JPH03165643A - Digital data transmission system - Google Patents

Abstract

PURPOSE:To reduce the system cost remarkably and to eliminate the need for the phase adjustment of an incoming data at system installation by allowing all slave stations to use a single radio transmitter-receiver for slave station in common. CONSTITUTION:A slave station radio transmitter-receiver 20 is provided opposite to a master station radio transmitter-receiver 12. Slave station radio line terminators 311-31n of plural slave stations 301-30n process the reception outgoing data from the slave station radio transmitter-receiver 20 through a time slot assigned to itself and transfer the result to a next stage in a way of cascade connection and the output time division multiplex data of the slave radio line terminator 31n of the final stage is sent as the incoming data via the slave station radio transmitter-receiver 20 as the incoming data. Thus, the single slave station radio transmitter-receiver 20 is used by the slave station radio line terminators 311-31n of all the slave stations 301-30n in common to attain the constitution inexpensively and the deterioration in the line quality due to temperature fluctuation or the like is realized and no adjustment at the system adjustment is attained.

Description

[Detailed Description of the Invention] [Overview i] Regarding digital data transmission systems such as high-speed digital leased lines using the Blair Sign time/minute S1 multiple access method by wireless, it is possible to configure a wireless transmitting/receiving device at low cost, and to reduce system installation costs. No adjustment of time? 1. Preventing line quality deterioration due to temperature fluctuations
For the purpose of
1 - A master station, a single wireless transmitter/receiver for a slave station provided opposite to the fishline transmitter/receiver for the master station, and a wireless line termination device and a multiplexer for each slave station as a pair. The slave station is configured such that each of the slave station wireless line termination devices processes the downlink data received from the slave station wireless transmitting/receiving device in its own assigned time slot and transfers the data to the next stage. A plurality of slave stations are connected in cascade, and the output time-division multiplexed data of the last-stage slave station wireless line termination device is transmitted as soil data via the slave station wireless transmitter/receiver. do.

[Industrial application field]

The present invention relates to a digital data transmission system, and more particularly to a digital data transmission system such as a wireless pre-assigned time division multiple access high-speed digital leased line.

A multi-access system in which the line assignment of the digital transmission path is permanent or permanent, and multiple slave stations transmit to a single master station using carrier waves of the same frequency in a time-sharing manner. Time division multiple access (rDMA: r i
ne D 1vision MulHpleACC(4
In the digital data transmission method of 33> method, a single master station and each of the slave stations of the number of stages facing this master station have a wireless transmitter/receiver device, and upstream data transmission from the slave station to the master station is performed in advance. Transmission is performed in bursts at timing phases assigned to each slave station. Therefore, in this digital data transmission process (for the slave station 1), there is multiplexing that controls the transmission data so that they do not overlap.

[Conventional technology]

FIG. 5 shows a configuration diagram of an example of a conventional digital data transmission system. In the figure, 1 is a wireless line termination device for a master station, 2 is a wireless transmitter/receiver f/(TΔ) for a master station, and these constitute a single master station. Moreover, 3A to 3F are wireless transmitting/receiving devices for slave stations (Cho A).

4A to 4F are wireless line termination devices for slave stations, 5△ to 5F are multiplexers, TA3A, wireless line termination device for slave stations 4A, and multiplexer 5A constitute slave station A;
3i, slave station wireless line termination device 41 and multiplexing device 5i
(However, 1 is B.

C2D or E) constitutes T station i. Multiplexer 5
Telephones, facsimile machines, computers, etc. are connected to A to 5E.

In these six conventional systems, the slave stations A to E are slave-synchronized with respect to the master station. In other words, the transmission of data from the master station to the slave stations A to E is performed in a continuous wave as schematically shown by the solid line, and all the slave stations A to F are synchronized with the frame timing phase. FIG. 6 (A>) shows the frame format of this downlink data.

On the other hand, f stations A and -E each transmit upstream data to the master station in a berth 1-shape, as schematically shown by the broken line in FIG. 5, at unique timing phases assigned to themselves. FIGS. 6(B) to 6(F) show the transmission timing of uplink data transmitted from slave stations A to E to the master station. As a result, the master station time-division multiplexes and receives the transmission data from -E to each f station, as schematically shown in FIG. 6(G).

Furthermore, guard pits are provided between adjacent transmission data on the uplink from F8A to F8E to the master station.

In other words, the data received by the master station is time-division multiplexed as shown in Figures 6 (G) and 7 (A), but the adjacent data circled in Figure 7 (A) Since the sources of the data are different, in order to prevent the data from overlapping due to jitter, etc., a few pitches are set in advance as shown in Figure 7 (13).
An empty area (guard bit) is installed. In addition,
FIG. 7(C) shows the bit clock.

