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EP1284074A2 - Dispositif et procede permettant de verifier si un signal a ete recu a une frequence definie - Google Patents

Dispositif et procede permettant de verifier si un signal a ete recu a une frequence definie

Info

Publication number
EP1284074A2
EP1284074A2 EP01947312A EP01947312A EP1284074A2 EP 1284074 A2 EP1284074 A2 EP 1284074A2 EP 01947312 A EP01947312 A EP 01947312A EP 01947312 A EP01947312 A EP 01947312A EP 1284074 A2 EP1284074 A2 EP 1284074A2
Authority
EP
European Patent Office
Prior art keywords
signal
received
predetermined frequency
comparison
frequency
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP01947312A
Other languages
German (de)
English (en)
Inventor
Peter Pessl
Christian Schranz
Alessandro Fulli
Michael Staber
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Infineon Technologies AG
Original Assignee
Infineon Technologies AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Infineon Technologies AG filed Critical Infineon Technologies AG
Publication of EP1284074A2 publication Critical patent/EP1284074A2/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/18—Electrical details
    • H04Q1/20—Testing circuits or apparatus; Circuits or apparatus for detecting, indicating, or signalling faults or troubles
    • H04Q1/22—Automatic arrangements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/10—Frequency-modulated carrier systems, i.e. using frequency-shift keying
    • H04L27/14—Demodulator circuits; Receiver circuits
    • H04L27/156—Demodulator circuits; Receiver circuits with demodulation using temporal properties of the received signal, e.g. detecting pulse width
    • H04L27/1563—Demodulator circuits; Receiver circuits with demodulation using temporal properties of the received signal, e.g. detecting pulse width using transition or level detection

