JPS58197943A - Supervisory signal transmission system for direct relay station of digital wireless circuit - Google Patents

Abstract

PURPOSE:To realize the high-quality transmission of a supervisory signal by performing slightly the modulation of a main digital modulation wave of subcarrier modulated by the supervisory signal. CONSTITUTION:A data train outputted from a parallel-serial converter 151 is given band limitation on it by an LPF, supplied to an AM modulator 154 and modulate a subcarrier oscillated by a oscillator 155 to AM. The AM modulated subcarrier is supplied to the AM modulator of a relay station as a modulation signal and slightly modulate the amplitude of main digital modulation wave to be directly relayed. The amplitude modulated digital modulation wave is amplified and outputted from an antenna. A composite modulation wave which become a medium frequency after received by the receiver of a terminal station is supplied to an input terminal 41 of a demodulator, and a supervisory signal is demodulated by a detector 42 and LPF43 for eliminating a medium frequency. By this system, the high-quality transmission of a supervisory signal can be realized because almost no deterioration occurs on main digital modulation waves.

Description

[Detailed description of the invention]

[@Ming.AM Field] The present invention relates to a supervisory signal transmission system in a digital wireless direct relay station for transmitting a supervisory signal sent to the digital wireless direct relay station to a terminal station. 】Technical secret of invention) No digital! The monitoring signal transmission method at the relay station of the iiiAgI line is to convert the raw digital signal to phase shift 1.
Taking the case of m (PSK) as an example, conventionally there are the following (1) and C), and (3) is also possible. (1) The transmission speed of the main digital signal is increased, and a monitoring signal is inserted into the surplus bits for transmission. (2) Phase shift shift 1111 (PSK) technique transport station monitoring No. 16 transmits shallowly in frequency position ii1 (FM) and Fi @ wave number shift shift (FSK) l. (3) Transmit a phase-shift keyed (PSK) wave with a shallow amplitude change of 1 (AM) as a monitoring signal. FiP that changes shallowly
This is to prevent the transmission characteristics of sKa from deteriorating. [Background technology] However, method (1) requires PSK recovery at the relay station.
11, a data rate converter, and a PSK modulator are required, and the method in 90) requires a local oscillator for frequency modulation or Fi frequency shift modulation. 1. An rk connected relay device that easily performs relaying with low power consumption cannot be used. In addition, method (3) is suitable for direct relay equipment with low power consumption (a
) When the ratio between the transmission speed of the P8K signal and the transmission speed of the supervisory signal becomes small, the amplitude component of the FSKQ signal interferes with the supervisory signal, degrading the 87N of the supervisory signal, and causing the code WA9 to appear in this pigeon-neck supervisory signal. Therefore, the supervisory signal cannot be transmitted.佽) To improve the 87N @ protection of the monitoring signal, it is necessary to lower the transmission speed, but if the transmission speed of the monitoring signal is low, the receiving intermediate frequency automatic gain controller (IP, mu GC) of the terminal station should be lowered. The response speed is determined by O having an All component (for example, 1iz) that follows the attenuation speed fK due to the 7 ages of radio waves.
The M1 code is suppressed by 111F-AGCK, causing a problem with the code and making it impossible to identify the code. So, in the end, the transmission Fi of the TIIL visual signal was extremely poor. [@k14(I) Purpose] □ The present invention is a digital radio-edge direct relay station.
An object of the present invention is to provide a digital wireless supervisory signal transmission system capable of transmitting supervisory signals with high quality. [Summary of the Invention] Therefore, in the present invention, the monitoring signal of No. 41I in the station of the #'i direct relay network is digitally encoded, and the received AGC response of the terminal station is digitally modulated using the encoded monitoring signal. By transposing the copper carrier at a frequency sufficiently lower than the speed of the wave or by several ridges, and by shallowly transmuting the main digital Is wave with the transposed subcarrier, the monitoring signal is generated. The terminal station transmitting from the direct relay station performs envelope detection on the received signal from the direct relay station to detect the lIl carrier wave.
Then, the above-mentioned monitoring signal is improved by further envelope detection #L or IM technique discrimination of the carrier wave. will be explained in detail with reference to the attached drawings. Figure 1 shows an example of a 91-connection relay station to which the supervisory signal transmission system in a digital wireless line direct relay station according to the present invention is applied. This direct relay station Fi is capable of two-way communication, from the antenna input/output terminal 1 to the antenna duplexer 2, receiver subwoofer 3, low noise field width amplifier 4, AM modulator 5, power amplifier 6, and transmitter. A first system leading to the antenna input/output terminal 9 via the wave submersor 7 and the antenna duplexer 8, the antenna duplexer 8 from the air input/output terminal 9, the receiving waver 10, and the low noise amplifier 11. Through the AM converter #1 12, the power amplifier 13, the transmitter 14, and the antenna duplexer 2, the second line is connected to the center line input/output terminal IK, and the upper line 1 system and the second system. A
It has a subcarrier modulation path 15 that supplies a frame A6 to an M variable [fF5.12. Subcarrier modulation 1 path 15 (1,
) N-#l#i can be seen in FIGS. 2 and 3. Here, the number 2I81 is the subcarrier modulation 1 path 15.
Figure 3 shows the situation using the AM (AM) subcarrier sound. As the li path 15, the binary frequency deviation N
(FSK) is used to show the location. First of all, I am impressed by the sound made using the amplitude 5L sea bream shown in Figure @2 as the 1lls feed temporary change 11 oil path 15. In Figure 2, monitoring information input terminals 'r,,'r2~i
A plurality of pieces of monitoring information manually inputted to n are input to the parallel-to-serial converter 151. The parallel-to-serial converter 151 converts a plurality of pieces of monitoring information inputted to the monitoring information input terminals TI+' to Tn into a serial data string in response to a clock pulse generated from the clock pulse generator 152, and also converts this data data into a serial data string. A four-side signal and a station-specific signal are added to the blur, and a parity pit is added to the end of this data string. In addition, Fig. 4 11 Parallel-direct Taly conversion! Amanoso AFi shows the frame structure of the data string output from 151.
Synchronization signal, B#i station identification signal, DI-DB IIi monitoring information input terminal TI, monitoring information input to Ding-Tn, P is a parity bit. A data string having a frame structure as shown in FIG.
The receiver is then applied to AM modulator 154. The subcarrier oscillated from the subcarrier oscillator 155 is M[-. Subcarrier oscillation here! 155 is used which generates a signal having a frequency higher than the reception frequency of the GC response of the terminal station, which will be described later, and sufficiently lower than the transmission speed of the main digital signal used in this digital signal. AM weird! 146154
The AM modulated subcarrier is the AM modulator 5 shown in Figure @1.
．． 12 as a modulation signal and the main digital modulation signal to be broadcast live.