Furthermore, in the conventional system, the internal clock is used for handling data such as JJ in the receiving section of the master station, and the structure is such that the data extracted from the received data from slave stations A to E and the L1 clock are not used. .

[Problem to be solved by the invention]

However, the above conventional digital data transmission method is
Adjustment of the uplink data and Q-phase of the slave stations when installing the system is complicated. In other words, for old system equipment, the first III
Connect the setting module to each of the current station and slave stations A to E, and first send the F-algebra 1-pi 1-fixed pattern data from the master station to slave station A, and the colts A to ES that received it Based on the received data, the data is sent back to the master station at a predetermined timing phase.

The master station transmits data indicating the phase difference between each data from the slave stations A to E and the data generated by itself to the f stations A to F.

Then, in F to the slave station, the transmission timing of upstream data is adjusted and transmitted so that the meter pointer of the initial setting module remains at a predetermined scale position. Since this process is repeated to adjust the phase of the uplink data of the slave station, it is complicated to maintain the full phase.

In addition, in the above-mentioned conventional digital data transmission system, the slave stations 3A to 3E and the S line line termination equipment for slave stations M4△ to 4
For example, the data transmission rate between E and E is 16.384Hb/
s, the tolerance for the phase f of the upstream data of T88 and E is small, which is close to the limit of the devices that make up the circuit. Therefore, due to occurrence of temperature fluctuations, etc., the above-mentioned phase shift exceeds the tolerance, often degrading the line quality.

Historically, in the conventional digital data transmission method described above, each of the slave stations A to E is equipped with a wireless transmitter/receiver (rA) 3A to 3A.
3F and the wireless line terminal devices 4A to 4F are provided in pairs, and the wireless transmitting/receiving devices 3A to 3F themselves are expensive, so the cost of the entire system becomes extremely high.

The present invention has been made in view of the above points, so that it is possible to construct a wireless transmitter/receiver at a low cost, and also to eliminate the need for system adjustment and prevent deterioration of line quality due to temperature changes. The purpose is to promote digital data transmission methods.

[Failure to solve the problem]

FIG. 1 shows a basic configuration diagram of the present invention. In the figure, reference numeral 10 denotes a master station, and a four-station wireless line termination device 11 and a master station wireless transmitting/receiving device 12 are placed on the right side. Reference numeral 20 denotes a V-ray transmitting/receiving device for the slave station, which is provided opposite to the neck 12 of the focal-ray transmitting/receiving device for the rA station.

301 to 30 n G, in a plurality of slave stations, each of which has a wireless line t4 for slave stations 31+ to 311 and a multiplexer 321 to
32n in pairs. Wireless line termination device 311 for slave station
~31n processes the received downlink data from the slave station wireless transmitting/receiving device 20 at the time assigned to itself,
They are connected in cascade so as to be transferred to the next stage, and the output time-division multiplexed data from the radio line termination device E 31 n for the slave station at the final stage is transmitted as uplink data via the radio transmitting/receiving device 20 for the slave station.

In this way, in the present invention, a single slave station wireless transmitter/receiver 2
0 to all f stations 30+ to 30n's wireless line terminal device 3
It is unique in that it is shared by TIs 11-31.

(Function) In FIG. 1, the downlink data transmitted from the master station 10 is received by the slave station wireless transmitting/receiving device 20, and then the a-connection data consisting of a plurality of slave station fish line termination devices ¥1311 to 31n. The signal is first input to the slave station radio line termination device 311 at the first stage of the connection circuit. The format of this human-powered r datater is shown in Figure 2.
As shown in A>, following control information consisting of room synchronized transmission, etc., slave stations 30+ to 30 are sent to each of n time slots.
The format is that the downlink data a1 to a71 for 1 is h-division multiplexed.

The radio line termination device 311 in the FIA 30+ mentioned above takes in the uplink data a1 multiplexed in the first time slot immediately after the 11 control information assigned to itself from among this input uplink data, and furthermore takes in the downlink data that it has created by itself. b1 is placed in its own time slot y, and the data formatted as shown in FIG. 2(B) is transferred to the radio line termination device 312 in the next station f 30z.

The wireless line terminal device 312 takes in the uplink data a2 of the time slot assigned to itself from this input data, and multiplexes the downlink data b2 that it has generated itself into the time slot, as shown in FIG. 2(C). The data from Noornts 1- is stored in the next slave station 301! ! ! , the line is transferred to the line terminal equipment 3.

