TW507428B - Method and system for extending broadcast coverage on a single frequency network - Google Patents

Abstract

A system for aligning the phase characteristics of N identical digitized audio program signals distributed from a studio to N broadcasting stations via N nine division multiplex (TDM) communication signals includes N TDM multiplexers, each of which (i) multiplexes a digitized audio program signal into at least one channel of a TDM communication link established between the studio and one of the N broadcasting stations, and (ii) multiplexes a timing signal into another channel of the TDM communication signal. A TDM de-multiplexer at each of the broadcasting stations extracts the digitized audio program signal and the timing signal from the corresponding TDM communication signal. A timing signal comparator compares the extracted timing signal to a local timing signal that is delayed by a precise and adjustable amount, and produces an offset time corresponding to the comparison result. The delay adjust circuit dynamically adjusts the delay of the TDM signal as a function of the offset time, preferably so as to drive the offset time to substantially zero. The timing signal at the studio and the timing signals at each of the broadcast stations are provided by an existing time distribution network.

Description

507428 Amendment Supplement V. Description of the invention (The present invention is about electromagnetic signals in broadcasting, slaves are sufficient for signal broadcasting. Broadcasting covers a domain, and service providers can generally use the Gekoukou Geographical Area to all geographic areas, or She has two disadvantages: "< ... = Γ: technical reasons. For example, in many phases:", the developed number is based on the "line of sight," Function. This means that signals cannot be sent on the general horizontal line (relative to the launch site). Moreover, geographical obstacles such as construction and mining, bridges 'land stacks, etc., will cover the geographic area of the launch site' economically , Most of them are smaller, with lower power transmission! The location is lower than generating the same amount of power and / or providing the same broadcast coverage area: It is often cheaper to own and operate a single location. Moreover, the Federal Communications Association considers it beneficial to apply for transmitting existing, different frequencies The location is changed to a place that all operates on the same frequency, because this action can open the band width within a commercial night that has already been congested. Figure 1 Α description covers One of the close-up areas is a single, high-power transmitter, and Figure 丨 B illustrates six lower-power transmitters, each of which receives a program fed from a central studio location, covering approximately the same t-related R area. The low-power transmitter TXn covers a region Rn (for all η from 1 to 6). One of the disadvantages of the multi-transmitter structure in Figure 1B is an overlapping area (ie, an area covered by one or more transmitters). In this way, the signal strength from different transmitters is the same.) Receivers within the range are easy to receive multiple signals. Figure 2 illustrates that the receiver is located near one of the overlapping areas μ between the two transmitters Ding and Ding]. Click here-4- This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm). The legend illustrates that each transmitter passes through a public switching telephone network called a PSTN) m (or E1) digital circuit to ^ The machine chain (referred to as STL for short) can be received from the central broadcasting room χ—audio ^. Because the TX12STL network path is shorter or shorter than the network path of τχ2, the audio program sent by TX1 & TX2 will not It is on the same date ^. The reception of near overlapping areas · The effects are received from its foot a plurality of signal transmitters, so the demodulation output will "jump ,, delay between the two forms of the same time of the audio program. Some prior art systems can insert a fixed delay into the STL path to balance the path delay. However, when an STL is performed via ρ§τΝ (rather than via a dedicated line), the STL path delay will not remain fixed due to different reasons, such as re-traversing the communication chain, changing communication conditions, data buffering, and PSTN switching Different processing delays. An object of the present invention is to actually overcome the disadvantages and obstacles identified above. The present invention includes a system for calibrating the phase characteristics of a digital audio program with the same N. The signal is distributed from a broadcasting room to an N broadcasting station via an N-time division multiplexing (TDM) communication signal, and the broadcasting room and the n broadcasting stations each receive signals. An accurate timing signal includes an N TDM multiplexer in the studio, where each N multiplexer can multiplex the digitized audio program signal into the TDM sent from the studio to an N broadcast station The communication signal is in at least one channel 'and (ii) the accurate timing signal received by the studio can be multiplexed into another channel of the TDM communication signal, that is, for each of the N broadcasting stations, (i ) In order to eliminate the TDM demultiplexer from the digitized audio program signal corresponding to one of the N TDM communication signals and the timing signal of the studio, -5- This paper standard applies to China National Standard (CNS) A4 specifications (210X 297 mm) y-day correction A7 B7 V. Description of the invention (ii) A timing signal comparator for comparing the timing signal of the studio with a local timing signal delay compensation to produce a comparison result, and for generating the corresponding comparison Knot One compensation time; and Chiu) effectively adjusting one of the communication signals to compensate for