[Shallow < 1 wheel change-. That is, the digital converter signal input to the antenna input/output terminal 1 and to be directly relayed (signal to P8) is guided to the low-noise amplifier 4 via the antenna duplexer 2 and the receiving polarizer 3. The output t of this low noise field IkA device 4 is shallowly amplitude-modulated by the output of the imprinted wave transformer circuit 15 in the AM transformer 5, and is used to block the power amplifier 6, the transmitter filter 7, and the antenna duplexer 8. The signal is then output from the antenna input/output terminal 9. Furthermore, the digital modulation M (PSK signal) input to the receiver input terminal 9 is transmitted to the antenna duplexer 8,
Low noise amplification via receiver IO! 11, the output of the low noise field unit 11 is changed to a shallow amplitude KN by the output of the subcarrier modified chest circuit 15 in the AM converter 12, and then sent to the power amplifier 13, the transmitter 4g/0jL unit 14, and the antenna shared 62. Antenna input via, ・l::l''' l・,・
, 1 output terminal]. Next, a case will be described in which the side carrier wave modulation circuit 15 has the configuration shown in FIG.
By switching the output of b with an electronic switch 156 according to the output of the parallel-to-serial converter 15, a binary FSK modulation output t is obtained.
- This binary FSK modulation output is added to the AM modulator 5.12 in FIG. 1, and the main digital modulation at AM is performed as in the case described above. In addition, in FIG. 3, parallel-to-serial conversion 6151 and clock pulse generator 152 [4
It is the same *& as that indicated by the same symbol in 2-, and is composed of a digital collection circuit with low power consumption. FIG. 5 shows a good example of a terminal station receiver to which the method of the present invention is applied.
The complex KPM and monitoring signals are input to the receiver input terminal 31, the low noise is amplified by the amplifier 32, and then the frequency is converted by the frequency converter 8134, where the output of the local oscillator is applied, and the intermediate JiId signal is input to the receiver input terminal 31. Then, the adjacent construction cost rBL applied to the intermediate frequency band three-wave amplifier is removed, and the signal is amplified to the desired level by the intermediate frequency band three-wave amplifier with AGC. This intermediate 1M wave with AGC - Gangbang output t is output to the Nakaseki chest wave output terminal 37, and is also output to the [class relay station 4 to 1
The signal is input to No. 6 demodulator A. , directly after the relay station monitoring signal I
Ij4IliA is the output of the intermediate frequency amplifier with AGC, which directly modulates the wIL visual signal of the relay station (to 31) and outputs it to the terminal. Figures 6 and 7 show this direct relay station monitoring signal demodulator. Figure 6 shows a case where the configuration of Figure 2 is taken as one carrier wave changing H circuit 15 (Figure 1) of the direct relay station, and Figure 7 shows the configuration of the direct relay station. If #g in FIG. 3 is taken as one carrier modulation circuit 15 of ttt
- Shows. First, the configuration shown in FIG. 6 will be explained. The main PSK signal and the supervisory signal, which have become intermediate jiill&, are added to the demodulator input terminal 41 and are detected by the detection signal 42.
, a subcarrier modulation signal is demodulated by the interharmonic elimination low frequency waveform 43, and the monitoring signal is demodulated by the detector tIL unit 44 and the -1 carrier wave elimination low frequency waveform 645. The output of the subcarrier removal low frequency waveform generator 45 is shaped into a pulse by a waveform shaper 46, and then a clock is configured by a clock regeneration circuit 47, and the pulse is identified by a discrimination circuit 6. At L2, the temporally serial data string is converted into parallel data and output from output terminals t1 to tnWc. In this way, the direct relay station monitoring information is obtained from the output terminals t1 to 1n as the IJ data. Next, box I in Figure 7
! t will be explained. Detection 44, subcarrier removal low frequency waveform generator 45, waveform shaper 4
6 to Imperial region 5a equipment 53, 52, detection profit 53, 54,
It can be constructed by replacing it with the waveform shaping and sum circuit 55. Here, the band waver 51 adjusts the oscillation frequency of the subcarrier wave generator 155 & shown in FIG.
The number of oscillation plates of the subcarrier oscillator 11i 155b shown in the figure is respectively IWl@. In other words, the circuit shown in FIG. 7 discriminates the 1li11 carrier frequency using band wavers 51 and 52, detects this using detection gains 53 and 54, and then adds the waveform shaped sum U approximately 55 and directly outputs the signal from the relay station. Monitoring signal is 0! - to do. Note that the other parts are the same as the path (2) in FIG. 6. In FIG.
The configuration shown in the figure is adopted, and the terminal station receiving machine is installed in the 11) 5 monitoring station @! - For reference, this is a diagram showing the corrugated pipes of each part of the lifting platform constructed as shown in Figure 6. i.e. #! Figure 8(a)
The output waveform of the Fi parallel-to-serial converter 151 and the output waveform of the green circuit, the output waveforms of the low-frequency wave generator 153 and the low-frequency wave generator 153 and the reduced carrier wave generator, #! Figure 8 (C)
The output waveform of the FiAM modulator 154 (1M carrier technique modulation -
15 output waveform) and intermediate frequency removal low frequency waveform filter 43
FIG. 8(d) shows the output waveform of the mid-range amplifier with GC. [Effects of the Invention] As explained above, according to the method of this @Sushi, the main digital modulation #lI 4 wave is shallowly modulated by the subcarrier transformed by the demagnetization code, so the main digital modulation wave is not degraded. #1: There are very few things I can do. It goes without saying that this should be the case, but according to the present invention, even if the transmission speed is slowed down to ensure the S/N ratio of the monitoring signal, the frequency of the Iimigo signal component is shifted by the #&li carrier wave. Reception (F
Since it is not suppressed by the GCK of the stage, no waveform distortion occurs. Therefore, the monitoring signal can be transmitted with high quality.

