JPH0352697B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technique of the Invention] The present invention relates to an auxiliary signal insertion/separation method, and in particular,
An auxiliary signal insertion/separation method that is effective in transmitting/receiving equipment in which the analog signal processing section and the digital signal processing section are arranged separately and independently at the top of the tower and above the ground, such as in an intermediate relay station installed on a steel tower, for example. Regarding.

[Technology background]

In general, transmitting/receiving devices employ an auxiliary signal insertion/separation method in which an auxiliary signal for maintenance, monitoring, etc. is inserted into a main signal and transmitted, and the auxiliary signal is separated and extracted on the receiving side.

A conceptual system configuration diagram of the auxiliary signal insertion/separation method is shown in FIG. In Figure 1, T/R is a transmitter/receiver, SC auxiliary signal insertion/separation circuit, OW and SV
are auxiliary signals called order wire and supervisory control signals, respectively. The transmission auxiliary signal input to the SC is inserted into the transmission main signal at the T/R by the operation of the SC, and a transmission signal that is a combination of the main signal and the auxiliary signal is emitted from the antenna. On the receiving side, the auxiliary signal is separated from the main signal at the T/R by the operation of the SC, received by the SC, and sent from the SC.
An auxiliary signal such as OW or SV is output.

In such an auxiliary signal insertion/separation method, when the main signal is modulated with a digital signal, such as PSK modulation, and the main signal is modulated with a digital signal, such as in an intermediate relay station installed on a steel tower, When using a transmitting/receiving device in which the signal processing sections are arranged separately and independently, such as an analog signal processing section installed at the bottom of a steel tower and a digital signal processing section installed at the bottom of a steel tower, it is not possible to send and receive auxiliary signals in either signal processing section. must not. For example, this is because a maintenance person at the top of the tower and a maintenance person at the bottom of the tower need to perform maintenance, monitoring, etc. by mutually transmitting and receiving auxiliary signals. Similarly, when transmitting and receiving auxiliary signals between relay stations or between terminal stations and relay stations, it is necessary to be able to transmit and receive auxiliary signals both at the top and bottom of the tower. In this case, there is a need for a simple and inexpensive method for inserting and separating the auxiliary signals in the analog signal processing section and the digital signal processing section.

[Prior art and problems]

FIG. 2 is a block diagram showing an example of a conventional auxiliary signal insertion/separation system. The method shown in FIG. 2 is an analog signal processing method that is well known as a composite modulation method.
The PCM signal is modulated, for example, by PSK, FSK, etc., using a carrier wave output from the local oscillator 2, and the carrier wave itself is FM-modulated by analog auxiliary signals such as OW, SV, etc. On the receiving side,
The demodulator 3 separates and outputs the analog auxiliary signal and the digital signal which is the main signal. As described above, according to the composite modulation method, the insertion and separation of auxiliary signals is performed only in an analog manner, and there is no digital signal processing section, so it can be realized relatively easily.

FIG. 3 is a conceptual system configuration diagram when inserting and separating auxiliary signals digitally. The difference between FIG. 3 and FIG. 2 is that on the transmitting side, the oscillation frequency of the local oscillator 20 is controlled by the auxiliary signal.
It is not FM modulated and is fixed, and is provided with a synchronization insertion circuit (SI) 4 for inserting a digital auxiliary signal after establishing synchronization of the transmitting digital signal, and on the receiving side, Synchronous separation circuit (SS) for extracting digital auxiliary signals during the auxiliary signal time period after establishing synchronization of the main signals of
5 is provided. The digital auxiliary signal for transmission is obtained by digitally converting the analog auxiliary signal using a delta modulator (not shown) or the like. The received digital auxiliary signal may be converted into an analog signal and received by a delta demodulator or the like (not shown).

On the transmitting side, the part _A1 enclosed by the dotted line that includes the modulator 1 and the local oscillator 20 is the analog signal processing section, and the part enclosed by the dotted line that includes the synchronization insertion circuit 4
_D1 is a digital signal processing section. On the receiving side,
The part surrounded by a dotted line including the demodulator 3 is an analog signal processing section A ₂ , and the part surrounded by a dotted line including the synchronization separation circuit 5 is a digital signal processing section D ₂ .

