FI58241B - COPYING INSTRUCTIONS AT THE MAETA OCH / ELLER OEVERVAKA TRANSMISSIONSKVALITETEN HOS EN DATATRANSMISSIONSANLAEGGNING - Google Patents

Description

ΓΒ1 - «KUMLUTUSjULRAieU cöo / -3® * -m (11) UTLÄGGNI NCSSKMFT 5 8241 C (4S> Fa +: -ni ^ v ^ (51) Kv.ikiWa.3 h (AH 3/22 // H 04 · B 3/46 FINLAND — FINLAND (21) hrn «lh * mu · —htwwemWmliig 2079/73 (22) HekemhpIMl — Aneeknlngrteg 28.06.73 (23) Alkuptlvi — GiMghuttdag 28.06.73 (41) Tullut Julktoksl - BIMt offuntllf 07.06.7 ^

National Board of Patents and Registration / 44) Jt iujU |. | Ullui * m pvm.—

Patent- och registerstyrelsen 'Aratkin utltfd och utl.ikrtfwn published 29.08.80 "(32) (33) (31) Requested« tuolkuu * —Bu * lrd prlorltat 06.12.72

Switzerland-Switzerland (CH) 17772/72 (71) Siemens-Albis Aktiengesellschaft, Albisriederstrasse 2 * + 5> 80 ^ 7 Zurich, Switzerland-Switzerland (CH) (72) Carl Schick, Zurich, Switzerland-Switzerland (CH) (7) * 0 0y Kolster Ah (5 * 0 Switching arrangement for measuring and / or monitoring the transmission quality of data transmission equipment - Kopplingsanordning för att mált och / eller övervaka transmissionskvaliteten hos en datatransmissionsanläggning

The invention relates to a switching arrangement for measuring and / or monitoring the transmission quality of a data transmission device by means of test signals transmitted via a data transmission device covering the entire dynamic range to be transmitted, wherein at least one the course is at least approximately exponential.

Swiss Patent Publication No. * + 95 09 * + discloses a method for monitoring the operation of an encoder and a decoder in a time multiplex system, in which a test signal is generated which has a path over the entire transmitted dynamic range and is routed to the same terminal in the time slot used to generate and / or synchronize the signal. on the one hand via the investigating encoder and decoder and on the other hand directly via the reference circuit, whereby when a predetermined deviation is exceeded, an error indication is given in each case.

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Swiss Patent Publication No. 535,512 discloses another method for monitoring the operation of an encoder and a decoder in a PCM time multiplex system in which a bipolar test signal is generated on the transmission side, the travel of which is at least approximately exponential and which exceeds all quantization stages of the transmitted dynamic range. This signal is then routed through a channel switch to the encoder and through a second channel switch to a decoder of the same terminal, or back to the first terminal via a more distant exchange and channel switch, and is compared here to the original test signal.

If the reference voltage exceeds the reference voltage value, an alarm is issued.

However, this method is adversely affected by the fact that additional control gates are required to compensate for the overall attenuation acting on the entire transmission path, which means additional costs and in turn affects the test result.

The object of the invention is to provide a switching arrangement by means of which the transmission quality of an arbitrary data transmission equipment can be measured and / or monitored on the receiving side, regardless of the general training and time deceleration occurring in the transmission path.

The switching arrangement according to the invention is characterized in that a number of test stages corresponding to the number of test signal generators are provided, each of which can be individually connected to the and / or in terms of number per unit time and / or when a predetermined deviation is exceeded, triggers a fault message.

The coupling arrangement described above will be explained in more detail below on the basis of the accompanying drawings. Figures 1a, 1b and 1c show a block diagram of a circuit according to the invention in connection with a communication apparatus, Figure 2 shows a detailed block diagram of a network and a test site, Figure 3a shows the flow of received signals in case of interference and Figure 3b shows the flow of these signals in case of transmission is disturbed.

During the measurement and / or monitoring of the transmission quality of the communication equipment, a test signal generator PG and a corresponding reception terminal E are connected in each case to the transmitting terminal S.

58241 test site P preceded by network N. It is questionable from the time multiplex transmission equipment that the test signal generator PG, the network N and the test site P can be used to measure and / or monitor several terminals of the time multiplex transmission equipment almost simultaneously along different time channels.

The test signal supplied to the transmitting terminal S and routed through the corresponding transmission channel K and its receiving terminal E can be routed to the test site P at the remote end via the network N. Thus, the transmission quality of the transmission channel and the associated transmission and reception terminal equipment can be measured and / or monitored (Figure 1a).

