MXPA97002450A - Derivation for community antenna television network - Google Patents

Abstract

A separator or shunt for use in a communication network, particularly a community antenna television network (TVAC), comprising: an input port for receiving an input signal; a past port for an output signal; a first portion of energy of the input signal and to make a second portion of energy towards the last port, and a removable energy distribution means that can receive said first portion of energy and has at least one energy output

Description

DERIVATION FOR COMMUNITY ANTENNA TELEVISION NETWORK DESCRIPTION OF THE INVENTION The present invention relates to a branch, or separator, for use in a communications network, particularly in a community antenna television (TVAC) network. Although several network architectures are used, these usually include a cable that runs from a transmitting or repeating station, etc., from which a signal must be derived to subscribers. This will generally occur in several positions along a cable line. As a result, the derivation must receive an input signal, separate part of it, and pass the rest over the next downstream separator. When no signal is separated to the subscribers, the device used is usually referred to as a separator, rather than a derivation. For convenience, the term "separator" will be used herein in a generic manner. It is usually necessary that the energy is supplied by the network operator to the subscribers, and said energy is conveniently sent along the same main cable that interconnects the separators. Therefore, the cable can carry a signal that combines energy, usually low frequency AC, and a high frequency signal, such as a radio frequency (RF) signal. In this case, the separator may have the additional function of separating the energy from the combined input signal. It has been found that the currently available separator designs are not easily adapted to particular field conditions or network requirements. As a result, several different designs must be produced depending on the number of subscribers; by separator, in the required attenuation and in the type of energy drop required, etc. In order to overcome these problems:; e has designed a separator that can be considered as a modular design. In this way, the present invention provides a separator comprising: an input port for receiving an input signal; a past port for an output signal; means for separating a first portion of the energy from the input signal and for passing a second portion of the energy towards the last port; and optionally a removable energy distribution module, which can receive said first portion of energy and which has at least one energy outlet. Also new and inventive is a separator comprising: an input port for receiving an input signal; a past port for an output signal; a port of signal drop; a physically removable circuit to separate a first portion of the input signal and pass it to the signal drop port and to pass a second portion of the input signal from the input port to the last port, and a switch that electrically interconnects the entry port and the last port under the physical removal of the circuit. These various aspects can be combined. The invention is further illustrated by the accompanying drawings, in which Fig. 1 is a perspective view of a separator, Figs. 2A , 2B, 2C and 2D are sections of a separator showing an internal switch, Figures 3A and 3B are partial perspective views of a separator showing a power drop port, Figures 4 and 5 are perspective views of a separator showing the addition of a power distribution node, Figure 6-8 show the sealing of cables to the ports of fall, Figures 9-11 stran the sealing of cables to main ports Figure 12 shows the sealing of isolated main ports, and Figures 13 and 14 show removable covers that carry the circuit system of the separator Figure 1 shows a separator 1 suitable for use in a network of TVAC The separator 1 comprises a housing 2 having several; ports on its external surface to connect to several input and output cables, having a system of internal electronic circuits and switches, etc., for dividing an input signal and / or for separating the energy of a high frequency component, and for providing the desired attenuation. As mentioned above, said separator is placed in a TVAC network at a point on a main cable line, where a signal is to be separated or derived, in order to be sent to the subscribers. In this way, the separator 1 has an input port (port 3 is used for a complete in-line configuration, and port 4 for a full stop configuration) to receive a cable that supplies a signal from a TVAC transmitter, etc., and a past port (port 5 or port 6 for in-line and buffer configuration, respectively) for connection to a cable that sends the signal (or part of it) further into the network, for example, towards another similar separator. The separator separates a portion of the input signal and supplies it to the signal drop ports 7, to which the drop cables are connected to the subscribers. The separator may have, for example, 2, 4, 6, 8 or more of said drop ports 7. The heater does not need to be provided with the portion for connecting the main cable in an in-line or stop configuration. Rather, it can only have 3 or 5, or only 4 or 6 ports (or one of each). Unused ports can be isolated as shown below.