At relay stations, etc., the digital signal processing unit
D ₁ and D ₂ are analog signal processing units A _{1 and} D 2 at the bottom of the steel tower.
A ₂ is often installed at the top of a steel tower. This is shown in FIG.

FIG. 4 is a schematic side view showing the arrangement position of the transmitting/receiving device provided on the steel tower. In Figure 4, 1
0 is a station building such as an intermediate relay station installed on the ground, 11
is a steel tower installed on the roof of the station building 10, 12 is an antenna installed on the top of the steel tower, A is an analog signal processing section of a transmitting/receiving device placed at the top of the steel tower, and D is an analog signal processing unit placed inside the station building 10. This is the digital signal processing section of the transmitting/receiving device. The analog signal processing section A includes an RF section, an IF section, and modulation/demodulation sections 1 and 3 (FIG. 3) of the transmitting/receiving device. The digital signal processing section D includes a synchronization separation circuit 5 and a synchronization insertion circuit 4 (FIG. 3).

As shown in FIG. 4, in a transmitting/receiving device in which the analog signal processing section A and the digital signal processing section D are arranged separately, when attempting to digitally insert and separate auxiliary signals as shown in FIG. 3, the digital signal Insertion and separation of auxiliary signals in the processing section can be performed without any problem as explained with reference to Fig. 3, but the maintenance personnel near the analog signal processing section are not the same as the maintenance personnel near the digital signal processing section _D1 at the bottom of the tower. Even if an attempt is made to communicate using an auxiliary signal, it is not easy to do so, unlike the composite modulation method shown in FIG. Furthermore, it is not easy for a maintenance person of an analog signal processing section at the top of a steel tower to transmit and receive auxiliary signals with a maintenance person of an analog signal processing section or a digital signal processing section of another station.

Conventionally, when an attempt is made to insert and separate an auxiliary signal in an analog signal processing section, there is a problem in that a synchronization circuit or the like is also required within the analog processing section, which increases the cost of the device.

Conventionally, when a synchronization circuit is not provided in the analog processing circuit, the transmission auxiliary signal input to the analog signal processing section A is once returned to the synchronization insertion circuit in the digital signal processing section D to be synchronized with the transmission digital signal. After the insertion, the analog signal processing section A
Furthermore, the signal received by the analog signal processing unit A is also returned to the digital signal processing unit D, where the main reception signal and the reception auxiliary signal are separated by the synchronization separation circuit 5. It is necessary to return the separated reception auxiliary signal to the analog signal processing section A again and receive it. In this case, in addition to the existing line existing between the analog signal processing unit A and the digital signal processing unit D, if an additional line for sending and receiving auxiliary signals for transmission and reception is provided, the insertion and separation of the auxiliary signals can be performed. Although it is possible to perform this digitally in the analog signal processing section, adding a line complicates the wiring work and raises the price of the transmitting/receiving device.

[Purpose of the invention]

In view of the above-mentioned problems, an object of the present invention is to provide a transmitting/receiving device in which an analog signal processing section and a digital signal processing section are arranged separately and independently, in which an auxiliary signal for transmission to another station is transmitted to a self-contained system within the analog signal processing section. After passing through the digital signal processing section via the station reception section, it is sent from the own station transmission section in the analog signal processing section, and the auxiliary signal for reception from other stations is separated and extracted in the digital signal processing section. , based on the concept of demodulating signals in the own transmitting section within the analog signal processing section, it is possible to easily and inexpensively transmit analog signals without adding an auxiliary signal transmission line between the analog signal processing section and the digital signal processing section. An object of the present invention is to provide an auxiliary signal insertion/separation method that can digitally insert an auxiliary signal into a main signal in a signal processing section and can digitally separate the auxiliary signal from the main signal.

