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WO1992003887A1 - Systeme d'amplificateur modulaire pour la distribution de signaux de television - Google Patents

Systeme d'amplificateur modulaire pour la distribution de signaux de television Download PDF

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Publication number
WO1992003887A1
WO1992003887A1 PCT/AU1991/000385 AU9100385W WO9203887A1 WO 1992003887 A1 WO1992003887 A1 WO 1992003887A1 AU 9100385 W AU9100385 W AU 9100385W WO 9203887 A1 WO9203887 A1 WO 9203887A1
Authority
WO
WIPO (PCT)
Prior art keywords
signal
combining apparatus
module
connection
signal combining
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.)
Ceased
Application number
PCT/AU1991/000385
Other languages
English (en)
Inventor
Jan Raubiszko
Robert John Richards
Donald West
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.)
Hills Health Pty Ltd
Original Assignee
Hills Industries Ltd
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 Hills Industries Ltd filed Critical Hills Industries Ltd
Publication of WO1992003887A1 publication Critical patent/WO1992003887A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00—Auxiliary devices
    • H01P1/20—Frequency-selective devices, e.g. filters
    • H01P1/201—Filters for transverse electromagnetic waves
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00—Auxiliary devices
    • H01P1/04—Fixed joints
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N7/00—Television systems
    • H04N7/10—Adaptations for transmission by electrical cable
    • H04N7/102—Circuits therefor, e.g. noise reducers, equalisers, amplifiers
    • H04N7/104—Switchers or splitters
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/14—Structural association of two or more printed circuits
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K7/00—Constructional details common to different types of electric apparatus
    • H05K7/14—Mounting supporting structure in casing or on frame or rack
    • H05K7/1438—Back panels or connecting means therefor; Terminals; Coding means to avoid wrong insertion
    • H05K7/1439—Back panel mother boards
    • H05K7/1441—Back panel mother boards with a segmented structure
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/0213—Electrical arrangements not otherwise provided for
    • H05K1/0237—High frequency adaptations
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
    • H05K2201/10—Details of components or other objects attached to or integrated in a printed circuit board
    • H05K2201/10227—Other objects, e.g. metallic pieces
    • H05K2201/10325—Sockets, i.e. female type connectors comprising metallic connector elements integrated in, or bonded to a common dielectric support