The televisions or other equipment that will be supplied with a signal from the separator 1, will require, in general, an external power source, typically 60v AC. This energy is also conveniently obtained from the separator 1, which can receive it through a main cable connected to port 3 or 4. In this way, the main cable can carry a combined high-frequency energy and signal (generally the so-called RF or radio frequency) The subscriber can be provided with power through the drop cables that are to be connected to the drop ports 7, which will then probably carry a combined high frequency energy and signal. However, this can be inconvenient if a subscriber is not waiting for 60 volts, and so on, on his television drop cable, and it is preferred that the power be supplied through a dedicated power line. In this way, the separator 1 is provided with a dedicated port of energy drop 8. Therefore, some energy separated from the input line and sent to port 8, the rest of the energy being sent to the last port ( 5 or 6) to supply the next downstream separator. The separator, in general, will contain a low pass filter to remove the high frequency signal from the drop power supply. The separator can be provided with means such as slots 9, other depressions, or protuberances, over its ports, etc., to secure environmental seals either to seal the entrance cables or to locate the insulation shutters. Figure 2A is a section through a separator similar to that shown in Figure 1 (taken in a plane substantially parallel to the page and seen from the back) The Figure 2B is a section taken along the arrows in Figure 2A, and Figures 2C and 2D are sections perpendicular to that direction. In Figures 2A-3D, housing 2, input ports 3 and 4, past ports 4 and 6 and the drop ports The ports are designed for connection to coaxial cables (although ports for other cables can be provided), and it is preferred that these be receptacles to receive the cable connectors attached to the cable ends , or to directly receive cables prepared with stepped ends. Contacts 10 can be seen for an internal conductor of a coaxial cable, and contacts 11 for an external conductor. A switch 12 is also shown comprising mobile contacts 12A and 12B which, when closed , electrically connect the input port (3, 4) with the last port (5, 6) As a result, when the switch is closed, any input signal is directed directly from the port Inlet to the last port without a portion thereof being spaced to the falling ports. However, this switch 12 may be caused to open when the appropriate separation circuit system is put in place. Then, the direct path between the input ports and the past ports of breaks, and the separation circuit system then interconnects those ports and directs some of the signal towards the drop ports 7. This circuit system is not present in the Figures 2A-2D, and as a result, switch 12 closes. The circuit system may be provided mounted on a removable cover, which, when in place, may be in a plane just above that of Figure 2A, and as it is put in place, it may cause the contacts 12A and 12B separate. A lower metal surface of the housing 2, for example, the wall on the right hand side shown in Figure 2B, can constitute a plane connected to ground. It is preferred that any moving part of the switch moves substantially parallel to a ground plane, so as not to alter the high frequency characteristics of the separator as the contacts move. Switch 12 is desirable in order for service to be provided downstream of the separator when the separator circuit system is absent.; it may be desirable to remove said circuit system in order to place it with a different circuit system (for example, to provide more or fewer drops, or to repair or improve, etc.). It is preferred that the removal of the circuit system does not produce any momentary break in the service, and therefore that the physical removal of the circuit results in: 1. the electrical interconnection of the input port and the last port (through the switch); and then 2. the electrical disconnection of the circuit from the input ports and from the past ports. Subsequent replacement of the circuit system should similarly make a contact between the input and last ports (via the circuit system) before breaking the direct contact by opening the switch 12. In order to prevent the circuit system from being left partially in place (that is, when the connection is made between the input port and the last port, both through the switch and through the circuit) it is preferred that the circuit pass through a position in which the interconnection (1) is made, and in which the disconnection (2) has not been made, said position being unstable. Preferably, a single movement (e.g., movement in a straight line away from the housing) causes interconnection (1) and disconnection (2). Also, it is preferred that the physical removal by itself causes the interconnection / disconnection, rather, for example, before the removal of a coupling or the non-completion of a closure. The switch 12 is preferably mechanical, but may be an electronic switch, and is preferably activated mechanically through the direct mechanical or physical movement of the circuit or a cover, etc., to which it is attached (including some protrusion or other projection of the cover). Figures 2A, 2C and 2D also show means 13, such as a coil for transferring energy from the inlet port 3 4 to the last port 5 or 6. Preferably, the means 13 act as a low pass filter or another way they transfer the energy substantially alone, that is, without any significant high-frequency signal, RF or other signal, that enters the input port. It will be desirable if the means 13 act as a separation of energy, or derivation, for the provision of energy to the subscribers. For example, the energy can be taken, at a midpoint of the coil to an energy drop port, such as port 8 of Figure 1. Despite the filtration