[Structure of the Invention] In order to achieve the above object, the present invention provides a receiving section having a demodulating section that demodulates a received signal obtained by combining an auxiliary signal for maintenance management and a main signal; an analog signal processing section comprising a transmitting section having a modulation section that modulates an auxiliary signal and a main signal for the a first synchronization section that decodes the demodulated reception signal from the demodulation section to obtain a reception digital signal; and a first synchronization section that decodes the demodulated reception signal from the demodulation section and encodes the transmission digital signal to the modulation section. The analog auxiliary signal for transmission to be transmitted from the analog signal processing section to another station or the digital signal processing section is synthesized with the analog demodulated reception signal from the demodulation section. , the first synchronization section in the digital signal processing section extracts the demodulated received signal in an analog manner and receives it in the digital signal processing section, or the analog extracted auxiliary signal is converted into a digital signal. The auxiliary signal for reception in the analog signal processing section is synthesized with a digital signal for transmission by the second synchronization section and transmitted to another station via the modulation section. The first synchronizing section synchronously separates the digital auxiliary signal from the main signal of the received signal, converts the synchronously separated digital auxiliary signal into an analog signal, and then converts the digital auxiliary signal into an analog signal from the transmitting digital signal by the second synchronizing section. This is an auxiliary signal insertion/separation method characterized in that the analog signal processing unit receives the received signal by demodulating the combined transmission signal after combining the two signals.

[Embodiments of the invention]

Embodiments of the present invention will be described in detail below with reference to FIG. 5 and subsequent figures.

FIG. 5 is a system configuration diagram schematically showing an embodiment of the present invention. In FIG. 5, one transmitting/receiving device TR is assumed to be the transmitting side, and the other transmitting/receiving device RV is assumed to be the receiving side. Transmitting side TR is analog signal processing section
A ₁₀ and a digital signal processing section D ₁₀ , and the receiving side RV also consists of an analog signal processing section A ₂₀ and a digital signal processing section D ₂₀ .

Both analog signal processing units A ₁₀ and A ₂₀ include a receiving unit R and a transmitting unit T.

Analog signal processing unit A ₁₀ converts the auxiliary signal SC to digital signal processing unit D ₁₀ or transmitting/receiving device RV.
When attempting to transmit the auxiliary signal to the main signal in the transmitter T, it is impossible to insert the auxiliary signal into the main signal because it cannot be synchronized with the main signal. Accordingly, in the present invention, the auxiliary transmission signal SC is input to the receiving section R, combined with the received signal, and delivered to the digital signal processing section _D10 . Digital signal processing section D ₁₀
In this case, the digital auxiliary signal is synchronously separated from the received signal and received, or after synchronously separated,
After establishing synchronization of the digital signal for transmission, for example, the PCM signal, the auxiliary signal for transmission is transmitted during the auxiliary signal time period.
Insert SC into the transmitting digital signal and send to the transmitter T.
Output from the antenna via.

On the other hand, when attempting to receive the auxiliary signal SC in the analog signal processing unit A ₂₀ of the receiving side RV,
This is impossible because the main signal cannot be synchronized from the receiving section R. In the present invention, after inputting the received signal from the receiving section R to the digital signal processing section D ₂₀ , the reception signal is input to the digital signal processing section D ₂₀ . The main signal and the reception auxiliary signal are synchronously separated and received as a digital auxiliary signal, or they are synchronously separated, and then the reception auxiliary signal is synchronously inserted into the transmission digital signal from the receiving side RV, and the reception analog auxiliary signal is sent to the transmitter T. demodulated and received.

In this way, it becomes possible to transmit and receive the auxiliary signal in the analog signal processing unit without providing any new wiring for the auxiliary signal.

FIG. 6 is a block diagram showing the transmitting side TR shown in FIG. 5 in more detail. In FIG. 6, the transmitter T includes a transmit signal modulator (M) 10, a hybrid circuit (H ₁ ) 11, and a receive auxiliary signal demodulator (DEM) 12, and the receiver R includes a It includes a received signal demodulator (DEM) 13, a hybrid circuit (H ₂ ) 14, and a transmission auxiliary signal modulator (MOD) 15. The transmitting section T and the receiving section R constitute an analog signal processing section _A10 .
Digital signal processing section _D10 is a synchronous separation circuit (SS)
16, a synchronous insertion circuit (SI) 17, and a digital auxiliary signal insertion/separation circuit (DS) 18.