Definitions

  • This invention relates to radio and television signal distribution systems and in particular a modular receiver and amplifier system for the simultaneous distribution of radio and television signals to a number of receivers, and in particular a signal combining means which is integral with the modular components of the distribution system.
  • television and radio signals for distribution to a large number of users within a building are received off air by antennas specifically designed to provide low noise, low interference, and minimum multipath distortion which otherwise is not obtainable or desirable at each of the user's locations within the building.
  • antennas specifically designed to provide low noise, low interference, and minimum multipath distortion which otherwise is not obtainable or desirable at each of the user's locations within the building.
  • lodging establishments such as hotels and motels prefer to utilise a single television reception antenna and its associated television distribution system so that a multiplicity of television receivers located in each of the rooms of the establishment may be supplied with adequate television and radio signals in addition to providing produced video programming controlled by the establishment.
  • the typical elements of such systems comprise: an antenna, with which MW radio, VHF and UHF television broadcast signals are received; a signal processing and combining module; a distribution system used to distribute the combined signals to subscribers or individual television receivers located in each of the rooms of the establishment and standard radio and television receivers which are fed signals from the distribution system.
  • signal processing and combining modules comprise antenna pre-amplifiers, AM and FM hetrodyne repeaters, single channel amplifiers, UHF and VHF to IF down converters, IF to VHF and UHF up converters, vestigial sideband audio/video modulators and the associated mixing networks required to combine the individual outputs of various program sources to feed the distribution system.
  • the signal processing and combining modules are usually located close to the antenna where it is possible to receive the desired off air channels with a minimum of interference and at a sufficiently high level to obtain a high quality starting signal for combination and eventual distribution by the system.
  • the signal processing and combining modules are interconnected with a complex array of radio frequency coaxial cables and various other signal and power carrying wires.
  • the radio frequency signal combining modules it is known for the radio frequency signal combining modules to use pre-cut coaxial cable interconnections between units, so as to maximise signal coupling efficiencies between the processing and combining equipment. It is therefore important for installation and service personnel to maintain the correct interconnection arrangement and to not unduly interfere with the critical length of the coaxial cables thereof.
  • MTBF Mean Time Between Failure
  • each element of a signal distribution system is required to be connected to another element of the system and a large number of cables and wires is required to achieve this.
  • Such an arrangement can be a difficult environment in which to trace a fault and it is a desirable requirement of such a system to have a signal combining device between signal processing modules which eliminates the need for a complicated array of interconnecting cables.
  • each element should ideally be capable of being monitored and modules replaced by untrained and unskilled users with minimum potential of disturbance to the combining device, so that simple faults may be easily identified and rectified prior to the attendance of repair personnel.
  • Another aspect of the invention comprises a frequency conversion system integrated within a module and its adjacent module, such that physical interconnection between the modules when located adjacent each other and interconnected via integral connection means allows a I.F. frequency selective amplifier in one module and working with a dual frequency conversion sub-system in another module to have a common output. This common output may then be combined into the radio frequency to be distributed through the system.
  • Fig. 1 depicts the front panel layout of a modular television signal distribution system
  • Fig. 2 depicts a top perspective view of two connected circuit boards of the modular television signal distribution system and details in particular the configuration of the radio frequency connector used for connecting the modules together;
  • Fig. 3 depicts a sectional view of one half of the casing of a television signal distribution system module
  • Fig. 4 depicts a sectional view of the casing of the other half of a television signal distribution system module orientated for fitment with the half depicted in Fig. 3;
  • Fig. 5 depicts a schematic representation of the radio frequency combiner configuration of the television signal distribution system
  • Fig. 6 depicts a schematic representation of the insertion loss of an embodiment of the signal combiner configuration
  • Fig. 7 is a schematic representation of a helical filter element
  • Fig. 8 shows a bottom view of an arrangement for varying the matching impedance of a tuning element
  • Fig. 9. shows an arrangement for varying the coupling efficiency of closely coupled tuning elements.
  • Fig. 1 a typical configuration of modules of a television signal distribution system.
  • Rack members 10 and 11 are spaced apart and fixed to a stable wall surface parallel to one another. Their cross-sectional profile is such as to allow reciprocally shaped guide members fixed to the top and bottom rear wall of each module to slidably engage with the rack member and be releasably fixable and locatable along the members 10 and 11.
  • the power supply module 12 is locatable adjacent module 13 which is a VHF Channel 10 receiver/amplifier as per the Australian Broadcasting Band Plan.
