A Passive Adapter for Home Networks
Field of the Invention
The present invention relates to the field of local and home networks. More particularly, the invention relates to a secondary use of existing home or building cables to form an extended local network.
Background of the Invention
As the number of electronic devices with built in communication capability in houses increases, there is a demand for a way to permit those devices to communicate between them and with external networks. Many houses are equipped with cables (or wires) of various types as a part of the house infrastructure. Typically, said various cables may include electricity cables, telephone cables, TV cables, intercom cables, etc. Hereinafter, all said cables that have been primarily and originally dedicated for use by the various equipments within the house will be referred to herein as "infrastructure cables".
Several communication standards have been developed to allow a secondary use of said infrastructure cables, specifically for the purpose of home or local networking (hereinafter, the term "home network" will be used to cover both of said type of networks). However, the evolving standards, and the increasing need for a higher data rate do not appear to enable efficient secondary communication over all the various types of the infrastructure cables. As a result, the existing standards and devices require in many cases the addition of dedicated wiring to the existing ones, or to use wireless communication. Wireless communication, however, does not always provide the ultimate solution, as it also requires connection to the main electricity supply, does not always cover all the locations within the house, and does not always meet the required data rate. Therefore, in many cases there is a need for the use of wired communication, or for a combination of wired and wireless communication.
Home network technologies using coax cables are known. The Multimedia over Coax Alliance (MoCA™, see mocalliance.org), provides examples of a suitable specification and products (MoCA 1.0, Netgear MCABlOOlMoCA Coax-Ethernet Adapter Kit (Black), and ACTIO NTEC Model #: HCB1000 HPNA over coax) for networking of digital video and entertainment by means of a secondary use of an existing coaxial cable. Home networking over coax taps into the vast amounts of unused bandwidth available on the in-home coax. More than 70% of the homes in the United States have coax cables already installed within the home infrastructure. Home networking technology allows homeowners a secondary use of cables within the house infrastructure for networking, and to deliver other various types of entertainment data with high QoS (Quality of Service) and at high speed (270 Mbps).
However, unlike electrical outlets that typically exist in all the rooms of the house, most houses are equipped with coax cables and outlets for said cables only at specific locations of the house, such as family rooms, media rooms, or main bedrooms. Therefore, the existing coax cables can provide only a limited solution to the secondary need for a high data rate communication between various devices (such as computers, TVs, game devices, etc.) within the house.
With the growth of the market and the need to distribute data, it becomes apparent that the limited coverage of wireless networks can not fully answer the need for distributing data at rates above 100 Mbps, such as required by various applications including for example video over IP, or high definition video. Even when providing a powerful wireless access point in one room of the house, other rooms may still suffer a bad wireless coverage due to concrete walls and other interferences. Moreover, as the data rate increases, the area covered by the wireless network decreases, for example, the most up-to-date protocol of the wireless network, namely 802.11η, specifies a data rate of more than 100Mbps at an open space up to 20 meters.
HomePlug technology utilizes the electrical wires of the house for a secondary use, typically for communicating broadband Internet, HD video, digital music or smart energy applications between rooms of the house. Installing a data network over the electrical wires using HomePlug technology is done by plugging in communication modems and connecting them to an Internet Service Provider (ISP). A typical installation starts with the connection one communication modem to the ISP by an Ethernet cable, and then plugging the communication modems into the nearest power outlet. The addition of a new access point to the network simply requires the plugging in of a communication modem to an outlet where the access is required. Once the communication modem installed Internet devices may be connected to it through an Ethernet cable. The power-line modem can also be plugged into a hub or switch when multiple devices (computers, printers, IP phones, etc.) need to be connected in a single room.
Various solutions have been developed to overcome the limited coverage problem by home wireless communication. Corinex, (HD200 homeNET coax or AV256 CableLAN adapter, http://www.corinex.com/in-building- solution-2.html) uses the existing electrical lines or coaxial cables as a network backbone. Corinex does not support the secondary use of the telephone twisted pairs wires for the purpose of home networking. In addition, when both coaxial and power lines are available, the user has to select one of said types of lines, by manually switching a controller.
Another attempt to provide a reliable and high performance a home network at unlimited coverage by a secondary use of existing infrastructure cables is offered by Eicon (Elconnect coax, http://www.elcon- system.de/index.php ?id=l&L=2). Eicon requires the user to determine the selected network (Coaxial or power line) by utilizing a manual switch. Said switch is also employed for preventing the noise and mutual interferences between the various channels of the network. Devolo (D LAN 200, D LAN 500, www.devolo.com) also provides IP over power line and coax. However, their solution works only on coax or on a power line, and does not support phone lines.
