JPS6118892B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a service tone sending system using multiple networks. Conventionally, when transmitting service tones in an electronic exchange, a common group of generators (Ge ₁ ) 1'a to (Gen) 1'n are used as shown in FIG.
For the receiver (R ₁
It was necessary to avoid interference between 3'a to (Rn)3'n. In addition, technology for sending out various signal tones or service information on time-division multiplexed paths and distributing them to subscribers (Japanese Unexamined Patent Publication No. 51-3516;
151005), but it also has the drawbacks of poor service and poor cost efficiency. This is unavoidable when using conventional space division, but in reality, service deteriorates when connection demand exceeds expectations, and there are many areas that are not normally used, making it inefficient in terms of cost. The present invention has been made in order to solve such conventional difficulties, and when transmitting service tone signals generated from a service tone generator to a plurality of subscribers, address data of the service tone generator and a plurality of service tone signals are transmitted to a plurality of subscribers. The address data of the subscriber is stored in two different storage devices in correspondence with each other, and the reset data is stored in one of the storage devices, and these address data are stored at a predetermined time. The service tone generator modulating circuit and the subscriber demodulating circuit corresponding to the respective read address data are decoded to correspond to the read time. The reset data is sent as a sampling pulse, and after reading out all of the address data, the reset data is read out, and the address data stored in the storage device is repeatedly and sequentially read out every time the reset data is read out. The service tone sending system makes it possible to provide sufficient service without using any sending buffers. The method of the present invention will be described below with reference to the drawings, with reference to an embodiment in which the method is applied to a time division PAM multiplexing method for transmitting service tone signals generated from a service tone generator to a plurality of subscribers. In FIG. 2, storage devices (RAM-T) 1 and (RAM-R) 2 each consist of readable and writable IC memories;
T1 is a service tone generator Ge ₁ ......Gen, 14a that generates service tones such as dial tone, ringing tone, and busy tone.
......14n and subscriber 13a......13n's transmitting side address data, RAM-R2 stores subscriber 1's address data.
Address data of the receiving side of 3a...13n is stored respectively. The clock counter (CK.COUNT) 3 is a register that counts clock pulses, and each time it counts, it sends a BCD code to the RAM-T1.
and specify the address to be read to RAM-R2,
RAM-T1 or as in the illustrated embodiment
When the data read from RAM-R2 is reset data, it is reset and the count is repeated again. Clock CKG4 provides clock pulses to CK.COUNT3, and RAM-T1 and
It also performs decoding control of the output decoder (described later) of RAM-R2. Tri-state buffer TBS-15 that does not interfere with each other
TSB-2 6 sets the write address Da when writing address data to RAM-T1 and RAM-R2.
It has a function to replace the read address by CK.COUNT3. Reset circuit RESETDEC7
If the output data of RAM-T1 or RAM-R2 as in the illustrated embodiment is reset data, it detects this and resets CK.COUNT3. Decoder (TO DEC) 3
and RO DEC9 are RAM-T1 and RAM- respectively.
The output data of R2 is decoded and sampling synchronization pulses for transmission and reception are applied to the time division multiplexed path by PAM. Control unit (CONTROL) 10
is a signal requesting external writing or rewriting of RAM-T1 and RAM-R2, i.e.
RAM-T1, RAM-R2, TSB-1 5 and TSB-2 6 are controlled each time by signals of TS specifying RAM-T1, RS specifying RAM-R2, and MW requesting writing, and at the same time CK .It has a function to reset COUNT3. That is, CONTROL 10 opens TSB-1 5 unless a signal is given to RS or TS;
Close TSB-2 6 and RAM-T1 and RAM
- Put R2 into read mode. Also, when a signal is given to RS or TS, TSB-1
5 is closed, TSB-5 6 is opened, and if a write signal is given to MW, RAM-R2 is written when a signal is given to RS, and RAM-R2 is written when a signal is given to TS. - Switch T1 to the write mode and write the address data given by Ad to the address designated by Da at that time. Note that while a signal is being applied to TS or RS, CK.COUNT3 is reset. The time division multiplex path 12 has subscribers 13a...1
3n is a PAM modulation/demodulation unit MDM1 11a each including a PAM modulation circuit and a PAM demodulation circuit.
It is connected via MDMn11n. In addition, the PAM modem units MDM1 11a to MDMn
11n respectively send and receive PAM pulse signals to time division multiplexing path 12 via the outputs of TO DEC 8 and RO DEC 9. In addition, the decoder
The lines running from TODEC to the demodulation circuits MDM1 to MDMn are used when multiplexing speech, but since they are not directly related to the present invention, their explanation will be omitted. In addition, service tone generators Ge ₁ 14a...Gen 14n are connected to the time division multiplex path, respectively.
