DE102004036752A1 - Broad band system for use in subscriber telephone exchange, has subtraction equipment, which subtracts generated compensation signal from transferred broad band signal, so that error compensated broad band signal is designed - Google Patents

Abstract

The system has an integrated adaptation equipment (2), which adaptively generates a compensation signal (KS) from a received broad band signal. The broad band signal is transferred with a boosted sinusoidal signaling signal of an activating system (3). A subtraction equipment (10) subtracts the generated compensation signal from the transferred broad band signal, so that an error compensated broad band signal is designed. An independent claim is also included for a subscriber telephone exchange with a broadband system.

Description

The The invention relates to a broadband system with generation of a compensation signal for error compensation of a superimposed received wideband signal and a local exchange with such a broadband system.

The Technical field of the invention relates to the transmission of speech signals in a baseband and the simultaneous transmission of data signals in a higher Frequency band over a common subscriber line. In simultaneous transmission of voice signals and data signals over a common subscriber line there is the problem that within an integrated data / voice local exchange Interference between an amplified signaling signal associated with the speech signal and the data signal or broadband signal occur. A local exchange consists essentially of a language system (eg telephone) and a broadband system (eg ADSL system). Problematic are the signaling signals with a high signal level (for example the TTX (teletax) signal), which at a frequency of 12 or 16 kHz up to 5 Vrms the subscriber line is, and their higher harmonic Harmonics caused by nonlinear properties in the reinforcement the signals through the subscriber line circuit (SLIC = Subscriber Line Interface Circuit) of the speech system. The disturbing harmonic harmonics the upstream signals of ADSL data transmission (ADSL = Asymmetric Digital Subscriber Line). This problem occurs both with Integrated Voice Data (IVD) solutions and in DSLAM solutions on, which by means of splitter filter high order with the language system POTS system (POTS = Plain Old Telephone System) are connected.

The Fundamental wave of the distorted amplified Signaling signal or the TTX signal can by steep-edged, passive LC filters (high-pass and low-pass filters) can be reduced. The negative influence of harmonic harmonics of the amplified signaling signal is through appropriate increase minimized the so-called margins of the affected carrier. An increase in the Margins means an increase the reserve for the signal-to-noise ratio. Both measures But at the expense of the data rate and can sometimes lead to the connection abort to lead.

For example is in the unpublished Patent Application "Broadband System and local exchange "with the reference 102004014969.0 describes a broadband system which an adaptation device, which is to be sent to a broadband signal adds a compensation signal. The superimposed with the compensation signal Broadband signal to be sent is by means of a separation filter with a distorted amplified Signaling signal of a speech system superimposed, so by means of the Compensation signal occurring during amplification distortion the signaling signal is compensated. The adaptation loop for generating the compensation signal is here by the broadband system and formed by the separation filter.

The Object of the present invention is therefore a broadband system with an error compensation for one with a reinforced one Signaling signal superimposed provide a received wideband system, so that a detection error a subsequent Detection of the received broadband signal due to the interference by the reinforced Signaling signal is avoided.

A Another object of the present invention is the error compensation for the superimposed received broadband signal by means of a short adaptation loop provide.

According to the invention Asked problem by a broadband system with the features of the claim 1 and by a local exchange with the features of claim 15 solved.

The The idea underlying the present invention consists essentially in it, a broadband system for sending and receiving broadband signals to provide with an integrated adaptation device, which a compensation signal from the received wideband signal, the with a reinforced sinusoidal Signaling signal superimposed on a couplable with the wideband system voice system is adaptively generated and the generated compensation signal from the superimposed Subtracted received wideband signal, so that an error-compensated received wideband signal is formed.

The inventive broadband system provides thus ensuring that broadband signals or ADSL data are in a higher frequency band without disturbances the fundamental and harmonic harmonics of the amplified signaling signal are detectable.

Another advantage of the invention is that the compensation signal is directly within the wide is subtracted from the superimposed received wideband signal for error compensation, so that a short feedback path is provided within the broadband system. The short feedback path means a lower delay of the adaptation of the compensation signal and thus a faster adaptation of the error compensation.

advantageously, is the generation of the compensation signal independent of the linkable language system or POTS system, so that the language system, which with the broadband system to a local exchange or to an IVD solution can be coupled, can be any of any manufacturer.

advantageous Refinements and developments of the invention will become apparent the dependent claims and the description with reference to the drawings.