[Brief explanation of the drawing]

Fig. 1 is a program diagram showing an embodiment of a relay station using the method of the present invention, Fig. 2 is a detailed block diagram explained in the section 'of Fig. 1, and Fig. 3 is a Figure 4 is a block diagram showing another example of the configuration of Figure 2;
The figure is a block diagram showing an embodiment of a terminal station receiver (g4!) to which the method proposed by Meiji Honto is applied, a detailed block diagram showing the closing part of Fig. A block diagram showing an example of the configuration of the circuit. Fig. 8 is a waveform diagram illustrating the operation of one circuit shown in Figs. 1, 2, 5, and 6. 1.9... Air-in Output terminal, 2, 8...Aerial trout duplexer, 3.lO...Receiving waver, 4,11 Low noise amplifier, 5, 12・AM converter, 6, 13
= 11E power jll1 width device, 7.14...Creeping wave device,
ib...Strict transmission wave conversion circuit, 31...Receiver input terminal; 32...Low noise f amplifier, 33.Local oscillator, 3
4... Frequency IBL number converter, 35... Intermediate frequency intensifier # & device with AGC, 37... Intermediate frequency booster with AGC, 37... Nakanoseki Liu wave output terminal, Awesome... Direct relay station (Visual signal recovery-1T,
-Tn...Monitoring information input terminal, 11~t0...Monitoring information output terminal Fig. 1 Fig. 2 Fig. 3 TIT2 Tn T
IT2 Tn No. 4

Claims (1)

[Scope of Claims] (1) The monitoring signal of the in-station equipment of the ML relay station is encoded by psital coding and the monitoring signal is encoded by the 4M signal. By shallowly converting the main digital P4 technique using the incoming wave, the monitoring signal is sent from the @11 relay station, and the terminal station performs envelope detection on the received signal from the direct relay station. Said #&I
l! After the MI transmission m is hooked, the thin noodle transmission is further unhooked in the mode ag2 corresponding to the mode 1 of the Ml and sent to the direct relay station of the digital wireless line to output the monitoring value number t-*p. Monitoring signal transmission method. Q) The predetermined frequency is the reception AGC at the terminal station.
A supervisory signal transmission system in a direct relay station of digital radio 1ial&l as claimed in claim 1, which is higher than the response frequency and sufficiently lower than the transmission rate of digital tear harmonics. (3) The aspect of @l is amplitude variation, and the second
Mr. Juku is a 1M signal transmission method at the direct relay station of the digital wireless IGL line described in paragraph (1), which is enveloped line detection. (4) The LL connection relay station for digital wireless I/M line according to claim 0), wherein the first mode is frequency shift modulation, and the second mode IIIA is frequency discrimination. supervisory signal transmission method.