From then on, in the same manner as above, the wireless line termination device 313 is connected to the wireless line termination equipment 314 in the child rJ304 at the next stage.
The data of No. 4-mat as shown in Figure (D) is transferred,
] - As shown in FIG. 2 (E), each data of the n time slots immediately after the control information is transferred sequentially from the radio line termination device 31n in the final slave station 30n as uplink data. The time division multiplexed data replaced by b1 to bn is extracted. This time-division multiplexed data is transmitted to one slave station 10 as uplink data via the slave station radio transmitter/receiver 20.

In this way, according to the present invention, all slave stations 301 to 3
01 can share the slave station wireless transmitter/receiver 20 of A-.

Further, by configuring the master station 10 to include a room synchronization circuit in the same way as the slave stations 301 to 30n, it is possible to maintain the uplink and downlink frame timings of the wireless section.

〔Example〕

FIG. 3 shows a construction diagram of an embodiment of the present invention. This example (
In the example of f8 number n=5, 1. is added to the same components as in FIG. U
Lung] - What is No. n? In FIG. 3, the master station 10
(The main station wireless line termination unit 11 and the main station wireless transmitting/receiving device (R A: TranSIlitter) are used to transmit continuous wave downlink data, which is similar to the conventional DM method for high-speed digital data transmission. The system is the same as the TDMA system, but unlike the conventional TDMA system, it uses Sato communication (SCPC: Sir+
Similar to the gleChannCI Per Carrier) system, the wireless line termination equipment 271 of vA7I'1310
1 is also provided with a frame synchronization circuit.

In addition, the radio transmitting/receiving devices for slave stations (5 units of f station wireless line connection devices 311 to 315 such as 20) are connected in cascade via a coaxial cable 36 in a loop.M line line for f0 Among the terminal devices 311 to 31s, the distance between adjacent f-station high-wire 1-tansen hiiragi devices is several hundred mf'1 degree.

Furthermore, the multiplexing devices 321 to 325 in the slave stations have telephone If
f (rEL)33. Facsimile machine (FAX)
34. A computer (CPU) 35 is appropriately connected. TΔ20 on the slave station side of this embodiment is characterized in that uplink data is transmitted in a continuous wave instead of a burst wave.

This embodiment with such a configuration is mostly used in urban areas and within cities like the conventional wireless RDMA high-speed digital leased line, but its application range is much wider than the several kilometers of the conventional system due to the use of coaxial cables 36, etc. It is not wide, and 2 to 4 systems are allocated within one system of the conventional system. One MA of the system of this embodiment may be constructed in a high-rise building.

Next, a wireless line termination device 311 for a slave station, which is the main part of the present invention.
The configuration of 315 and iEH will be explained in more detail. The slave station radio line termination devices 311 to 315 each have the same configuration, as shown in FIG. 4. In the figure, an input terminal 41 receives the F data from TΔ20 or the wireless line termination device for the slave station at the previous stage. This input data is, for example, CM I (Coded tvlark,
1 nversion) code, "1" (inverted every 41 pits, "O" is 1 bit cycle! The first Y of the month has a high level and the second half has a waveform of a low level.

The input data of input Fi1 is input to amplifier 42. Frame opening circuit 439 separation device 44. The data is input to a downstream data processing circuit consisting of a speed conversion circuit 45, a 7-block 46, and a downstream timing generator 47.

The tri-timing generator 47 emits various timing pulses to the frame synchronization circuit 431 and the separation device d44 and σ.
A necessary timing pulse is supplied to the speed hemp conversion circuit 45.

The above human data is amplified to a desired level by a seventh amplifier 42, then room synchronized by a frame synchronization circuit 43 based on the room synchronization circuit in the data, and then supplied to a separation device 44. , here, only the data of the self-assigned time slot is separated and extracted. This separated and extracted data is, for example, 16.384t4b/s, and the speed conversion circuit 45 converts it into 192b/S~6Hb/S1? ? After being converted to a transmission rate of 90 degrees, it is amplified by the /sive 46 and then sent to the multiplexer in the same slave station via the output terminal 48. Uplink data from the multiplexer is input. Input E 'J' 4
The human power of 9 is 7 lbs.50. Room Domei circuit 51
, speed conversion circuit 52. Frame 7 liner 53° multiplexer 54. The uplink data is input to an uplink data withdrawal circuit consisting of an amplifier 55 and an uplink timing generator 56. The multiple timing generator 56 generates various timing pulses, and the frame synchronization circuit 51 . Hayamaro conversion circuit 52. Frame Alaino 53. The necessary timing pulses are supplied to the multiplexer 54 and the like.