According to one preferred embodiment of the invention has the adaptation device a distance signal generator, which from the error-compensated received wideband signal, a distance signal generated by a harmonic distance between the superimposed received wideband signal and a detected noise-free wideband signal and by a fundamental oscillation distance between the fundamental of the amplified sinusoidal signaling signal and the signaling signal of the speech system is formed.

According to one Another preferred embodiment has the adaptation device an adaptation signal generator, which consists of the distance signal generates an adaptation signal that consists of a phase difference and an amplitude difference of the fundamental and N phase differences and N amplitude differences of the harmonics of the amplified sinusoidal signaling signal and of the sinusoidal Signaling signal exists.

According to one Another preferred embodiment has the adaptation device a compensation signal generator, which receives the compensation signal generated by means of the adaptation signal.

According to one Another preferred embodiment, the compensation signal generator a fundamental tone generator showing the phase difference and the amplitude difference of the fundamental receives and from this generates a fundamental vibration compensation signal.

According to one Another preferred embodiment, the compensation signal generator N harmonic tone generators, where the i-th harmonic tone generator the ith phase difference and the i-th amplitude difference to the i-th harmonic receives and from this generates an ith harmonic compensation signal, wherein i ∈ [1; ...; N] (This condition applies to the entire description).

According to one Another preferred embodiment has the adaptation device a summation device, which the fundamental vibration compensation signal and the N harmonic compensation signals for forming the Compensation signal added selectively. Advantageously, by the selective addition of the fundamental oscillation compensation signal and the N harmonic compensation signals achieves that Compensation signal to given and changing conditions, such as B. the arrival and decay of the signaling signal, adaptable is.

According to one Another preferred embodiment has the adaptation device a first subtraction device which generates the generated compensation signal from the superimposed one subtracted broadband signal received.

According to one Another preferred embodiment, the distance signal generator a fast Fourier transformer, which the error-compensated received wideband signal in a Fourier-transformed error-compensated Broadband signal transformed.

According to one Another preferred development is the fundamental oscillation distance from the coefficient for the fundamental of the Fourier-transformed error-compensated received wideband signal formed.

According to one Another preferred embodiment, the distance signal generator a decision device which, starting from the Fourier-transformed error-compensated received wideband signal on the noise-free Broadband signal decides.

According to one Another preferred embodiment, the distance signal generator a second subtraction device, which determines the harmonic distance from the difference of the noise-free detected wideband signal and the error-compensated received wideband signal.

According to a further preferred development, the distance signal generator has a first bandpass filter which bandpass filters the error-compensated received broadband signal in such a way that the distance signal generator generates the fundamental oscillation distance from the bandpass filtered error compensated received wideband signal.

According to one Another preferred embodiment, the distance signal generator N second bandpasses on which the error-compensated received wideband signal respectively such bandpass filtering, so that the distance signal generator the harmonic distance from the bandpass-filtered error-compensated received wideband signal.

The Invention will be described below with reference to the schematic figures specified embodiments explained in more detail. It shows:

1 a schematic block diagram of a first preferred embodiment of the inventive terminal exchange, which is coupled to a subscriber terminal;

2 a schematic block diagram of a second preferred embodiment of the distance signal generator of the broadband system according to the present invention;

3 a schematic block diagram of a third preferred embodiment of the distance signal generator of the broadband modem according to the present invention;

4 a schematic block diagram of a fourth preferred embodiment of the distance signal generator of the broadband system according to the present invention;

5 a schematic block diagram of a second preferred embodiment of the adaptation signal generator and the compensation signal generator of the broadband system according to the present invention; and

6 a schematic block diagram of a third preferred embodiment of the adaptation signal generator and the compensation signal generator of the broadband system according to the present invention.

In all figures are the same or functionally identical elements and signals - if nothing else is stated - with the same reference numerals have been provided.

Even though the present invention with reference to broadband systems and subscribers, it is not limited to but in many ways used.

1 shows a schematic block diagram of a first preferred embodiment of the subscriber exchange according to the invention 16 , which with a subscriber terminal 19 is coupled. The local exchange 16 has a broadband system 1 , z. As an ADSL system, a separation filter 17 , z. A hybrid filter, and a speech system 3 , z. As a phone on. The separation filter 17 couples the broadband system according to the invention 1 and the language system 3 such that wideband signals of the broadband system 1 , z. B. received broadband signals eBS, and speech signals SpS of the speech system 3 on a single subscriber line 18 are transferable.