the effect of time delay of the TDM 'entire circuit' wherein the delay adjustment circuit preferably is substantially non-negligent system can be hit. The present invention also includes a method of calibrating the phase characteristics of N identical digital audio program signals distributed from the broadcasting room to the N broadcasting station through N time division multiplexing (tdm) communication signals. The broadcasting room and the N broadcasting station each receive one The accurate timing signal includes: multiplexing the digitized audio program signal into at least one channel of a TDM communication signal transmitted from the studio to one of the N broadcasting stations; multiplexing the accurate received by the studio The timing signal enters another channel of the TDM communication signal; and for each N broadcasting station, the digitized audio program signal and the broadcasting room timing signal are eliminated from a corresponding signal of the N TDM communication signal; The broadcasting room timing signal and a local timing signal to generate a comparison result and generate a compensation time corresponding to the comparison result; and vigorously adjust the delay of the TDM communication signal as one of the effects of the compensation time in order to drive the actual compensation time Is zero, and including this step dynamically adjusts the phase delay of the audio program in a substantially impeccable manner, where The distribution network further comprises the step of receiving the accurate timing of each of the signals from a pre-existing time. -6- This paper size applies Chinese National Standard (CNS) A4 specifications (210 X 297 mm) 4 4 Five invention descriptions (8 2 overtake, calibrated through N time division multiplexing (DM) communication chain from the studio 2 A system equipped with the same phase characteristics of the digital audio program signal of N broadcasting station N. The broadcasting room and N broadcasting station each receive a correct timing signal. At this time, 'the first includes and then the TDM multiplex transmission in the broadcasting room N. Each One N multiplexer can: transmit digital audio program signals into at least one channel of the mutual TDM communication chain established between the studio and one N broadcast port, and (丨 丨) can be multiplexed for two outputs. The accurate timing signal received by the studio enters the second and the TDM communication chain. Each N broadcasting station can include a TDM demultiplexer, which can be compared with a delay adjustment circuit. The demultiplexer can A corresponding chain of the N TDM communication chain eliminates the digital audio program signal and the broadcasting room, = signal. The timing signal comparator can compare the timing signal of the broadcasting room with the signal of one round of the clock and generate a compensation time corresponding to one of the comparison results. .J delay adjustment circuit can be powerfully adjusted The delay of the digital audio program signal is complement: time-effect. According to an example, the delay adjustment circuit can dynamically adjust the delay of the digital frequency private signal so as to drive the compensation margin to zero. Η You press the invention As another example, the delay adjustment circuit is virtually unassailable. The term "unassailable" means that a delayed correction can be achieved without loss of data or generation of a gap in the delayed digital data portion. The series according to the present invention In another example, a "global positioning and receiver can provide accurate timing signals. (〇δ) According to another example of the present invention, the TDM communication chain includes ~ τ, 2-strong architecture circuit. According to another example of the present invention, the TDM communication chain is essentially unidirectional, such as W / 7] > Day Correction V Supplement | m V. Description of the Invention (5—) " " " — This time signal And program audio signal data flows from the broadcasting room to a corresponding station of the N broadcasting station. According to another example of the present invention, the system further includes an audio card in the broadcasting room and one in each of the N broadcasting stations. Audio Among them, broadcast 1: bone frequency card can digitize an analog audio program, and each broadcasting station audio card can convert the digital audio program to analog audio program. According to another example of the present invention, each audio card is in the relevant audio The frequency of the signal frequency can maintain the consistent linear phase delay of the audio signal, thus maintaining a constant audio signal group delay. According to another example of the present invention, the audio card includes at least one FIR filter to ensure a constant group delay. The drawings, by way of example, illustrate the present invention, in which: Figure 1 A illustrates a single, high-power transmitter covering a related R-region; Figure 1B illustrates the joint provision of about six of the same coverage as the transmitter of Figure 1A Lower power transmitter; Figure 2 illustrates a location close to the overlap between the two transmitters shown in Figure 1B, and Figure 3 shows a block diagram of a signal distribution system. Figure 3 shows a block diagram of a preferred example of a signal distribution system 100 for calibrating the phase of N identical digitized audio program signals distributed from a studio to a ν broadcast station via an N-time division multiplex (TDM) communication chain. characteristic. The description of the system 100 includes a broadcast room 102, a first broadcast location 104, and a second broadcast location 106. Although other examples of system 1000 may include numerous (i.e., some integer N) broadcast locations. Studio location 102 includes a central time reference -8-This paper size applies to China National Standard (CNS) A4 (210 X 297 mm)