PAM modulation section M ₁ 15a including PAM modulation circuit...
connected via Mn15n, and each modulation section is TO
PAM is sent to time division multiplexing path 12 by the output of DEC8.
Sends out a pulse signal. Next, in the device as described above, the service tone generator Ge ₁ 14a to the subscriber 13a
to another service tone generator Ge ₂ 14b
The operation when sending service tones from one subscriber to another subscriber 13b will be explained. In this case, first, RAM-T1
The address data (0001) of the service tone generator Ge ₁ is written to address 0 of RAM-R2, the address data (0010) of subscriber 13a is written to address 0 of RAM-R2, and then the service tone generator Ge 1 is written to address 1 of RAM-T1. Tone generator Ge ₂ address data (0011)
However, the address data (0100) of subscriber 13b is written in correspondence with address 1 of RAM-R2, and finally
Reset data (1111) at address 2 of RAM-R2
is written.

[Table] Is writing to RAM-T1?
This is done by specifying whether to write to RAM-R2 using TS or RS, setting the above address to Da, and applying a write signal to MW. After writing or rewriting the predetermined address data in RAM-T1 and RAM-R2 in this way, TS and
If you remove the RS signal, by CK.COUNT3,
The written address data is sequentially read out, and the data is decoded by TO DEC8 and RO DEC9, and the PAM modulation circuit and PAM modulation/demodulation section of PAM modulation unit M ₁ 15a corresponding to the address data are decoded by TO DEC8 and RO DEC9.
A sampling synchronization pulse is applied to the PAM demodulation circuit of the MDM1 11a, and similarly to the PAM modulation circuit of the PAM modulation section M2 15b and the PAM demodulation circuit of the PAM modulation/demodulation section MDM2 11b. The operating state at this time is shown in FIG. That is, when writing is completed and there is no signal on TS and RS, RAM-T1 and RAM-R2 go into read mode, and TSB-15 is opened.
TSB-2 6 is closed and at the same time CK.
COUNT3 changes from the reset state to the counting state and starts counting the clock pulses of CKG4 from 0. Therefore, when the output of CK.COUNT3 is (0000), RAM-T1 and RAM-R2
Address data (0001) stored at address 0 of
(0010) at predetermined times, open the transmission gate of the PAM modulator M1 15a using TO DEC8 and RO DEC9, and send out the PAM pulse signal to the time division multiplex path 12.
The reception gate of the PAM modulation/demodulation section MDM1 11a is opened to take in the PAM pulse signal of the service tone sent out by the PAM modulation section M1. That is, the PAM modulation section of the service tone generator Ge ₁ corresponding to the read address data (0001) and (0010), respectively.
PAM modulation circuit of M1 15a and subscriber 13a
By sending each of the read address data as a PAM sampling pulse corresponding to the read time to the PAM demodulation circuit of the PAM modulation/demodulation unit MDM1 11a of the PAM modulation unit M1,
A sample signal of one service tone is transmitted to the PAM modulator/demodulator MDM1. In this way,
The count of CK.COUNT3 advances and the output becomes (0001)
When , the address data (0011), (0100) stored at address 1 of RAM-T1 and RAM-R2
is read out, and a sample signal of one service tone is then transmitted from M2 to MDM2. When the reset data (1111) stored in address 2 of RAM-R2 is read out in this way,
RESETDEC7 detects this and CK.COUNT3
Reset. After that, CK.COUNT3 starts counting again from 0 and repeats this operation. In this way, newly RAM-T1 and RAM
- PAM modulation unit M1......Mn 15a...... until the contents of -R2 are written or rewritten.
15n PAM modulation circuit and PAM modulation/demodulation section
MDM1……MDMn 11a……11n
Controls the PAM demodulation circuit and configures the network. The operating state at this time is shown in FIG. Note that even when rewriting is performed, the reset data is written at the end of the valid data. Here, the memory size (m) of RAM-T1 and RAM-R2 is the total number of channels in the network of this system (however, one channel in one direction). In addition, in the above example, the address data is expressed in 4 bits per word, but generally, the address data is expressed in the PAM modulator 15a.