The broadband system 1 receives via the separation filter 17 the wideband signal eBS to be received, which is provided with an amplified sinusoidal signaling signal verSS of the wideband system 1 coupled language system 3 is superimposed. The superimposed received wideband signal eBS + verSS is by means of an AD converter 22 converted from an analog signal to a digital signal. The broadband system 1 for transmitting and receiving broadband signals has an adaptation device 2 which adaptively generates a compensation signal KS from the superimposed received broadband signal eBS + verSS and the generated compensation signal KS from the superimposed received broadband signal eBS + verSS by means of a first subtraction device 10 is subtracted, so that an error-compensated received wideband signal feBS (feBS = eBS + verSS - KS) is formed. The adaptation device 2 Detects from the error-compensated received wideband signal feBS a detected wideband signal detBS, which is noise-free.

The adaptation device 2 has a distance signal generator 4 , an adaptation signal generator 5 and a compensation signal generator 6 on. The distance signal generator 4 generates a distance signal DS from the error-compensated received wideband signal feBS. The adaptation signal generator 5 the adaptation device 2 generates an adaptation signal AS from the distance signal DS. The compensation signal generator 6 the adaptation device 2 generates the compensation signal KS by means of the adaptation signal AS.

By the error compensation of the superimposed received broadband signal eBS + verSS by means of the compensation signal KS, errors in the detection of the noise-free detected wideband signal detBS are minimized. If the error rate in the detection is minimized, the data rate for the broadband system can be increased accordingly. So are the broadband signals or ADSL data detectable without disturbances of the amplified sinusoidal signaling signal verSS. Furthermore, according to the invention, the generation of the compensation signal KS is independent of the coupleable speech system 3 or POTS system, so the language system 3 , which with the broadband system 1 to the local exchange 16 or can be coupled to an IVD solution, any language system 3 of any manufacturer. Advantageously, the adaptation loop is within the adaptation device 2 for the adaptive generation of the compensation signal KS short. The short adaptation loop causes a slight delay in the generation of the compensation signal and thus a rapid adaptation of the adaptation device 2 Changing framework conditions of the overall system.

2 shows a second preferred embodiment of the distance signal generator 4 of the broadband system 1 according to the present invention. The distance signal generator 4 receives the error-compensated received wideband signal feBS, which is formed from the difference of the superimposed received broadband signal eBS + verSS and the compensation signal KS, and generates therefrom the distance signal DS, which is represented by a harmonic distance OD between the superimposed received wideband signal eBS + verSS and the detected noise-free wideband signal detBS and by a fundamental oscillation distance GS between the fundamental of the amplified sinusoidal signaling signal verSS and the signaling signal is formed.

For this purpose, the distance signal generator has a fast Fourier transformer 7 which transforms the error-compensated received broadband signal feBS into a Fourier-transformed error-compensated received wideband signal _feBSfft . The fundamental oscillation _distance GD is formed from the coefficient for the fundamental oscillation of the Fourier-transformed error-compensated received wideband signal _{feBS fft} . The distance signal generator 4 also has a decision maker 12 on which transformed Fourier the error-compensated received wideband signal FEBS _fft receives and starting from the Fourier transformed error-compensated received wideband signal FEBS _fft to the noise-free wideband signal detBS decides. Next, the distance signal generator 4 a second subtraction device 13 which calculates the harmonic _distortion OD from the difference of the noise-free detected wideband signal detBS and the Fourier-transformed error-compensated received wideband signal _feBSfft . In the in 2 In the embodiment shown, the distance signal DS is formed by the fundamental oscillation distance GD and by the harmonic distortion OD.

3 shows a schematic block diagram of a third preferred embodiment of the distance signal generator 4 of the broadband system 1 according to the present invention. The embodiment according to 3 differs from the embodiment according to 2 in that the distance signal generator 4 continue a first band pass 14 which bandpass filters the error-compensated received broadband signal feBS such that the distance signal generator 4 provides the fundamental swing distance GD directly from the bandpass filtered error-compensated received wideband signal feBS.

4 shows a schematic block diagram of a fourth preferred embodiment of the distance signal generator 4 of the broadband system 1 according to the present invention. The distance signal generator 4 according to 4 N has second bandpasses 15 each of which bandpass-filters the error-compensated received wideband signal feBS so that the distance signal generator 4 provides the harmonic distance OD from the bandpass filtered error-compensated received wideband signal feBS. Furthermore, the distance signal generator 4 the first bandpass 14 on which - as in 3 represented - the error-compensated received wideband signal feBS so bandpass filtered, so that the distance signal generator 4 provides the fundamental swing distance GD by means of the bandpass-filtered error-compensated received wideband signal feBS.