Fifth, the day of tomorrow (6) 110 'an audio program source 112, a first TDM multiplexer 114, a first transmitting (hereinafter referred to as TX) audio circuit 116, a second TDM multiplexer us and a second τ X Jin Frequency circuit 120. A generalized example of a system with N broadcast locations includes a N TDM multiplexer and an N TX audio circuit, so that each broadcast location can include a TDM multiplexer / audio circuit pair at the studio location 102. Therefore, according to the illustrated example, the studio location includes two Tdm multiplexers / frequency pairs: 114/116 and 11 8/120. Each TDM multiplexer / audio circuit pair can receive a central timing signal 122 from a central time reference 11 and an audio program signal 124 from an audio program source 112. According to the first TDM multiplexer / audio circuit pair 114/116, the TDM multiplexer 114 can receive the timing signal 122 and the τχ audio circuit 116 can receive the audio program signal 124. According to the second τOM multiplexer / bone frequency circuit pair 1 18/120, the TDM multiplexer 118 can receive the timing signal 122 and the τχ multiplexer circuit 120 can receive the audio program signal 124 ^ About each TDM multiplexer / Audio circuit pair. The τ X audio circuit can digitize and process the received audio program signal 124, and can provide a digitized signal 126 to the corresponding < TDM multiplexer. The Τχ audio circuits 116 and 120 can use digital signal processing (hereinafter referred to as DSP) technology, for example, a finite impulse response (hereinafter referred to as FIR) filter to maintain a constant group delay, and therefore maintain accurate and Uniform phase calibration. The tdm multiplexer can distribute the digitized signal 126 and the real-time k number 122 in a plurality of existing time slots in an output TDM signal. The first TDM multiplexer 118 may generate a first TDM transmission signal 128 'and the second TDM multiplexer u0 may generate a second tdm transmission signal 129. Therefore, the data packets sent via the TDM transmission signals 128 and 129 can carry the digitized program signals corresponding to the audio signal program signal 124 ** 9-This paper is suitable for financial standards S 8 standards (CNS) A4 specifications (21〇 ^ 97 Male |) 507428