When transmitting the analog auxiliary signal SC(A)IN from the analog signal processing unit A ₁₀ to the receiving side RV, it is necessary to send the analog auxiliary signal SC(A)IN to the upper or lower frequency band ( The analog auxiliary signal is modulated by the modulator 15 so that the frequency band of the auxiliary signal exists in the frequency band of the auxiliary signal (see Figure 7 a or b), and the hybrid circuit 14 synthesizes the main signal and the modulated auxiliary signal. A frequency signal or baseband signal is obtained and sent to the digital signal processing section _D10 . In the digital signal processing section _D10 , a synchronization separation circuit 16 digitally separates the main signal and the auxiliary signal. The separated digital main signal is the received digital signal PCM
Received as OUT. The other separated digital auxiliary signal is inserted into the auxiliary signal time period by the synchronization insertion circuit 17 after establishing synchronization with the transmission digital signal PCM IN. Synchronous insertion circuit 17
The output is input to the modulator 10 as an intermediate frequency signal or baseband signal via the hybrid circuit (H ₁ ) 11 in the analog signal processing section A ₁₀ . The modulator 10 modulates an input analog signal including a main signal and an auxiliary signal using a local oscillation circuit not shown in FIG. 6, and transmits the modulated signal from a transmitting antenna TA.
In this way, the analog auxiliary signal SC(A)IN inputted to the receiving section R is digitally inserted into the transmitting main signal in the digital signal processing section _D10 , and then sent to the transmitting antenna.
Sent from TA.

When the auxiliary signal is received by the analog signal processing section A ₁₀ , the auxiliary signal is received via the receiving antenna RA, the demodulator 13, the hybrid circuit 14, the synchronous separation circuit 16, the synchronous insertion circuit 17, the hybrid circuit 11, and the auxiliary signal demodulator 12. Analog auxiliary signal SC(A)
OUT is received.

Of course, by using the digital auxiliary signal insertion/separation circuit 18, it is also possible to transmit and receive the digital auxiliary signal SC(D).

It is also possible to exchange auxiliary signals between analog signal processing section A ₁₀ and digital signal processing section D ₁₀ within the same station. That is, modulator 15
The analog auxiliary signal SC(A)IN input to the digital auxiliary signal insertion/separation circuit 18 can be received as a digital auxiliary signal, and conversely, the analog auxiliary signal SC(A)IN input to the digital auxiliary signal insertion/separation circuit 18 can be received as a digital auxiliary signal. )IN is received at the output of the demodulator 12 as an analog auxiliary signal SC(A)OUT.

FIG. 7 is a diagram for explaining a state in which the auxiliary signal is superimposed on the main signal in the hybrid circuit 14 of FIG. 6. FIG. 7a shows a case where the frequency band of the auxiliary signal SC is set above the frequency band of the main signal D and is superimposed thereon. FIG. 7b shows a case where the main signal D has a highly effective scrambler and has no or little DC component, and the auxiliary signal SC is superimposed with a DC component.

Figure 8 shows the digital signal processing section shown in Figure 6.
FIG. 3 is a block diagram showing _D10 in more detail. In FIG. 8, 20, 22, 24 and 27 are hybrid circuits, 21 is an auxiliary signal demodulator, 23 is an auxiliary signal modulator, 26 is a delta modulator, 28 is a delta modulator, and 25 and 29 are respectively It is a synchronous circuit.

The intermediate frequency signal or baseband signal sent from the hybrid circuit 14 (see FIG. 6) in the analog signal processing section A 10 is input to the hybrid circuit 20 of the digital signal processing section _{D 10 shown} in FIG. be done. The auxiliary signal demodulator 21 demodulates an auxiliary signal for transmission or reception from the analog output signal of the hybrid circuit 20 and inputs it to the delta modulator 28 via the hybrid circuit 22. The delta modulator 28 converts the input analog signal into a digital signal and inputs the digital signal to the synchronization circuit 29 . In the synchronization circuit 29, a digital auxiliary signal is inserted in synchronization with the transmission digital signal PCM IN, and its output is sent as an intermediate frequency signal or baseband signal to the analog signal processing section _A10 via the hybrid circuit 24.
The signal is sent to the internal hybrid circuit 11 (see FIG. 6). After this, the auxiliary signal is sent to the demodulator 1 as described above.
2 and then demodulated and received, or transmitted along with the main signal from antenna TA.

When receiving an auxiliary signal in the digital signal processing unit D ₁₀ , the synchronization circuit 25 receives the output of the hybrid circuit 20, synchronously separates the main signal PCM OUT and the auxiliary signal, and generates the obtained digital auxiliary signal.
SC(D) may be converted into an analog signal by the delta demodulator 26 and received analog auxiliary signal SC(A)OUT may be received via the hybrid circuit 27.