Similarly, the transmission quality of both transmission directions of a four-wire connection can be measured and / or monitored from one end of the four-wire connection.

a test signal conducted through the transmission channel K of the transmitting terminal S and the receiving terminal E of the second transmission direction at the far end of the four-wire connection to the switching stage PS recognizing this test signal

the second transmission direction to the transmission-side terminal S and thus via the corresponding transmission channel to the reception-side terminal E at the source of the test signal and from there via the network N to the test site P (Fig. 1b).

Furthermore, the transmission quality can also be measured and / or monitored from the transmitting and receiving terminals at the same end of the four-wire connection, e.g. measuring and / or monitoring the encoders and decoders of the PCM time division multiplexing apparatus in a time slot which is not used for data transmission. In this case, the test signal conducted to the transmitting terminal S is fed to the receiving terminal E at the same end of the four-wire connection and via the network N to the test site P for the duration of the measurement and / or monitoring via the test connection PV (Fig. 1c).

The number of test signal generators PG, networks N and test sites P depends on the number of transmission channels K of the communication equipment, the transmission quality of which must be monitored and / or measured at the same time.

In the transmission-side test signal generator PG, a test signal is generated "having at least an approximately exponential path corresponding to the dynamical range to be transmitted.

This test signal S1 is passed on the receiving side via a network N having a transmission function at least approximately equal to the second mathematical function derivable from the first mathematical function, and is then passed as a converted signal S5 from the network N to the test site P. The transformation of this converted signal S5 is compared which at least approximately corresponds to a third mathematical function derivable from the first and second mathematical functions.

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The structures of the network N and the test site P thus depend on the flow of the test signal generated by the transmission-side test signal generator PG. Such a test signal, the passage of which at least approximately corresponds to the function e, resp, -e, resp.

"X" "X

e, vast, -e, an integrated signal S2 can be formed in the integrator I of the receiving side network N. For this integrated, signal S2, a path is obtained which at least approximately corresponds to the function -ex, resp. ex, vast, -e x, vast, e x.

The smaller the deviations of the test signal, in particular the received test signal S1, from the course of the exponential function, the smaller the deviations of the integrated signal S2 from the course of the integral of that exponential function. The integrated signal S2 is amplified in the amplifier V1 connected downstream of the integrator I to such an extent that its amplitude is at least approximately equal to the amplitude of the received test signal S1. The received test signal S1 and the amplified integrated signal S2 are then summed, resulting in a resulting signal S3 with an amplitude at least approximately constant. The more closely the course of the received test signal S1 corresponds to some function e, vast, e, vast, -e vast, -e, the more the course of the resulting signal S3 approaches a linear function whose amplitude is constant. This flow of the resulting signal S3 thus provides information on how the test signal generated on the transmission side enters the receiving end of the data transmission equipment. Thus, in order to measure and / or monitor the transmission quality of the communication equipment, the course of the function of the resulting signal S3 must be examined on the receiving side.

During the positive half-wave of the bipolar test signal S1, a resultant signal S3 having a first constant amplitude is generated, and during a negative half-wave, a resultant signal S3 having a second constant amplitude is generated. In order to simplify the interpretation of these signals, which are at least approximately square, the resulting signal S3 is first fed to the network N via a high-pass filter H1 and is thus released from its direct current, DC component. The resulting signal S * + thus obtained has at least an approximately claw-shaped path with a positive and a negative half-wave. The signal is rectified in a rectifier G connected after the high-pass filter H1, and fed as a converted signal S5 to the output of the network N. This transformed signal S5 now has at least an approximately linear path and a constant amplitude throughout the bipolar test signal S1 in the case of transmission.

The converted signal S5 from the network N is routed to the test site P connected after the network N, where the converted signal S5 is compared with its DC current. to the reference signal S6 derived from the DC component. To this end, the converted signal S5 is applied at the test site P via the high-pass filter H2 and then the first amplifier V3 connected to the second input of the analog signal reducer D and directly to the second input of this analog signal reducer D via the second amplifier V2. The reference signal S6 obtained from the output of the analog signal reducer D then corresponds to the converted signal S 'released from its direct current component.

Of course, the reference signal S6 can also be obtained by passing the converted signal S5 through a high-pass filter.

The transformed signal S5 amplified at the test site P and the reference signal S6 are then applied to the reference stage K. The more closely this transformed signal S5 corresponds to a constant amplitude linear function, the smaller the difference between the instantaneous values of the converted signal S5 and the reference signal S6 formed in the reference stage K.