Patent Application No. j〇i9102903 $ Correction Sheet (June 91) Α7 B7 V. Description of Invention (7) 126, together with a timing signal 122 which can digitize the signal 126 to "time tag". In other words, the timing signal 122 sent in conjunction with the digitized signal 126 in the TDM output signal can provide information on when the studio location 102 has generated a digitized signal 126. The first broadcast location 104 includes a first TDM demultiplexer 130, a first local time reference 132, a first timing signal comparator 134, a first delay adjustment circuit 136, a first delay compensation 137, and a first reception (hereinafter referred to as RX ) Audio circuit 138 and exciter / transmitter assembly 139. The first delay adjustment circuit 136 may receive the first TDM transmission signal 128 generated by the TDM multiplexer 116 at the studio location 102, and may provide the TDM signal 128—a delay form to the TDM demultiplexer 130. The TDM demultiplexer 130 may eliminate the digitized signal 126 and the timing signal 122 from the appropriate time slot of the TDM transmission signal 128 to generate a recovered digitized audio signal 140 and a recovered timing signal 142, together with the local time reference 132. One of the local timing signals 144 is generated and subsequently delayed by the delay compensation 137. The timing signal comparator 134 may generate a time compensation signal 146 corresponding to one of the time differences between the recovery timing signal 142 and the local timing signal 144. The delay adjustment circuit 136 can receive the time compensation signal 146 and can adjust the amount of delay it adds to the TDM signal 128 to drive the time compensation signal 146 to zero. To drive the time compensation signal 146 to zero, the following equation must be satisfied: [delay of delay compensation 137] = [delay of delay adjustment circuit 136] + [PSTN delay] The delay of delay compensation 137 must be greater than the maximum expected PSTN delay. If all the broadcasting stations output the broadcasting station program audio 126 at the same time, the delay compensation 137 must be the same in all broadcasting stations. According to the alternative embodiment, for different -10- paper sizes, the Chinese National Standard (CNS) A4 specification (210 X 297 mm) is applied. 5. Description of the invention (8) Broadcast stations can set delay compensation 137 separately. Time output program audio 126 to different radio stations. This device allows the overlap ^ between adjacent broadcast stations to be slightly modified. For example, it is preferable to place the overlapping area at the same power position between two adjacent broadcasting stations. If two adjacent broadcasting stations have unequal power, the equivalent power position is not equidistant from each broadcasting station, but is located closer to the lower power broadcasting station. By adjusting the delay provided by the delay compensation 137, the overlap area can be completed to precisely occur at equal power positions. & An example of a delay adjustment circuit 136 is disclosed in the specification of U.S. Patent Application No. 5,818,769. The delay line, which is preferably in the unassailable mode, can produce a throughput delay that changes to a series of digital data elements. The term "invulnerable" means that a delay change can occur without loss of data or a gap in the output series of the delayed digital data element. The delay line can also operate in a "non-invulnerable" mode during which time the digital data element is licensed The loss of data in the series may allow a delay change to start immediately when there is a gap in the series of digital data components. The audio circuit 138 can receive the digitized audio signal 140 and generate a coefficient-bitized audio signal 140. One of the effects of processed audio # 号 14 8. The exciter / transmitter 13 9 can receive the processed audio signal 14 8 and generate a modulated carrier signal 150 which is transmitted by a parallel antenna assembly 152. The first broadcast location 106 includes a second TDM demultiplexing Industrial unit 160, second local time reference 162, second timing signal comparator 164, second delay adjustment circuit 166, second delay compensation 167, second receiving (hereinafter referred to as rX) audio circuit 168, and an exciter / transmitter Machine assembly 169. In general, the components of the second broadcast location 106 are operable and are substantially in accordance with the first broadcast location -11-this paper Of the applicable Chinese National Standard (CNS) A4 size (210X297 mm) *** ·· I Shu _ a suspected yf < rM ^.

The private components are the same. The second delay adjustment circuit 166 can receive the second TDM transmission signal 129 generated by the TDM multiplexer 120 at the studio location 102, and can provide the TDM signal 129. A delay shape = fDM demultiplexer 160. The TDM demultiplexer 160 can eliminate the digitized signal 126 and the timing signal 122 from the appropriate time slot within the D ^ transmission ^ number 129 to generate a recovered digitalized frequency signal 170 and a recovered timing signal 72, together with A local timing reference 162 is generated and subsequently delayed by a delay compensation 167 ^ a local timing signal 17 4. The timing signal comparator 164 may generate a time compensation signal 176 corresponding to one of the time differences between the recovery timing signal 1 72 and the local timing signal 74. The delay adjustment circuit 166 can receive the time compensation signal 176 and can adjust the amount of delay added to the TDM signal 129 to drive the time compensation signal 1 7 6 to zero. To drive the time compensation signal 17 6 to zero, the following equation must be satisfied: [ The delay of delay compensation 167] = [the delay of delay adjustment circuit 166] + [psTN delay] The delay of delay compensation 167 must be greater than the maximum expected PSTN delay. If all broadcasting stations output the program broadcasting 126 of the broadcasting station at the same time, the delay compensation 167 must be the same in all broadcasting stations. According to an alternative example, delay compensation 167 ′ can be set for different broadcasting stations individually to output program audio 126 to different broadcasting stations at different times (as described in the first broadcasting site 104). The audio circuit 1 68 is a processing audio signal 178 that can receive digital audio signals 70 and generate coefficient bit audio signals 170. The exciter / transmitter 169 may receive the processed audio signal 1 78 and may generate a modulated carrier signal 1 80 which is transmitted by a parallel antenna assembly 1 82. The individual RX audio signals 138 and 168 at the broadcasting locations 104 and 106, each -12- This paper size applies to China National Standard (CNS) A4 specifications (210X297 mm)