The input upstream data at the input terminal F49 is amplified to the required level by the amplifier 50, then frame synchronized by the room synchronization circuit 51, and the transmission rate is changed to 16.384 by the speed conversion circuit 52.
After being converted into Hb/s, it is supplied to the frame aligner 53. Frame aligner 53 < Yo-room synchronization circuit 43
Received upstream data and frame synchronization data extracted from f5
This is a delay circuit for room synchronization (phase) with the output upstream data of No. 3, and outputs upstream data for one time throttle at the timing of the time slot assigned to this slave station.

The multiplexing device 54 converts one slot from the room aligner 53 into one slot.
- time division multiplexing of the L redata and the data from the room synchronization circuit 43, and as explained in conjunction with FIG. Only the upstream data from the room 7 liner 53 is replaced, and each data of the other time slots generates a multi-thousand divided data consisting of the same data as the manual data of the input terminal J-41, and this is amplified. 55 and output terminal F57 to the next stage f-station radio line termination device or T△
Transfer to 20.

According to the present embodiment, the downlink data received at 'rA 20 is sent to the slave station radio line termination devices 311 to 3 in each slave station.
15, the upstream data of each time slot l~ is taken out in turn from the M-line circuit F2 Hiiragizui device 315 for F station in the final stage! , :h minute υ1 multiplexed uplink data is converted into radio waves of 0 frequency by the digital A20 and transmitted as Δ.

Therefore, according to this embodiment, since it is a slave station, "A20
Since this method is simple, the system cost can be significantly reduced compared to the conventional method. Furthermore, since the uplink data input to the TA 20 has already been time-division multiplexed, it is transmitted in continuous waves instead of in burst waves as in the conventional system. Therefore, guard pits, which were conventionally necessary, can be eliminated, and phase adjustment between data can be eliminated. Furthermore, since room synchronization is performed on the upstream data at the master station, there is no need to adjust the phase of the upstream data at the slave station when the system is set up, and phase shifts in the upstream data occur before temperature changes. b There is no deterioration in line quality at all! -You can take enough gin. Historically, the system is easy to install and recover, and the data transmission speed of this embodiment is 16,384 Mb/s, the same as the conventional DMA system, so the data transmission speed is 8 Hb/s. The existing 5cpc which is
The transmission capacity is faster than the high-speed digital data transmission method.

It should be noted that the present invention is not limited to the above-described embodiment, and it is also possible in principle to transmit data between each f station using the coaxial cable 36 and using f% radio.

[Effects of the Invention +8] As described above, according to the present invention, all the slave stations can share the slave station wireless transmitter/receiver of A-, so the system cost can be significantly reduced compared to the conventional system. is possible,
In addition, by installing a frame synchronization circuit in the master station, it is possible to independently control the frame timing for uplink and downlink in the wireless section, so there is no need to adjust the phase of uplink data when the system is set up. 1) It is possible to eliminate deterioration in line quality due to a phase shift in signal data that occurs before temperature fluctuations.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the original drum of the present invention, Fig. 2 is a timer for explaining the operation of Fig. 1, Fig. 3 is a block diagram of an embodiment of the present invention, and Fig. 4 is a block diagram of an embodiment of the present invention. Block diagram, Figure 5 1. L
FIG. 6 is a block diagram of the conventional system, and FIG. 6 is a diagram for explaining the operation of FIG. 5. FIG. 7 is a diagram for explaining the guard hit. In the figure, 10G, 1L11Q station, 11 is a wireless line termination device for JLL slave station, 12 is a wireless transmitter/receiver for a master station (TΔ), and 20 is a wireless transmitter/receiver for a slave station (
A), 30+ to 301 are slave stations, 311 to 3111. t″Slave station wireless line termination device, 32
+~321 indicates the multiplexing 5A position.

Claims (2)

[Claims] (1) A single master station (10) having a base station wireless line termination device (11) and a base station wireless transmitter/receiver (12), and a base station installed opposite to the base station wireless transmitter/receiver (12). A single radio transmitting/receiving device (20) for a slave station, each having a pair of radio line termination devices (31_1 to 31_n) and a multiplexing device (32_1 to 32_n) for the slave station, and a wireless transmitting/receiving device for the slave station. The slave station radio is configured so that each of the slave station wireless line termination devices (32_1 to 32_n) processes the received downlink data from the device (20) in its own assigned time slot and transfers the data to the next stage. Line termination equipment (32_1 to 32
A plurality of slave stations (_n) are cascade-connected and transmit the output time-division multiplexed data of the last-stage slave station wireless line termination device (32_n) as uplink data via the slave station wireless transmitter/receiver (20). 30_1 to 30_n). (2) The master station (10) and the plurality of slave stations (30_1 to
3. The digital data transmission system according to claim 1, wherein the digital data transmission system 30_n) each have a separate frame synchronization circuit.