......15n and PAM modem section 11a...1
If the total number of 1n is n, the number of bits equal to n' is required from the equation n=2 ⁿ '. That is, in this case, the configuration of CK.COUNT3 should be a minimum m-adic counter, and the word length of the first address of RAM-T1 and RAM-R2 should be n' bits. Here, for the configuration of TSB-15 and TSB-26, m' bits may be prepared so that m=2 ^m '. Further, the RESETDEC 7 may be configured for n' bits, and the capacity of TODEC 8 and RODEC 9 may also be configured for n' bits and n out. Therefore
It is also necessary to give m' bits and n' bits to Da and Ad, respectively. Here, the clock frequency ck required for CKG4 is
is expressed as ck=2s·m. m is the total number of channels mentioned above, s
is the highest frequency of the transmission band, and 2 is a coefficient according to the sampling theorem. Also, the number of channels to ensure demodulation of s is mch
Then, ck=2s・mch is sufficient, and as the number of channels used increases, one PAM modem unit MDM11 or one PAM modem unit MDM11 or
The sampling frequency given to the PAM modulator M15 decreases, and if it exceeds mch, s is no longer guaranteed. For example, if the total number of PAM modulators MDM11 and PAM modulators M15 is 16, the total number of channels is 8, the number of effective channels is 4, and the transmission band is 8KHz, then CK.COUNT......octal counters TSB-1, TSB- 2...3 bits RAM-T, RAM-R...8 x 4 bits RESETDEC...4 bits TODEC, RODEC...4 bits, 16 outs. Also, the required ck at this time is ck = 2 x 8 (KHz) x 4 = 64 (KHz), which means that it is sufficient to set it to 64KHz. Next, regarding external writing and rewriting control, that is, control of Da, Ad, TS, RS, and MW, during this period, the sending of sampling synchronization pulses to the PAM modulator/demodulator MDM11 and the PAM modulator M15 is stopped. Therefore, it is necessary to process this within a time period that does not actually pose a problem. Considering this point, Da, Ad,
The TS, RS, and MW may be controlled manually, but in the case of this method, means using a processor and computer are effective. Note that in the above explanation, the present invention will be explained using time division multiplexing.
Although an example in which the present invention is applied to a PAM service tone transmission method has been described, it can also be applied to the same method using PCM and PWM. As is clear from the above description, according to the system of the present invention, the address data of the service tone generators 14a to 14n and the address data of the plurality of subscribers 13a to 13n are stored in the storage devices 1 and 2 divided into two. Write and rewrite in correspondence with address data,
By erasing the data, a network for transmitting service tones can be easily configured, that is, the storage devices 1 and 2 can be controlled as if they were the network itself. In addition, synchronization of sampling pulses for sending out service tones is achieved by making the addresses of storage devices 1 and 2 correspond, and can be synchronized using software. At this time, reset data can be used to adjust the demodulation quality in response to increases and decreases in connection demand. It is possible to flexibly deal with this and achieve highly efficient services with zero time loss. Therefore, when transmitting service tones, there is no need for a conventional transmission buffer, and there is no need to specify the number of channels or set the pulse train, making it possible to easily configure a network. Since we have adopted a service tone transmission method by dividing, it is possible to always provide 100% service for traffic, and there is no need for buffering, and only one service tone generator is required for one type of service tone. It is also very cost effective since it only requires a generator.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the connection relationship between a service tone generator and a receiver in conventional service tone transmission, FIG. 2 is a block diagram showing an embodiment of the present invention, and FIGS. 3 and 4. are respectively,
FIG. 3 is an explanatory diagram showing the operation of each signal in writing and reading. 1, 2...Storage device, 11a...11n...
A PAM modulation/demodulation section including a PAM modulation circuit and a PAM demodulation circuit of a subscriber, 13a...13n...Subscriber, 14a...14n...Service tone generator, 15a...15n...Service tone generator PAM modulation section including PAM modulation circuit.

Claims (1)

[Claims] 1. When transmitting the service tone signal generated from the service tone generator to multiple subscribers, the address data of the service tone generator and the address data of the multiple subscribers are made to correspond and divided into two. The reset data is stored in different sections of the storage device, and the reset data is stored in one of the storage devices, and these address data are sequentially read out at predetermined times, and the reset data is stored in different sections of the storage device. The read address data is decoded and sent to the modulation circuit of the service tone generator and the demodulation circuit of the subscriber as a sampling pulse corresponding to the read time, and after all the address data has been read, A service tone sending system using multiple networks, characterized in that reset data is read and address data stored in the storage device is repeatedly and sequentially read each time the reset data is read.