Binding

5. Description of the Invention (10) Use of DSP technology, such as FIR filters, to maintain a constant group delay through one of the RS audio circuits. The constant group delay through the R X audio circuit is used to protect the accurate and consistent phase calibration of the audio program signals for broadcasting. Each N TDM signal generated by the studio location 102 can be transmitted to one of the N broadcast locations via the digital transmission channel. As a preferred example, a public switched telephone network (hereafter referred to as PSTN) can provide digital transmission channels, although other transmission media known to the skilled person can also provide such channels. According to a preferred example, the T1 circuit in the PSTN can provide digital transmission channels, although other communication transport mechanisms such as E1, ATM, TCP / IP, Ethernet, ISDN, or others can be used in the alternative. The T1 digital transmission chain from studio location 102 to a broadcast location 104 or 106 can define the TDM protocol and implement a strong framework algorithm to prevent signal interruptions due to network transmission bit errors. In general, the T1 chain includes 24 different TDM time slots, each slot transmitting eight information bits. The single frame bit system includes 24 TDM time slots per group to form a 193-bit frame. 12 The structured bits of the continuous architecture can form a unique type used by the receiving equipment to establish synchronization of the architecture. The transmission rate of the T 1 chain is 1.544 million bits per second (hereinafter referred to as MBPS), so the maximum available data rate for any single time slot is 64 bits per second (hereinafter referred to as KBPS). With T1 TDM structure, 24 different 64 KBPS channels can be sent on a single T1 chain. To increase the band width, a single channel can use more than one time slot. For example, if two time slots are used on a single channel, the channel energy can be increased to 128 KBPS. If all 24 time slots are used on a single channel, the system can achieve a maximum channel capacity of 1.536 MBPS. Central time base 110 at broadcast location 102 and broadcast locations 104 and -13- This paper size applies Chinese National Standard (CNS) A4 specifications (210X 297 mm)

Cf / Yan (month

V. Description of the Invention (11 Amendment Supplementary Local Time Base Hua Λ ^ tr \. Office at 0— 办 132 and M2 are synchronized separately to provide substantially the same time code at each location. In other words, timing The signal 122 'Local Time ## 144 and Local Time Letter i are essentially the same all the time. According to a preferred example, by using a global positioning system (S) at the broadcast location ιo2 and each of the broadcast locations 104 and 106) The receiver can perform this time synchronization. The GPS system is a network of geosynchronous orbiting satellites that are closely synchronized in time. The satellite can continuously broadcast the positioning and day time information used by the earth receiver, mainly for navigation. However, because the satellite system is synchronized in time and each satellite can broadcast its local time information, GPS can also be used to effectively time synchronize a wide range of earth locations. According to an example of the present invention, each GPS receiver is referred to as a local time source of a local frequency. The local frequency source may include a temperature-compensated crystal oscillation state, an extra large oscillator, an oscillator, a cesium oscillator, a hydrogen microwave laser, or other frequency sources. According to the situation that the GPS signal is lost for a short time, the local time source can act as a "flywheel" to maintain the system operation until the GPS signal is restored.夂 Furthermore, GPS satellites include extremely precise frequency references, and GPS receivers can recover precise reference signals from satellite broadcasts. Therefore, a Gps receiver can be used as a precision frequency source for parallel equipment, as long as the receiver remains connected to the satellites. One receiver at each broadcast location locks the carrier frequency, and therefore locks each broadcast location to a common reference. The main function of the present invention is to dynamically compensate the small delay change distribution network (e.g., public switched telephone network) between broadcast location 102 and broadcast locations 104 and 106. Ideally, the path from the central broadcasting station to each broadcasting station -14- This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 public love) " " " " " " ''- ----- V. Description of the invention (12 = ;: tv because the delay adjustment circuit in each broadcast location can be changed: two over! The delay does not lose data or insert two gaps in the data series, the system can maintain the required Equal path delay without failure. By TDM communication & time between broadcaster and broadcaster