Definitions

  • the present invention relates to a device according to the preamble of claims 1, 5 and 7, and a method according to the preamble of claims 15, 16 and 17, i.e. an apparatus and a method for checking whether a signal is received at a predetermined frequency.
  • Such a device and such a method are required, for example, in the case of the so-called "splitterless integrated voice and data linecard".
  • Splitterless integrated voice and data linecards are electrical printed circuit boards which are used in telecommunications switching centers (hereinafter referred to as central offices). It is up to you
  • telecommunications subscribers receive voice data received from telecommunications subscribers (hereinafter referred to as clients), identify them as voice data, convert them into PCM-coded data, and forward them, and
  • client modem XDSL modem present at the client
  • ATM-coded data implement and forward.
  • splitterless integrated voice and data line cards can be designed differently.
  • the presently contemplated splitterless integrated voice and data line card is a Li-te version that is standardized in ITU G.lite '.
  • ITU G.lite allows parts of the splitterless integrated voice and data linecard to be put into an energy-saving mode in which they require significantly less energy than in normal operation.
  • ITU G.lite defines a so-called wake-up sequence. Accordingly, the splitterless integrated voice and data linecard must be switched from the energy-saving mode to the normal mode if it receives a signal from the client modem with a certain maximum power and one of three defined frequencies.
  • a particular problem here is checking whether a signal is received at one of the frequencies at which the splitterless integrated voice and data linecard has to be reset to the normal operating mode.
  • the line between the client modem and the Central Office, over which the wake-up signal is to be transmitted can be any length of line, and -, consequently one can have very high attenuation (e.g. an approx. 4 km long line can already have approx. -60 dB attenuation),
  • the transmission of the wake-up signal can be disturbed by noise and by crosstalk
  • the wake-up signal may have to pass parts of the splitterless integrated voice and data linecard which are in the energy-saving mode, as a result of which the wake-up signal does not arrive at full power at the device which has to check whether a wake-up signal is received.
  • the present invention is therefore based on the object of finding a device and a method by which it can be reliably checked with little effort whether a signal with a predetermined frequency is received.
  • the devices and methods according to the invention are characterized in that - • that the received signal or one on the received
  • Signal-based signal is compared with one or more threshold values
  • the device decides, depending on the result of this comparison, whether or not a signal with the predetermined frequency is received (device according to claim 1), or
  • a determination result sequence comparison device which compares the sequence of determination results obtained in the repeated determination with one or more predetermined determination result sequences
  • That the device decides, depending on the result of this comparison, whether or not a signal with the predetermined frequency is received
  • That a control device which, in the event that a signal is apparently received at a frequency which is substantially higher than the predetermined frequency, changes the device by means of which the noise signal level and / or its influence on the one to be undertaken Check are reduced (device according to claim 7), or
  • the claimed devices and the devices required to carry out the claimed methods can largely be implemented in digital technology, as a result of which they can be implemented in a relatively small and simple manner.
  • FIG. 1 shows a first device for checking whether a signal 'having a predetermined frequency is received
  • Figure 2 shows a second device for checking whether a signal is received at a predetermined frequency
  • FIG. 3 shows a third device for checking whether a signal is received at a predetermined frequency
  • FIG. 1 shows a first exemplary embodiment of a device which can be used to check whether a signal is currently being received at a predetermined frequency.
  • the signal with the predetermined frequency is the wake-up signal, which the client modem outputs if necessary, in order to return at least parts of the splitterless integrated voice and data linecard from the energy-saving mode to the normal mode.
  • the wake-up signal WUS first arrives in a bandpass filter BPF.
  • the bandpass filter BPF more precisely the position of the frequency band that is passed through it, can be set via a control connection fOselect.
  • three different frequency bands can be set. The different frequency bands are selected such that either a wake-up signal having the first wake-up frequency, or a wake-up signal having the second wake-up frequency, or a third wake-up signal Frequency-bearing wake-up signal can be passed.
  • the output signal of the bandpass filter BPF is fed to an amplifier AMP. This amplifies the signal fed to it.
  • the output signal of the amplifier AMP is fed to a high-pass filter HPF. This is provided in order to filter out the noise generated in the amplifier AMP, in particular the so-called flicker noise component.
  • the said flicker noise component is so strongly attenuated by the high-pass filter HPF that it has no particular influence on the further processing of the signal.
  • the HPF high-pass filter also eliminates any offset that may be present.
  • the output signal of the high-pass filter HPF is fed to a comparator COMP.
  • the comparator COMP works with a hysteresis. That .
  • the comparator COMP outputs an output signal with a first level when the potential of the signal fed to it exceeds a first (upper) threshold value and maintains this state until the potential of the signal fed to it falls below a second (lower) threshold value , and
  • the comparator COMP outputs an output signal with a second level when the potential of the signal fed to it falls below the second - (lower) threshold value, and maintains this state until the potential of the signal fed to it exceeds the first (upper) threshold value.
  • the threshold values are set in such a way that the noise which is still contained in the signal supplied to the comparator COMP cannot cause a switchover of the output signal of the comparator COMP, that is to say the threshold values are above and below the noise signal level. If the device shown in FIG. 1 is supplied with a signal WUS having one of the wake-up frequencies, and the bandpass filter
  • BPF allows this signal to pass, there is a wake-up frequency at the output of the comparator COMP. send square wave signal; If the device is supplied with a signal with a frequency that is not passed by the bandpass filter BPF, or if no signal is supplied to the device, the output signal of the comparator COMP remains permanently at level 0 or level 1.
  • the output signal of the comparator COMP is fed via a switch S to a counter COUNT and triggers it.
  • the counter COUNT thus counts the number of changes in the output signal of the comparator COMP from low to high level (or the number of changes in the output signal of comparator COMP from high to low level).
  • the counting frequency thus corresponds to the frequency of the wake-up signal WUS.
  • the counter COUNT can "only" count if and as long as the switch S is closed; if the switch S is open, the counter does not receive a trigger signal which causes it to count up.
  • the switch S is normally open and is only closed for a specific time. Before the switch S is closed, the counter is reset by applying a corresponding signal to a reset connection reset thereof. If the switch S is then closed for the predetermined time, the counter counts during this time with a counting frequency corresponding to the frequency of the wake-up signal WUS. Counting ends when switch S is opened.
  • the count reached after opening the switch S is fed to a comparison device CU which compares it with one or more values which are stored in a look-up table provided in the comparison device or elsewhere.
  • the values stored in the look-up table are selected so that if the count of the counter COUNT matches one of these values, that a wake-up signal having a wake-up frequency is received.
  • the comparison device CU and / or the look-up table have a control connection, not shown in FIG. 1, via which it is possible to set, with which value or with which values the count of the counter COUNT is to be compared. These values are different for the different wake-up frequencies. Alternatively, it can be provided that the switch S is closed depending on the wake-up frequency for which the received signal is currently being examined, so long that the same count results for all wake-up frequencies.