  • Reciprocal connectors 19 and 20 located at their lower ends and on opposing sides are releasably connectable to each other. Radio frequency and Intermediate Frequencies (IF) and power are connected between modules.
  • IF Intermediate Frequencies
  • Power supply module 12 also has a radio frequency signal output connector 21 to which is connected a signal distribution system, typically a low loss coaxial cable 22 which is taped off and terminated as required in the vicinity of individual television receivers.
  • a signal distribution system typically a low loss coaxial cable 22 which is taped off and terminated as required in the vicinity of individual television receivers.
  • the arrangement of modules depicted in this embodiment comprises individual VHF receiver modules 13-16 for channels 10, 9, 7 and 2 respectively of the Australian Broadcasting Band Plan and a UHF to IF down converter module 18 for channel 28 of the same plan which is located adjacent an IF to VHF up converter module 17 for channel 0 of the same plan.
  • Connector 35 shown on the opposite side of module 18 to connector 33 may be used to append to the configuration addition modules, for example, pre-amplifiers for weak received antenna signals, vestigial sideband modulators for audio/video input and other like modules.
  • a UHF antenna 23 is connected to the RF input 24, while a VHF Band II antenna 25 of the plan is connected to the RF input 26 of module 16 and a VHF Band III antenna 27 is connected to a passive splitter (but which may also be an active splitter) 28 which in turn is connected to the RF inputs 29, 30 and 31 of modules 13, 14 and 15 respectively.
  • connectors between the modules provide a continuous path for radio frequency and power distribution between modules.
  • To isolate a module for replacement its guide members are loosened so that the modules may move laterally along the rack members 10 and 11 towards their left or right. Further lateral movement of the desired module, releases its connector from the adjacent module. Having isolated the module the guide member allows the module to be raised and removed from engagement with the rack members. Replacement with a repaired or new module is achieved by reversing the above process .
  • This method of module interconnection ensures constant standard of conduction between elements of the conductor and obviates the need for an untidy collection of pre-cut coaxial cable interconnection means between modules.
  • Fig. 2 depicts one embodiment of connectors 34-37 which comprise DB15 connectors, wherein connectors 35 and 36 are plugs and 34 and 37 are sockets.
  • Printed circuit board 38 associated with module 18 and printed circuit board 39 associated with module 19 carry on their lower sides, a track 40 for conducting direct current power and a track 41 for conducting radio frequency signals.
  • Larger surface area tracks 41, 42 and 43 are connected to earth as are the substantially unbroken conductive upper surfaces 44 and 44a (not shown) of the boards 38 and 39 and form in this embodiment a printed-board strip line (microstrip) in combination with track 41 which is particularly suited for the transmission of radio frequencies.
  • Coaxial cable 47 carries VHF radio frequency channel 0 from the output of the up converter circuit of module 17 and is connected to track 40 on printed circuit 39.
  • the output circuit of module 17 may comprise a variety of matching and combining means, in this embodiment a capacitive coupling circuit is used.
  • Fig. 5 schematically depicts a variety of coupling means including inductive means.
  • the characteristic impedance, attenuation of microstrip 40 on printed circuit board 38 is dependant on the spacing between track 40 and its adjacent tracks 41 and 42 and the conductive surface 45 as well as the thickness of track 40 and the frequency of the signal being transmitted. Additionally, since the printed circuit board 38 is located at the lower portion of the module and track 40 faces the bottom metallic cover of the module a further RF barrier is created which isolates the transmission path created by the microstrip from the active circuit within the module and the effects of external radio frequency noise.
  • the signal strip 40 is etched to the appropriate size to provide the required impedance and attenuation performance, while the ground usually covers the opposite side of the printed circuit board, but is required only to be at least twice as wide as the signal strip.
  • Copper is the commonly used conductor material and the performance of icrostrips, like other high frequency signal-carrying transmission line devices, is very much dependant on the characteristics of the dielectric material between the conductor material.
  • plastics such as pure plastic, filled plastic, and fibre-reinforced plastic present some alternative materials.
  • other factors are important such as heat dissipation and its variation with frequency and temperature, homogeneity, uniformity and isotropy, useful temperature range, dimensional stability, tensile and flexural strength and processing limitations.
  • the rigid physical configuration of the interconnections created by the connectors located as shown in Figs. 1 and 2 provides for an equally spaced arrangement of modules and thereby a constant spacing relationship between the physical location of the radio frequency combining elements. This is advantageous for the optimum transfer of the received signal onto the transmission path created by the in-line radio frequency connectors .
  • Figs . 3 and 4 show sectional views of the profile of identical halves of an extruded metallic casing for the modular circuit boards previously described.
  • the module enclosure comprises two identical halves which are assembled face to face to form a hollow rectangular housing.
  • the top half of a casing depicted in Fig. 3 comprises side walls 49 and 50 at right angles to each other joining along a reinforcing rib 68.