5 shows a schematic block diagram of a second embodiment of the adaptation signal generator 5 and the compensation signal generator 6 of the broadband system 1 according to the present invention. As already in 1 shown, has the adaptation device 2 the adaptation signal generator 5 which generates from the distance signal DS an adaptation signal AS which comprises a phase difference φ _GS and an amplitude difference A _{GS of} the fundamental _oscillation and N phase differences φ _i.OS and N amplitude differences A _{i.OS of} the N harmonics of the amplified sinusoidal signaling signal verSS and of the sinusoidal signaling signal exists. Without limitation of generality are in 5 only the phase differences φ _1.OS , φ _2.OS and the amplitude _differences A _1.OS , A _{2.OS of} the first two harmonics of the signaling signal shown.

The compensation signal generator 6 receives the adaptation signal AS. For signal processing, the compensation signal generator 6 sometimes a fundamental vibration sound generator 7 which receives the phase difference φ _GS and the amplitude difference A _{GS of} the fundamental and from this a fundamental vibration compensation signal GKS generated. Further, the compensation signal generator 6 has N harmonic tone generators 8th wherein the i-th harmonic _{tone generator} 8-i _receives the i-th phase difference φ _i.OS and the i-th amplitude _difference A _i.OS to the i-th harmonic and generates therefrom an i th harmonic compensation signal i.OKS. Without limitation of generality are in 5 only the first harmonic tone generator 8-1 and the second harmonic tone generator 8-2 shown. For example, the first harmonic tone generator receives 8-1 the first phase difference φ _i.OS and the first amplitude difference A _1.OS to the first harmonic and generates therefrom a first harmonic compensation signal 1.OKS.

The compensation signal generator 6 further comprises a summation device 9 which receives the fundamental vibration compensation signal GKS and the N harmonic compensation signals i.OKS and forms therefrom the compensation signal KS by means of addition.

6 shows a schematic block diagram of a third embodiment of the adaptation signal generator 5 and the compensation signal generator 6 of the broadband system 1 according to the present invention. The device after 6 differs from the device 5 in that the fundamental vibration compensation signal GKS and the N harmonic compensation signals i.OKS are selectively added to form the compensation signal KS. To reach the selectivity is between each tone generator 7 . 8-i and the summation device 9 one switch each 23 switched so that each compensation signal GKS, i.OKS can be selectively switched on.

Even though the present invention above based on preferred embodiments It is not limited to this, but in many ways and modifiable. For example, the broadband system according to the invention within an IVD solution (Integrated Voice Data System) or integrated in a DSLAM system be. Next are for generating the distance signal by the distance signal generator More options conceivable.

1

Broadband system

2

adaptation device

3

language system

4

Distance signal generator

5

Adaptation signal generator

6

Compensation signal generator

7

Grundschwingungstongenerator

8th

Oberschwingungstongenerator

8-i

i-th Oberschwingungstongenerator

9

Summing means

10

first subtraction

11

Fast Fourier transformer

12

Decider

13

second subtraction

14

first bandpass

15

second bandpass

16

Local exchange

17

separating filter

18

Local loop

19

Subscriber terminal

20

telephone device

21

Subscriber line interface circuit

22

ADC

23

switch

KS

compensation signal

eBS

received Broadband signal

detBS

detected Broadband signal

verSS

reinforced sinusoidal

signaling signal

eBS + verSS

layered received broadband signal

FEBS

error compensated received wideband sig

nal

feBS _fft

Fourier-transformed error compensated

received Broadband signal

DS

distance signal

AS

adaptation signal

φ _GS

phase difference to the fundamental

A _GS

amplitude difference to the fundamental

Y _i.os

phase difference to the ith harmonic

A _i.os

amplitude difference to the i-th

harmonic

DG

Fundamental distance

OD

Harmonic distance

DPS

speech signal

GKS

Fundamental compensation signal

i.OKS

i-th Harmonic compensation signal

Claims (15)