  • the comparison device CU outputs a signal representing the result of the comparison. At the same time, this signal signals whether a wake-up signal having one of the wake-up frequencies is being received, and can be considered a OJ OJ t MF 1 F 1
  • the device shown in FIG. 2 is distinguished from the device shown in FIG. 1 in that the decision as to whether or not a signal having one of the wake-up frequencies is received is based on a more or less long sequence of results takes place, which are obtained in a repeated determination as in the device according to FIG. 1 or carried out differently as to whether a signal having one of the wake-up frequencies is received or not.
  • the device shown in FIG. 2 completely contains the device shown in FIG. 1 and described with reference to it, but additionally has a digital evaluation logic (provided behind the comparison device CU); in the example under consideration, this digital evaluation logic consists of a shift register SR and a second comparison device (a determination result sequence comparison device) CU2.
  • the output signal of the comparison device CU is not already used as the output signal of the device. Instead, it is decided (by the shift register SR and the second comparison device CU2) depending on the course of the output signal of the comparison device CU whether a signal having one of the wake-up frequencies is being received.
  • the output signal of the comparison device CU is fed to the shift register SR, and transferred to it with a clock clock and pushed on.
  • the clock clock preferably has the same frequency as the signal used to control the switch S.
  • the time course of the output signal of the comparison device CU is recorded in the shift register SR.
  • the content of the shift register SR is fed to the second comparison device CU2 and in this with one or a plurality of reference bit patterns refpat also supplied to the second comparison device CU2 are compared.
  • the second comparison device CU2 has a control connection via which it is possible to set, with which reference bit pattern or with which reference bit pattern the content of the shift register is to be compared.
  • the signal fOselect controlling the bandpass filter BPF can be applied to this control connection. This is necessary because the data contained in the shift register SR are the result of successive different checks; Depending on the frequency, the reception of which is to be checked by the second comparison device CU2, different reference bit patterns refpat must be used.
  • the comparison device CU2 outputs a signal representing the result of the comparison. This signal also signals whether a wake-up signal having one of the wake-up frequencies is being received and can therefore be used as the wake-up bit WUB, which sets the energy-saving mode back Parts of the splitterless integrated voice and data linecard are put into normal operating mode.
  • the reference bit patterns are selected in such a way that it is only decided that a signal having one of the wake-up frequencies is received if this is done by the comparison device CU a predetermined number of times in succession and / or a predetermined number of times within one predetermined period of time was determined.
  • the device shown in FIG. 2 and described with reference to it for checking whether a signal is received at a predetermined frequency thus works even more reliably than the device shown in FIG. 1 and described with reference to it.
  • the device shown in FIG. 3 contains the device shown in FIG. 2 and described with reference to FIGS. 1 and 2, but additionally has a digital adaptation logic which adjusts the amplifier AMP taking into account the given conditions so that the checking, whether a wake-up signal is received, can under no circumstances be disturbed by noise or other interference;
  • this digital adaptation logic consists of a memory device formed by a flip-flop FF in the present case and a gain setting device AMPCTL.
  • the flip-flop FF is connected to a terminal OV indicating an overflow of the counter COUNT. It temporarily stores the meter's connection OV
  • the gain setting device AMPCTL causes one depending on the value of the signal supplied to it by the flip-flop FF
  • the output signal of the comparator changes so often that the counter COUNT triggered by this signal overflows within the time during which the switch S is closed.
  • the prerequisite for this is, of course, that a counter is used, the maximum count of which is not very much higher than the count which is reached when an undisturbed signal having one of the wake-up frequencies is supplied to the comparator, or that a counter is used which overflows when a signal having a noise signal level exceeding the comparator thresholds is supplied to the comparator; the provision of such a counter has no negative effects on the function and the feasibility of the device and can therefore be carried out without problems.
  • the overflow of the counter COUNT is a clear indication that the signal fed to the comparator COMP has so much noise that it is no longer possible to reliably detect a signal having one of the wake-up frequencies.
  • the noise of the signal fed to the comparator COMP can be reduced by reducing the amplification factor of the amplifier AMP.
  • a lower amplification factor means that the noise component contained in the signal supplied to the splitterless integrated voice and data linecard is less amplified, and moreover an amplifier AMP that amplifies with a lower amplification factor itself generates less noise.
  • a setting of the gain factor of the gain dependent on the count of the counter COUNT. kers AMP is therefore a very simple, yet highly effective way of setting the amplifier's amplification factor to the ideal value.
  • a first possibility is that the amplification factor of the amplifier AMP is first set to the maximum value. If the noise signal level is too high, the COUNT counter overflows. This causes the gain adjuster AMPCTL to reduce the gain. If the counter then overflows again (with the reduced amplification factor), the amplification setting device AMPCTL reduces the amplification factor again. This process is repeated until an amplification factor setting has been reached at which the counter no longer overflows. This gain setting, or a gain setting reduced by one or more steps for safety's sake, is then the ideal gain setting that is preferably used in checking whether a signal is received at a predetermined frequency and the most reliable results supplies.
  • the determination and setting of the optimal amplification factor can also be carried out any other way than described above.
  • the size and / or the number of stages in which the amplification factor is changed can, among other things, be determined and / or varied as desired.
  • the amplifier AMP has a plurality of amplifier stages, the amplification factors of which can be changed in stages of different sizes.
  • the amplifier AMP comprises two ner amplifier stages, designated by the reference numerals AMP1 and AMP2 in FIG. 3, the amplification factor of the first amplifier stage AMP1 being changeable in large steps, and the amplification factor of the second amplifier stage AMP2 being changeable in comparatively small steps.
  • a gain factor setting as described or in a different way enables the splitterless integrated voice and data linecard to be optimally adapted to the particular circumstances, in particular the length of the line between the client modem and the central office (attenuation) and the existing interference adapt.
  • the overflow of the COU ⁇ T counter does not necessarily have to be used as the triggering event for the measures described.
  • reaching or exceeding a certain other count can be used as the triggering event.
  • Reaching or exceeding the specific count can be detected by monitoring the count output by the counter or selected (preferably the most significant) bits thereof.
  • the same result or a similar result can be achieved if, depending on the count reached in the counter or other parameters providing information about the noise signal level or other disruptive influences, additionally or alternatively on the bandpass filter BPF, the high-pass filter HPF and / or the comparator (for example on the threshold values used by this) is influenced.
  • the device described also provides information about which of the frequencies to be detected has the received signal. This information can also be obtained from the described
  • the comparison devices CU and CU2 can - if necessary taking into account the current or previous value of the control signal fOselect - recognize from the comparison result (from the knowledge in which of the comparisons to be carried out there was a match) which of the frequencies to be detected the received signal having.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Telephonic Communication Services (AREA)
  • Monitoring And Testing Of Transmission In General (AREA)
  • Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
  • Telephone Function (AREA)
  • Measuring Frequencies, Analyzing Spectra (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
  • Selective Calling Equipment (AREA)