  • the free edge 51 of side wall 49 is designed to snugly fit in grooved edge 56.
  • An identical grooved marginal portion 52 on the other half, shown in Fig. 4 similarly receives the edge 57 of the first half.
  • Ribs 64 and 65 on side 54 align in opposed relationship with ribs 66 and 67 on circuit board runner 59 when the structure is in its closed configuration.
  • End caps (not shown) are used to seal the structure and screws are inserted through the end caps and into the grooves between ribs 64, 65 and 66, 67 wherein the peripheral edge of the helical screw contacts and frictionally engages both pairs of ribs .
  • This arrangement provides further electrical connection between the parts of the housing obviating the need for separate straps and/or links to be provided while improving the radio frequency sealing of the constructed housing.
  • ribs 70, 71 are opposed to ribs 62, 63 when the sides are brought together.
  • Circuit board runner lugs 58 and 60 are also opposed to each other when the sides are brought together and allow sliding insertion and/or retention of the circuit board or removal of the side frame to provide access to the circuits therein.
  • circuit board opposed runner lugs 59 and 61 are similarly available for supporting a circuit board therein when the sides are brought together.
  • Fig. 5 shows a schematic representation of the signal combiner network configuration which results from the spaced relationship of the radio frequency connectors which are in ⁇ line along the base of the modular TV signal distribution system and which terminate into the distribution cable 22.
  • a nominal mid-band frequency for the transmission line is determined and the spaced relationship of the radio frequency combiners is a combination of capacitive and inductive coupling devices which are arranged along the transmission line to maximise signal transfer efficiency as a result of their location along that transmission line.
  • a purely resistive 75 ohm or as desired value of the termination load may be located at an end of the combiner transmission line network 40.
  • a capacitively coupled radio frequency source 1 is located adjacent an inductively coupled radio frequency source 2. It will be apparent that the modules which relate to source 1 and 2 respectively are located at fixed distances from the termination point by virtue of the fixed spaced relationship of the connectors and the location of the combining units therebetween when incorporated in the modular system described in Fig. 1.
  • a radio frequency source 3 which is capacitively coupled to the combiner transmission line network.
  • a termination impedance of greater .value than the impedance of the transmission line allows a capacitive coupling to see low impedance at the termination point and conductively coupled sources effectively have an open circuit coupling at their locations .
  • Radio frequency source 3 is shown as an IF source which is conducted to an adjacent module for further signal processing whereby radio frequency source 5 is capacitively coupled to the combiner/transmission line network.
  • a nominal direct current conduction path 39 is also depicted in Fig. 5, while earth 63 is depicted pictorially above and below the combiner/transmission line network 40.
  • Fig. 6 depicts the insertion loss characteristics of the combiner/transmission line which has six channels (2, 7, 9, 10, 28 and 52) impressed upon it.
  • the vertical axis depicts loss in lO.OdBuV per graduation while the horizontal axis depicts frequency in 100MHz per graduation.
  • Fig. 7 depicts a pictorial section view of a helical filter element.
  • These filters commonly comprise a helically wound coil located within a radio frequency sealed can- shaped encapsulation 90.
  • the coil may have a high Q value and is shown as having a free end 110 located in close proximity to the inner surface of the can 111 and which exhibits a small amount of capacitance between the coil and the can 90.
  • Helical filter coils of this general type generally have a separate earth connection 112, however some also have a preset tap 113 at which point radio frequency energy may be inserted into or extracted from the coil circuit element. This connection is preset and tuning of such coils is generally achieved by varying the longitudinal location of a metallic element 114 along the axis of the coil.
  • solder 97 or other conductor means may be used to bridge across from the extended coil portion 96 to earth and thus provide a convenient and otherwise unobtainable impedance matching mechanism and arrangement for such coil types .
  • Fig. 9 depicts an arrangement for varying the matching of closely coupled tuning elements.
  • the UHF modules of this device utilise helical filter elements.
  • can-shaped elements 90 and 91 are arranged adjacent one another.
  • One end of the coil within these cans is connected to a track of the printed circuit board 106 at node 92 as shown in Figs. 7 and 8.
  • the helical coil may then be shorted to the ground track 98 by providing a wire or other electrical connection link such as a solder bridge 97 to a suitable point from the circuit track 96 which forms part of the coil, so that suitable matching of the coil can be achieved.
  • Adjustment of the flap 103 in the directions of arrows 105 and 106 varies the degree of signal that may be coupled from one coil to the other. Coupling of the helical filters using this mechanical adjustment method has been found to be easy and convenient.
  • the flap 103 may be soldered permanently into position or alternatively if certain parameters have changed the flap may have its location relocated to adjust to the new parameters by adjusting its orientation and resoldering it into position.
  • An alternative arrangement for adjusting the coupling between helical filters is provided by soldering two thin and stiff wires upstanding between the adjacent cans 90 and 91.
  • the wires can then be moved into place to suit the required coupling between helical filter elements .