inside the body of the separator through the means 13 , some additional filtration may be desirable. Said additional filtration may be provided within an addition energy distribution module, which will be described later. Figures 3A and 3B show the removal of a cover from the power drop port 8 The cover can be removed simply by pulling or unscrewing, as shown in Figure 3A, or especially in the case of an integral or joined cover by cutting , as shown in Figure 3B. Fig. 4 shows the separator with the cover removed from the energy drop port 8 located on an external surface of a spacer housing 2. In port 8, a gel or other internal sealing material 15 can be seen. A power distribution module 16 is next to be connected to the separator, the electrical connection being made between, for example, the internal and external coaxial contacts, 17 or 18, on the module 16 and the corresponding contacts in the drop port 8. The module 16 can be physically secured to the housing by means of snap fastening or interference fastening hooks, 19A, or through a bolt in a hole 19B or through any suitable means. Figure 5 shows the module 16 installed on the housing. It is preferred that any removable module 16 is not primarily responsible for the energy separation of an input energy plus the high frequency signal. It is preferred that means be set to initially separate the energy, inside the separator housing. Any of the various functions can be provided by the module. For example, the module can distribute the energy obtained from a single port 8 on the separator housing to at least two energy outputs 20 and / or to a different type of output from port 8, for example, to an output suitable for the connection to a twisted pair fall. Said power outputs may comprise isolation-displacement connectors, or other means to ensure a conductor drop. Preferably, each outlet has means for connecting two conductors, such as those of a twisted pair wire 21 Each outlet may be provided with a gel or other means for environmental sealing The number of outlets will generally be equal to the number of signal ports of fall, since each suscpptor will usually require its own separate, dedicated, own power supply An additional or alternative function provided by module 16 is filtration The same separator can not be provided with a filter to remove high frequency signals from the fall of energy, or any filtration may be inadequate. Module 16 may therefore provide low-pass filtration or other appropriate filtration. Additional or alternatively electrical protection may be provided. Overcurrent or overvoltage protection devices may be used within the module, to prevent the current or voltage induced in or applied to any drop that damages the circuit system of the separator or the head end transmission or reception equipment, or that damages another equipment of the suscpptore:; Such devices can also protect the suscppior equipment against currents or voltages in the main lines between the separators The devices are preferably erasable and preferably automatically reconnected Examples of suitable overcurrent devices include those based on conducting polymelia, such as those sold by Raychem under the trade name of Polyswitch Figures 6-8 show various ways to seal cables 22 to drop ports 7. Figure 6 shows wires 22 terminating in connectors 23, which are screwed or otherwise fixed in ports 7. The connectors 23, a portion of the cables 22 adjacent the end of the connectors, and the ports 7 are environmentally sealed by enclosing them in sleeves 24. The sleeves 24 preferably comprise a flexible plastic material, optionally containing a gel or other sealing material, and which optionally has a coupling 26 that fits to a latch, such as the slot 9, over the ports 7. The sleeves 24 can have a bellows or corrugated region to facilitate flexing and / or extension capacity and compressibility. A sleeve is shown prior to insertion on a port, with a branch 25 that can close a cable passage therein allowing the sleeve to be used to seal an empty port. A section through a sleeve 24 is also shown to illustrate its internal structure. In Figure 7, an alternative design of the sealing sleeve is shown. The sleeve 27 is of a so-called wrapping design and, therefore, can be installed around a cable 22 when it is connected to a port 7. Thus, a replacement seal can be made without interrupting the service to the subscriber. The sealing sleeve 27 comprises two parts hinged together at 28, and having hooks to lock the ports in the closed position. A tool 30 can be provided to connect the connector 23 to the port, parlicularly if the connector is short and does not leave the port as shown in the upper right part of the four ports. The wrapping sleeves 27 can be instantaneous and locked onto the ports through means such as 26 and 9, in a way that does not allow them to reopen without damage. This can prevent casual tapering with the separator to drive the signal. The sleeves of Figures 6 and 7, particularly those of Figure 6 can be used in a large scale of cable sizes and ports. Figures 8A, 8B and 8C show how a port can be sealed without an outer sleeve separate from the type shown in Figures 6 and 7. Port 7 (particularly a contact 7A thereof) has access through a hole 32 (here defined by a straight cylindrical wall surrounding the screw contact 7A) on an external surface of the separator. The port 7A is surrounded by a sleeve 33. When a connector 23 is screwed or otherwise attached to the hub 7A, the sleeve 33 is forced to contact the edges of the hole, thereby forming a seal between the connector and external surface . Figures 9 and 10 show the installation of a sealing and / or security wrapping sleeve 27 for the main cables , where they enter the port of entry and the last port. The sleeve may contain a gel or other sealing material. In general, it may be similar to the one shown in figures 7, but larger.