Accuracy. For example, the use of —Tit_ = J household extension material tr also points to the road of each—broadcasting location (about absolute reference), plus or minus two microseconds later than k. There is a large borrowing: increase: σ accuracy. According to the preferred example, the system is decomposed. Two-two steps (U microsecond steps can compensate for the delay between the broadcast location and the broadcast location to make the system in the broadcast overlap area perform optimally. Press :: = to modify (such as in the 769 patent application details (Description) Delay circuit to increase or decrease V, system decomposition depends on system implementation requirements. Through TD-SCDMA communication signal for calibration, the same digitized audio program signal assigned by broadcasting station to broadcasting station Ν A system of phase characteristics includes an NTDM multiplexer, each of which can multiplex a digitized audio program signal into at least one channel of a TDM communication chain established between a broadcasting station and a broadcasting station, And ⑴) It can multiplex a certain time signal into another channel of the TDM communication signal. The TDM demultiplexer at each broadcasting station can take out the digitized = frequency two signals and timing signals from the corresponding TDM communication signals. The timing signal comparator can compare the extracted timing signal with a precise and adjustable local timing signal with a delay, and generate a comparison time sufficient to compensate the time. The delay adjustment circuit can effectively adjust the delay of the signal as a function of the compensation time, so as to better drive the compensation time to practically zero. 507428 π / year / month at the broadcasting room can be provided by the existing time distribution network. Said repair patch A7 B7 V.1 Description of the invention (13) Timing signal and timing signal element symbols at each broadcasting station Description 1 00 signal distribution system 1 02 broadcast room location 1 04 first broadcast location 1 06 second broadcast location 110 central time reference 112 audio program 114 first TDM multiplexer 116 first transmitting audio circuit 118 second TDM multiplexer 1 20 Second TX audio. Circuit 1 22 Central timing signal 1 24 Audio program signal 126 Digitized signal 12 8 First TDM transmission signal 129 Second TDM transmission signal 13 0 First TDM demultiplexer 13 2 First local time Reference 1 34 First Timing Comparator 13 6 First Delay Adjustment Circuit 13 7 First Delay Compensation 13 8 First Receive Audio Circuit 13 9 Exciter / Transmitter Assembly _ Binding-16- This paper size applies to China Standard (CNS) A4 (210 X 297 mm) 50742 \ qin- \ οα er, / '-r; r, 孑

AB 5. Description of the invention (14) 140 Digitized audio signal 1 42 Recovery timing signal 144 Local timing signal 146 Time compensation signal 15 0 Modulated carrier signal 1 52 Parallel edge assembly 1 60 Second TDM demultiplexer 1 62 Second local time reference 1 64 Second timing signal comparator 1 66 Second delay adjustment circuit 1 67 Second delay compensation 16 8 Second receiving audio circuit 1 69 Excitation circuit / transmitter assembly 17 0 Digital digitization is restored. Frequency signal 1 72 recovery timing signal 1 74 local timing signal 1 76 time compensation signal 17 8 processing audio signal 1 80 modulating carrier signal 1 82 parallel antenna assembly -17-

This paper size applies to China National Standard (CNS) A4 (210X 297 mm)

Claims (1)