Abstract

L'invention concerne un dispositif et un procédé, dans lesquels la détermination de fréquence normalement très coûteuse et compliquée est effectuée par le biais de mesures très simple à élaborer et à mettre en oeuvre, notamment par des comparaisons 'supérieur, inférieur et/ou égal à' et par un comptage d'événements spécifiques. L'invention concerne également des agencements par lesquels le niveau de bruit du signal ou son influence sur la vérification à effectuer peuvent être réduits.
EP01947312A 2000-05-24 2001-05-23 Dispositif et procede permettant de verifier si un signal a ete recu a une frequence definie Withdrawn EP1284074A2 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10025581 2000-05-24
DE10025581A DE10025581A1 (de) 2000-05-24 2000-05-24 Vorrichtung und Verfahren zur Überprüfung, ob ein Signal mit einer vorbestimmten Frequenz empfangen wird
PCT/EP2001/005938 WO2001091309A2 (fr) 2000-05-24 2001-05-23 Dispositif et procede permettant de verifier si un signal a ete recu a une frequence definie

Publications (1)

Publication Number Publication Date
EP1284074A2 true EP1284074A2 (fr) 2003-02-19

Family

ID=7643301

Family Applications (1)

Application Number Title Priority Date Filing Date
EP01947312A Withdrawn EP1284074A2 (fr) 2000-05-24 2001-05-23 Dispositif et procede permettant de verifier si un signal a ete recu a une frequence definie

Country Status (7)

Country Link
US (1) US7224751B2 (fr)
EP (1) EP1284074A2 (fr)
JP (1) JP2003534702A (fr)
KR (1) KR100559934B1 (fr)
CN (1) CN1168270C (fr)
DE (1) DE10025581A1 (fr)
WO (1) WO2001091309A2 (fr)

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TW595128B (en) * 2002-04-09 2004-06-21 Mstar Semiconductor Inc Radio frequency data communication device in CMOS process
AT413251B (de) 2003-12-09 2005-12-15 Efkon Ag Aufwecksignal-detektorschaltung
DE102007029660B4 (de) * 2007-06-27 2011-06-01 Vega Grieshaber Kg Adaptiver Fehlerzähler für ein drahtloses Feldgerät
US7848363B2 (en) * 2008-05-15 2010-12-07 Motorola, Inc. System and method for receiving call signals in a communication system
US9922733B2 (en) * 2009-11-06 2018-03-20 Terrapower, Llc Methods and systems for migrating fuel assemblies in a nuclear fission reactor
JP4977239B2 (ja) * 2010-06-30 2012-07-18 株式会社東芝 無線通信装置
CN102468821B (zh) * 2010-11-16 2014-07-30 博通集成电路（上海）有限公司 唤醒电路、车载单元、滤波器以及频率探测和过滤的方法
CN116667858B (zh) * 2023-08-01 2023-10-27 上海芯炽科技集团有限公司 一种用于检测mipi aphy高速差分信号的方法

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Also Published As

Publication number Publication date
WO2001091309A2 (fr) 2001-11-29
US7224751B2 (en) 2007-05-29
CN1168270C (zh) 2004-09-22
CN1430843A (zh) 2003-07-16
DE10025581A1 (de) 2001-12-13
US20030179822A1 (en) 2003-09-25
WO2001091309A3 (fr) 2002-07-11
KR100559934B1 (ko) 2006-03-13
KR20030003756A (ko) 2003-01-10
JP2003534702A (ja) 2003-11-18

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