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  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Details Of Television Systems (AREA)

Abstract

Appareil combinant des signaux, particulièrement utile dans les systèmes de distribution de signaux de télévision, à conception modulaire, fournissant un moyen extensible et pratique d'ajouter et de remplacer des modules sans avoir à déconnecter de grandes quantités de câbles coaxiaux de longueur critique. Ledit appareil comprend des premier (35) et second (36) moyens de connexion situés sur les faces opposées d'un module (18) doté de dispositifs de connexion adaptés pour être connectés détachables à des modules adjacents (12, 17) selon les besoins. Ledit dispositif de transmission de signaux (40) est situé entre lesdits connecteurs et chaque module (12, 18) comporte un dispositif de traitement de signaux auquel est appliqué un signal de sortie et qui est doté d'un dispositif de combinaison de signaux (90) adapté de manière à apparier le dit signal de sortie au dispositif de transmission (40) et à le combiner avec un signal de ligne de transmission. La microbande est un exemple de dispositif de transmission approprié.
PCT/AU1991/000385 1990-08-23 1991-08-23 Systeme d'amplificateur modulaire pour la distribution de signaux de television Ceased WO1992003887A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AUPK188790 1990-08-23
AUPK1887 1990-08-23

Publications (1)

Publication Number Publication Date
WO1992003887A1 true WO1992003887A1 (fr) 1992-03-05

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ID=3774906

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/AU1991/000385 Ceased WO1992003887A1 (fr) 1990-08-23 1991-08-23 Systeme d'amplificateur modulaire pour la distribution de signaux de television

Country Status (1)

Country Link
WO (1) WO1992003887A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997015096A1 (fr) * 1995-10-18 1997-04-24 J.E. Thomas Specialties Limited Coupleur de sortie en sommet
US5675300A (en) * 1995-10-18 1997-10-07 J.E. Thomas Specialties Limited Top exit coupler
EP0838704A3 (fr) * 1996-10-24 1999-05-12 Nortel Networks Corporation Structures pour transmissions de données et relatives à des configurations de fond de panier pour données
US6039999A (en) * 1993-08-11 2000-03-21 Hunt Wesson, Inc. Reduced fat nut butter product and process for making the same
WO2019106497A1 (fr) * 2017-11-28 2019-06-06 Redox S.R.L. Système de communication modulaire multi-protocole
WO2020021043A1 (fr) * 2018-07-27 2020-01-30 International Business Machines Corporation Dispositif cryogénique à multiples lignes de transmission ayant un atténuateur de micro-ondes intégré

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU1315076A (en) * 1975-04-18 1977-10-27 Hochiki Co Signal. coupling and branching device
US4527136A (en) * 1983-02-15 1985-07-02 501 DX Antenna Company, Limited Signal coupling apparatus
US4612519A (en) * 1984-01-14 1986-09-16 Communications Patents Limited Switch assembly and circuit
US4618838A (en) * 1984-02-27 1986-10-21 Sony Corporation Impedance adjusting element for a microstrip circuit
US4816789A (en) * 1986-05-19 1989-03-28 United Technologies Corporation Solderless, pushdown connectors for RF and DC

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU1315076A (en) * 1975-04-18 1977-10-27 Hochiki Co Signal. coupling and branching device
US4527136A (en) * 1983-02-15 1985-07-02 501 DX Antenna Company, Limited Signal coupling apparatus
US4612519A (en) * 1984-01-14 1986-09-16 Communications Patents Limited Switch assembly and circuit
US4618838A (en) * 1984-02-27 1986-10-21 Sony Corporation Impedance adjusting element for a microstrip circuit
US4816789A (en) * 1986-05-19 1989-03-28 United Technologies Corporation Solderless, pushdown connectors for RF and DC

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6039999A (en) * 1993-08-11 2000-03-21 Hunt Wesson, Inc. Reduced fat nut butter product and process for making the same
WO1997015096A1 (fr) * 1995-10-18 1997-04-24 J.E. Thomas Specialties Limited Coupleur de sortie en sommet
US5675300A (en) * 1995-10-18 1997-10-07 J.E. Thomas Specialties Limited Top exit coupler
AU711308B2 (en) * 1995-10-18 1999-10-07 J.E. Thomas Specialties Limited Top exit coupler
EP0838704A3 (fr) * 1996-10-24 1999-05-12 Nortel Networks Corporation Structures pour transmissions de données et relatives à des configurations de fond de panier pour données
US5970193A (en) * 1996-10-24 1999-10-19 Nortel Networks Corporation Data communications structures relating to data shelf configurations
WO2019106497A1 (fr) * 2017-11-28 2019-06-06 Redox S.R.L. Système de communication modulaire multi-protocole
US10972137B2 (en) 2017-11-28 2021-04-06 Redox S.R.L. Multiprotocol modular communication system
WO2020021043A1 (fr) * 2018-07-27 2020-01-30 International Business Machines Corporation Dispositif cryogénique à multiples lignes de transmission ayant un atténuateur de micro-ondes intégré
US10790432B2 (en) 2018-07-27 2020-09-29 International Business Machines Corporation Cryogenic device with multiple transmission lines and microwave attenuators

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