507428 ° [卜 ί:,. Α8 k;…: B8 .C8 π!: D8 ~, patent application scope 1. A method for calibrating distribution from broadcast studio to N broadcasting station via N time division multiplexing (TDM) communication signal A system in which N has the same phase characteristics of a digital audio program signal, the broadcasting room and the N broadcasting station each receive an accurate timing signal, including an N TDM multiplexer in the broadcasting room, which is characterized in that each of the N multiple The unit can multiplex the digitized audio program signal into at least one channel of the TDM communication signal sent from the studio to one of the N broadcasting stations, and (ii) it can multiplex the channel received by the studio. The accurate timing signal enters another channel of the TDM communication signal, and for each of the N broadcasting stations, (i) eliminates the digitized audio program signal and one of the timing signals from the corresponding signal of the N TDM communication signal. Demultiplexer, (ii) comparing the broadcast timing signal with the local timing signal of the delayed compensation reward to generate a timing signal comparator, and generating a compensation time corresponding to the comparison result, and (iii) dynamics Ground tone Delay adjustment of the TDM communication signal is one of the effects of the compensation time on a delay adjustment circuit, and preferably, the delay adjustment circuit is virtually impeccable. 2. If the system of claim 1 is patented, the accurate timing signal can be provided by a pre-existing time distribution network. The pre-existing time distribution network includes a global positioning system (GPS) satellite network, and At least one GPS receiver can provide this accurate timing signal. 3. If the system of claim 1 is applied for, the TDM communication signal includes a T1 communication signal, and the TDM communication signal also includes an E1 communication signal. -18- This paper size is applicable to Chinese National Standard (CNS) A4 specification (210 X 297 mm) 502428 IL charge reduction I supplement V4 A BCD VI. Patent application scope 4. If the system of item 3 of the patent application scope, where The tdM communication signal is essentially unidirectional, so that the accurate timing signal and the program audio signal can flow from the studio to one of the N broadcasting stations. :> If the system of item 4 of the patent application is applied, each of the digitized audio program signals includes a frequency band sufficient to accurately transmit a high-fidelity music program, and includes a sufficient frequency to accurately transmit a high-fax Degree of electric range of music programs. 6. The system of item 5 of the scope of the patent # 7, wherein each of the digitized audio program k number can transmit at least one channel of single channel information, or each of the digitized audio program signal can transmit at least two channels of stereo information Channels. 7. The system according to item 丨 of the scope of patent application, characterized in that the audio card at the broadcasting room is the same as the actual audio card at the parent-broadcasting station. The broadcasting room audio card can make an analog audio program digital. And each of the broadcasting station audio cards can convert the digitized audio program into the analog audio program, and each of the audio cards can maintain a consistent linear phase delay of the S audio # number on a related audio signal frequency band, Therefore, a constant audio signal group delay is maintained, wherein the audio card includes at least one FIr filter to maintain the constant group delay. 8. The system of claim 1 in which the delay adjustment circuit can electrically adjust the delay of the TDM communication signal to drive the compensation time to practically zero. ^ 9 · Phase characteristics of N identical digitized audio program signals distributed from broadcasting studio to N broadcasting station via N time division multiplexing (TDM) communication signal -19- This paper standard applies to China National Standard (CNS) A4 Specifications (210X297 mm) " ------- 507428 IJjT,-I η fr (r), V'M 11 ^ j Supplement A8 B8 C8 D8 6. The method of patent application, the broadcasting room and the N broadcasting station each receive an accurate timing signal, which is characterized by: multiplexing the digitized audio program signal into the TDM sent from the broadcasting room to one of the N broadcasting stations Within at least one channel of the communication signal; multiplexing the accurate timing signal received by the studio into another channel of the TDM communication signal; and for each of the N broadcasting stations, corresponding to one of the N TDM communication signals The signal eliminates the digitized audio program signal and the studio timing signal; compares the studio timing signal with a local timing signal to generate a comparison result, and generates a compensation time corresponding to the comparison result; and dynamically adjusts the TDM The delay of the communication signal is one of the effects of the compensation time in order to substantially drive the compensation time to zero, and includes the step of dynamically adjusting the phase delay of the audio program in a virtually impeccable manner, wherein further steps include self-existing time allocation Every accurate timing signal is received in the network. 10 · —A system for calibrating the phase characteristics of N identical digitized audio program signals distributed by broadcasting studios to N broadcasting stations via N time-division multiplexing (TDM) communication chain, the broadcasting room and the N broadcasting stations each receiving one Accurate timing signals include: N TDM multiplexers in the studio, each of which can multiplex the digitized audio program signals into the studio and ~ N stations Within at least one channel of the established TDM communication chain, and (ii) can multiplex the accurate timing signal received by the studio -20- This paper size applies Chinese National Standard (CNS) A4 specification (210 X 297 mm) 8: 2 / P, 5 > 8 8 8 8 AB c D VI. Patent application scope number Enter another channel of the TDM communication chain For each of the N broadcasting stations, (i) eliminate the TDM demultiplexer from the corresponding one of the N TDM communication chain and the TDM demultiplexer of the studio timing signal, (ii) compare the broadcast A timing signal comparator with a room timing signal and a local timing signal to generate a comparison result, and generating a compensation time corresponding to the comparison result; and (iii) dynamically adjusting the delay of the digitized audio program signal for the compensation One of the effects of time is one of the delay adjustment circuits. -21-This paper size applies to China National Standard (CNS) A4 (210 X 297 mm)