^ The measuring signal S7 obtained from the reference stage K, corresponding to the magnitude of the current difference, is fed to a measuring and / or alarm device, where a fault indication is triggered when the specified permissible difference is exceeded.

In PCM time-division multiplexed telephone and / or music transmission equipment, analog-to-digital, digital-to-analog converters derived from the quantization stages in the encoder, decoders, usually have more frequently staggered values over the entire amplitude of the analog signal to keep relative distortions. area. A bipolar test signal having at least an approximately exponentially attenuating path thus has a characteristic curve similar to the quantization characteristic of an analog-to-digital or digital-to-analog converter. The advantage of this is that the decreasing instantaneous values of the test signal also cause a larger number of sounding samples to be generated. This makes it possible to monitor all degrees of quantization in the dynamic range with a single aperiodic bipolar test signal with at least an approximately exponentially attenuating path, and to detect possible irregularities if the temporal length of two consecutive half-waves number of inputs.

Continuous monitoring can thus only be achieved with a periodic test signal whose frequency is suitably determined by analog-to-digital equivalents. the number of quantization stages of the digital-to-analog converter and the sounding frequency.

Instead of an at least approximately exponentially attenuating bipolar test signal generated on the transmission side, a test signal with an exponentially ascending path can be used, for example, for PCM time multiplex transmission equipment with a straightforward quantization characteristic.

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For PCM time-division multiplexing equipment operating at an audio frequency of 8 kHz and using encoders or decoders with 256 quantization stages, the frequency of the periodic test signal is suitably selected to be 30 Hz. The exponentially attenuating test signal is obtained, for example, by differentiating the ac-shaped alternating voltage.

Claims (6)

7 58241 A switching arrangement for measuring and / or monitoring the transmission quality of a communication device by means of test signals transmitted via a communication device covering the entire dynamic range to be transmitted, wherein at least one individually switchable test signal is generated in ), the flow of which is at least approximately exponential, characterized in that a number of test stages (P) corresponding to the number of test signal generators (PG) are provided, each of which can be - individually connected via a network (N) in each test stage (P) to receive test signals. (K) to the receiving-side terminals (E), which network (N) is capable of converting the approximately exponential input input (SI) into an approximately constant DC voltage signal (S5) and which test stage (P) indicates the DC voltage of the network (N) deviations in the size and / or number per time unit in the output signal (S5) and / or when a predetermined deviation is exceeded, triggers an error message. Switching arrangement according to Claim 1, characterized in that the received test signal (S1) in the network (N), after it has passed through the integrator (i) and the amplifier (V1), forms an integrated signal (S2) with at least approximately the same amplitude. and it is summed with the test signal (S1) received in the analog signal adder (A), and the resulting signal (S3) is released from its DC, DC components in the high-pass filter (H1), rectified in the rectifier (G), and the resulting output signal (S5) is applied. Switching arrangement according to Claim 1 or 2, characterized in that the output signal (S5) of the network (N) in the test stage (P) is fed via a high-pass filter (H2) and a first amplifier (V3) connected behind it to the second input of the analog signal reducer (D). via a second amplifier (V2) to the second input of the analog signal reducer (D) and that the output signal (S6) of the analog signal reducer (D) is compared as a reference signal in the reference stage (K) to the output signal (S5) of the network (N) amplified by the second amplifier (V2) and the resulting output signal β 58241 A switching arrangement according to claim 1 for transmitting a four-wire connection comprising the respective transmitting and receiving terminals and transmitting or transmitting terminals, indicating the respective magnitudes and / or the number of deviations per unit time and / or the occurrence of a predetermined deviation. that the transmitting and receiving terminals (S, E) are connected via a test signal generator (PG) network to the test stage (P) and that the transmitting and receiving terminals at the other end of the four-wire connection (S, E) are transiently interconnectable when the test signal occurs through a switch stage (PS) identifying the test signal (Figure 1b). Switching arrangement according to claim 1 for measuring and / or monitoring the transmission quality of transmission and reception terminals of data transmission equipment located at the same terminal, characterized in that the transmission, reception terminals (S, E) are network (N) of a test signal generator (PG). via the connection to the test stage (P), and that the same transmission and reception terminal equipment (S, E) can be connected via a switched-through test connection (PV) for measurement and / or monitoring (Fig. 1c). Switching arrangement for measuring and / or monitoring the transmission quality of a time-division multiplexing device according to Claim 1 or one of Claims 2 to k, characterized in that a network signal tester N) and the corresponding test step (P). 58241 *