1) produces twice pay TV switch controlling signal, same process changes once the 9th pin status of U2:B, become low level, turn off pay channel, once complete rating process can be finished.

Claims

1 one kinds of pay television systems that transmit control signal by phone, it is characterized in that: use telephone wire as the upstream and downstream signal path, by front end charging control system (1), stored-program control exchange (2), user's interference blanking system (3), CATV front end (4), CATV distribution system (5), and phone (6) and TV (7) composition, the CATV front end, the CATV distribution system, belong to the CATV system with TV, stored-program control exchange (2) and phone (6) belong to telephone system, front end charging control system (1) is as a user of stored-program control exchange (2), user's interference blanking system (3) then connects above-mentioned two systems, and play the effect that adds descrambling, front end charging control system (1) is made of a computer and a sound card, sound card is as a telephone terminal, take a special number, when the user plans to watch sponsored program, available phone is put through this number, on sound card, recorded information in advance, the prompting user inputs password, this password is used for chargeing and management, form by some, password of each CU, far management system software is discerned this password, and the record request time, sends the pay TV switch controlling signal by telephone wire then and gives user's interference blanking system (3), this pay TV switch controlling signal is a double-audio signal, sent by the phone-specific transmitting ic, its frequency without use, is received and identified by the integrated circuit that collects the digits in user's interference blanking system in existing phone system, user's interference blanking system (3) is by the signal identification division, switch sections, filter, timing circuit is formed.The stopband attenuation of filter surpasses 30dB, TV signal there is enough destruction, pay television channel is placed in the stopband of filter, when user's interference blanking system (3) is not received the pay TV switch controlling signal, this road disconnects, the RF signal is by behind the filter, pay channel is by filtering, after receiving the pay TV switch controlling signal that transmits by telephone wire by front end charging control system (1) when user's interference blanking system (3), signal identification judges, and opens switch then, and filter cuts out, this road is straight-through, and signal passes through fully.

2 pay television systems according to claim 1 is characterized in that front end charging control system (1), itself take a special number of stored-program control exchange (2).

3 pay television systems according to claim 1 is characterized in that the pay TV switch controlling signal, employing double-audio signal C (1633Hz-852Hz) (or A1633Hz-697Hz, B:1633Hz-770Hz, D:1633Hz-941Hz).

4 pay television systems according to claim 1 is characterized in that the user adds the switch that descrambling system (3) has used the variable capacitance diode control filters.