Similarly, when inputting a transmission auxiliary signal in the digital signal processing section _D10 , the analog auxiliary signal for transmission is inputted to the hybrid circuit 22, digitized by the delta modulator 28, and sent to the synchronous circuit 2.
9, it is inserted into the digital main signal for transmission, and the composite signal is transmitted.

Furthermore, according to the circuit shown in FIG. 8, the received analog auxiliary signal can be directly obtained from the hybrid circuit 22, or the transmitted analog auxiliary signal can be input to the hybrid circuit 27 and modulated into an appropriate band by the modulator 23. , it can also be transmitted superimposed on the transmission main signal.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, in a transmitting/receiving device in which an analog signal processing section and a digital signal processing section are arranged separately and independently, an auxiliary signal for transmission is transmitted to a receiving section in the analog signal processing section. After passing through the digital signal processing unit via The auxiliary signal can be digitally inserted into the main signal at low cost and easily without adding an auxiliary signal transmission line between the analog signal processing section and the digital signal processing section. This provides an auxiliary signal insertion/separation method that can digitally separate the auxiliary signal from the main signal.

It also becomes possible to send and receive auxiliary signals between the analog signal processing section and the digital signal processing section within the same station.

Furthermore, the auxiliary signal can also be transmitted and received in the digital signal processing section.

The present invention is not limited to the embodiments described above, and various modifications are possible.

[Brief explanation of drawings]

Fig. 1 is a conceptual system configuration diagram of the auxiliary signal insertion/separation method, Fig. 2 is a block diagram showing an example of the conventional auxiliary signal insertion/separation method, and Fig. 3 is the digital insertion/separation of auxiliary signals. FIG. 4 is a schematic side view showing the arrangement position of the transmitting/receiving device installed on the steel tower; FIG. 5 is a system configuration diagram schematically showing an embodiment of the present invention; FIG.
The figure is a block diagram showing the transmitting side TR shown in Figure 5 in more detail, Figure 7 is a diagram for explaining the state in which the auxiliary signal is superimposed on the main signal, and Figure 8 is the same as Figure 6. FIG. 2 is a block diagram illustrating the illustrated digital signal processing section _D10 in more detail. R... Receiving section, T... Transmitting section, 10... Modulating section, 13... Demodulating section, A ₁₀ ... Analog signal processing section, D ₁₀ ... Digital signal processing section, 16... Synchronization separation circuit, 17 ...Synchronization insertion circuit, SC...Auxiliary signal, PCM IN...Digital signal for transmission.

Claims (1)

[Scope of Claims] 1. A receiving unit having a demodulating unit that demodulates a received signal obtained by combining an auxiliary signal for maintenance management and a main signal, and a modulation unit that modulates the auxiliary signal for maintenance management and the main signal to be combined. and a digital signal processing section disposed in the same station as the analog signal processing section and independently and separately from the analog signal processing section, the digital signal processing section comprising: , a first synchronization section that decodes the demodulated reception signal from the demodulation section to obtain a reception digital signal, and a second synchronization section that encodes and inputs the transmission digital signal to the modulation section, and the analog signal processing The analog auxiliary signal for transmission to be transmitted from the unit to another station or the digital signal processing unit is combined with the demodulated analog reception signal from the demodulation unit, and then synthesized with the demodulated analog reception signal from the demodulation unit.
The auxiliary signal extracted in analog form is extracted from the demodulated reception signal by the synchronization unit and received by the digital signal processing unit, or the auxiliary signal extracted in analog form is converted into a digital signal and the second synchronization unit converts the auxiliary signal into a digital signal. The auxiliary signal for reception in the analog signal processing section is combined with the digital signal for transmission and transmitted to another station via the modulation section, and the auxiliary signal for reception at the analog signal processing section is
The demodulated reception signal from the demodulation section is synchronously separated into a digital auxiliary signal from the main signal by the first synchronization section, the synchronously separated digital auxiliary signal is converted into an analog signal, and then transmitted by the second synchronization section. An auxiliary signal insertion/separation method characterized in that the auxiliary signal is synthesized in an analog manner with a reliable digital signal and then demodulated from the synthesized transmission signal to be received by the analog signal processing section.