Broadband system ( 1 ) for transmitting and receiving broadband signals with an integrated adaptation device ( 2 ), which receives a compensation signal (KS) from the received broadband signal (eBS), which is amplified with a sinusoidal signaling signal (verSS) and a wideband system ( 1 ) couplable speech system ( 3 ) is superimposed, adaptively generated and the generated compensation signal (KS) from the superimposed received wideband signal (eBS + verSS) subtra so that an error-compensated received wideband signal (feBS) is formed. Broadband system according to claim 1, characterized in that the adaptation device ( 2 ) a distance signal generator ( 4 ), which generates from the error-compensated received wideband signal (feBS) a distance signal (DS) which is characterized by a harmonic distance (OD) between the superimposed received wideband signal (eBS + verSS) and a detected noise-free wideband signal (detBS) and by a fundamental oscillation distance (GD ) between the fundamental of the amplified sinusoidal signaling signal (verSS) and the signaling signal (SS) is formed. Broadband system according to one or more of the preceding claims, characterized in that the adaptation device ( 2 ) an adaptation signal generator ( 5 ), which generates from the distance signal (DS) an adaptation signal (AS) consisting of a phase difference (φ _GS ) and an amplitude difference (A _GS ) of the fundamental and N phase differences (φ _i.OS ) and N amplitude differences (A _{i .OS} ) of the harmonics of the amplified sinusförmi signaling signal (verSS) and the sinusoidal signaling signal (SS) consists. Broadband system according to one or more of the preceding claims, characterized in that the adaptation device ( 2 ) a compensation signal generator ( 6 ), which generates the compensation signal (KS) by means of the adaptation signal (AS). Broadband system according to one or more of the preceding claims, characterized in that the compensation signal generator ( 6 ) a fundamental vibration sound generator ( 7 ) which receives the phase difference (φcs) and the amplitude difference (A _GS ) of the fundamental and generates therefrom a fundamental vibration compensation signal (GKS). Broadband system according to one or more of the preceding claims, characterized in that the compensation signal generator ( 6 ) N harmonic tone generators ( 8th ), wherein the i-th harmonic _{tone generator} (8-i) _receives the i-th phase difference (φ _i.OS ) and the i-th amplitude _difference (A _i.OS ) at the i-th harmonic and _{obtains it} i th Harmonic compensation signal (i.OKS) generated. Broadband system according to one or more of the preceding claims, characterized in that the compensation signal generator ( 6 ) a summation device ( 9 ), which selectively adds the fundamental vibration compensation signal (GKS) and the N harmonic compensation signals (i.OKS) to form the compensation signal (KS). Broadband system according to one or more of the preceding claims, characterized in that the adaptation device ( 2 ) a first subtraction device ( 10 ), which subtracts the generated compensation signal (KS) from the superimposed received wideband signal (eBS + verSS). Broadband system according to one or more of the preceding claims, characterized in that the distance signal generator ( 4 ) a fast Fourier transformer ( 11 ), which transforms the error-compensated received broadband signal (feBS) into a Fourier-transformed error-compensated received wideband signal ( _feBSfft ). Broadband system according to one or more of the preceding claims, characterized in that the fundamental oscillation _distance (GD) is formed from the coefficient for the fundamental of the Fourier-transformed error-compensated received wideband signal (feBS _fft ). Broadband system according to one or more of the preceding claims, characterized in that the distance signal generator ( 4 ) a decision-making device ( 12 ), which _decides on the noise-free wideband signal (detBS) by means of the Fourier-transformed error-compensated received wideband signal (feBS _fft ). Broadband system according to one or more of the preceding claims, characterized in that the distance signal generator ( 4 ) a second subtraction device ( 13 ), which calculates the harmonic _{distortion distance} (OD) from the difference between the noise-free detected wideband signal (detBS) and the Fourier-transformed error-compensated received broadband signal ( _feBSfft ). Broadband system according to one or more of the preceding claims, characterized in that the distance signal generator ( 4 ) a first bandpass ( 14 ) which bandpass filters the error-compensated received wideband signal (feBS) such that the distance signal generator ( 4 ) provides the fundamental swing distance (GD) from the bandpass filtered error compensated received wideband signal (feBS). Broadband system according to one or more of the preceding claims, characterized in that the distance signal generator ( 4 ) N second bandpasses ( 15 ), which is the error-compensated each received wideband signal (feBS) each such bandpass filters, so that the distance signal generator ( 4 ) provides the harmonic distortion (OD) from the bandpass filtered error-compensated received wideband signal (feBS). Local exchange ( 16 ) with a broadband system ( 1 ) according to any one of the preceding claims; with a separating filter ( 17 ) which the broadband system ( 1 ) and a language system ( 3 ) such that wideband signals of the broadband system ( 1 ) and speech signals (SpS) of the speech system ( 3 ) on a single subscriber line ( 18 ) are transferable.