Figure 11 shows a bellows type sleeve 24, similar to that shown in Figure 6, being used on a main cable 3 £. Figure 12 shows a seal branch 36, which contains a gel or other sealing material, which will be placed on port 4. A branch 36 is also shown in its place. The shunt 36, the sleeve 24 and the sleeve 27, and other devices for environmental sealing, may be provided with means for maintaining under pressure any gel or other sealing material, which will contain or otherwise be used therewith. It is desired that said sealing material be held under compression so that it remains in contact with the surfaces to be sealed. The compression can be maintained by the elasticity of the branches and sleeves and / or the spacer housing. Alternatively or additionally, other elastic hooks may be employed. The sealing compound preferably comprises a gel.

Preferably, it comprises an oily extended polymeric material. It is preferred that it has a cone penetration value of 800-400, especially 200-200 (10"1mm) (ASTM D217-68) and a final elongation of at least 100% (ASTM D638-80), especially by at least 200% Other preferred properties include a final tensile strength (ASTM D412) greater than 1 MPa, a dynamic storage modulus less than 50 KPa, and a substantially zero depression at 100 ° C, preferably up to 120 ° C An advantage of a material such as a gel is that it can be self-sealing.As a result, an environmental seal is automatically made by removing a cable, connector, module, or circuit board, etc. Figures 13 and 14 show separators 1 having a housing 12 and a cover 37 therefor In Figure 13, the Meya cover a physically removable circuit, components 38 that can be seen, to separate a first portion of an input signal entering port 3 and which is passed to signal drop ports 7, and to pass a second portion of the input signal to a past port (dark part in Figures 13 or 14). It can be seen that removing the cover 37 opens the housing and causes the circuit to be removed. It is preferred that the removal of the separator circuit leaves the means to derive the undistributed energy in the separator housing. In Figure 13, the drop ports 7 are mounted on an opposite surface 39 of the spacer to the cover 37, so that the removal and replacement of the cover breaks and makes electrical connection between the ports and the electrical circuit. Some contacts (not shown) will be provided within the separator, at each drop port and main port and at corresponding locations on the adjacent electrical circuit. In Figure 14, the drop ports 7 are mounted on the removable cover 39. Here, the connections between the drop ports and the electrical circuit may be permanent, but the design has the disadvantage that the entrance to the interior of the separator, or the interchange of the cover plus the circuit system, requires that the ports of fall be transformed.

Claims (7)

1 - . 1 - A separator comprising: an input port for receiving an input signal; a past port for an output signal; means for separating a first portion of the energy from the input signal and for passing a second portion of the energy towards the last port; and optionally a removable energy distribution module, which can receive said first portion of energy and which has at least one energy outlet. 2. A separator according to claim 1, wherein the means for separating the energy separates the energy substantially only from a combined energy and a high frequency signal. 3 - A separator according to claim 1 or 2, wherein the module includes a low pass filter. 4 - A separator according to any of claims 1, 2 and 3, wherein the module includes protection against overcurrent and / or overvoltage. 5 - A separator according to any of the preceding claims, wherein the module has at least two power outputs. 6. A separator according to any of the preceding claims, wherein the or each of the energy outputs comprises an insulation displacement connector 7 - A separator according to any of the preceding claims, wherein the or each one of the energy outlets is environmentally sealed 8 - A separator according to claim 7, wherein the environmental seal is provided through means comprising a gel 9 - A separator with any of the preceding claims, wherein the module it is removable without removal of the means for separating the energy 10 - A separator according to claim 9, having a power drop port with which the module may coincide 11 - A separator according to claim 10, in where the power drop port is on an external surface of the separator 1

2 - A separator according to any of the preceding claims is, wherein the module is mounted on the outer surface of the separator 1

3 - A separator according to any of the preceding claims, having a port to which a cable copector can be attached, the port having access through a hole on an outer surface of the separator and being surrounded by a sleeve, so that when the connector is attached to the port, the sleeve is forced to contact one edge of the hole thus forming a seal between the connector and the external surface 1

4 - A separator according to any one of the preceding claims, having a dedicated power drop port that receives said first portion of energy and with which the module can match a separator according to any of the preceding claims, which has means for separating a first portion of high frequency signal from an input signal and for passing a second portion of high frequency signal recuence of the input signal to the last port 16 - A separator according to claim 15, having a dedicated signal drop port for receiving said first high frequency signal portion 17 - A separator comprising an input port for receiving a power and a high frequency input signal, combined, a past port for a power and a high output frequency signal, combined, a power drop port, and means for separating a first substantially single power portion of the input signal and to pass it to the power drop port, and to pass a second portion of energy towards the last port 18. - A separator according to any of the preceding claims, further comprising: a signal drop port; and a circuit for separating a first high frequency portion of the input signal, and passing it to the signal drop port and for passing a second high frequency portion of the input signal from the input port to the last port. 19. A separator according to claim 18, further comprising: med io s to directly interconnect the port of entry and port pasado