As previously mentioned, high speed home network systems which utilize the various infrastructure cables in the house for networking, exist in the art. Such prior art systems comprise an Ethernet Communicating device which is connected on one hand to any type of home device (such as computer, TV, TV Cable Modem, IPTV, IP Telephony , IP camera, etc.) or an Ethernet provider modem and on the other hand to one or more of plug sockets within the house. When the house is built in such a way that the coax, phone and power wires are connected to the same central wiring point and a star topology wires network reaches every room, the prior art systems allow to connect the coax and power wires as one network by connecting them through a multi-wire Ethernet modem.
However, in most cases the house wiring topology is not a star topology. When the wiring topology is a daisy chain, the telephone, coax, and power wires reach different places in the house. Thus, typically there is no single place where all the three types of wires are close one to all the others, and therefore it is impossible, or rather very expensive to form a home network which utilizes the various cables in the house.
Even though prior art systems can establish a home network over one or two of different type channels (i.e., electrical, and/or coax), they cannot also combine with the telephone cables to establish one united home network. Furthermore, all those prior art devices that can bridge different types of infrastructure cables to establish a united home network are active devices, that require an Ethernet modem, electronic circuitry, and power supply. Therefore, those devices are expensive, require settings and maintenance, and continuous supply of electricity.
Therefore, a need exists in the art for a passive device for bridging between two types of infrastructure networks, thereby to form a united home network, while addressing the drawbacks of the prior art as noted above.
It is therefore an object of the present invention to provide a plug-and-play device adapted to transfer IP information between different existing wires structures.
It is another object of the present invention to provide a system which is adapted to connect different types of wires structures.
It is an additional object of the present invention to provide a passive system which consumes no power.
It is another object of the present invention to provide a durable system having a long life time. It is another object of the present invention to provide a highly cost- effective system.
Other objects and advantages of the invention will become apparent as the description proceeds.
Summary of the Invention
The invention relates to a passive adapter for bridging two or more types of infrastructure networks, comprising: (a) plurality of ports each of said ports being connected respectively to one of said infrastructure networks;
(b) plurality of filters, each of said filters being associated to one of said ports for preventing interferences between plurality of said networks; and
(c) one or more transformers, each providing insulation between any two of said types of infrastructure networks, and it further provides impedance matching.
Preferably, the two or more types of infrastructure networks are selected from the group comprising power-line, coaxial, and phone-line.
Preferably, the passive adapter is passive in terms of not consuming power from the main electricity network for its operation.
Preferably, the passive adapter is bridges two or more types of infrastructure networks by plugging one port of the adapter to one socket of each type of infrastructure network.
Preferably, the passive adapter is further bridges between two separate power line networks, each belonging to another electrical phase.
Preferably, the passive adapter band width is in the range of 0-65 MHz. Brief Description of the Drawings
In the drawings:
Fig. 1 is one exemplary embodiment of a network formed using a passive adapter;
Fig. 2 schematically illustrates a block diagram of the passive adapter according to one embodiment; and
Fig. 3 illustrates a circuit diagram of one exemplary embodiment of the passive adapter.
Detailed Description of the Invention
The present invention provides means for connecting the power wires network, the coax wires network, and the phone wires network to establish one home network. A passive network adapter is utilized for connecting the different wires networks that exist in the house. Utilizing one or more passive adapters allows bridging two or more wires networks in the house. The expanding of the network to operate over multiple types of cables is relatively easy, and requires only connecting the passive network adapter between two different sockets positioned close one another. For the multi channel embodiment, the passive adapter connects between several sockets. Each passive network adapter is typically a plug- and-play device which is capable of transferring automatically the data arrives from a network over one type of infrastructure cables to another network operating over another type of infrastructure cables. The data transfer between the bridged networks is bi-directional, namely, the data can transfer data from one channel (i.e., operating over one type of infrastructure cable) to another channel and vice versa. In one embodiment, the bandwidth is in the range of 0-30 MHz. In another embodiment the band width is in the range of 0-65 MHz. Fig. 1 is one exemplary embodiment of a network formed over infrastructure cables, using the passive adapter of the present invention. In this embodiment the network coverage is extended using only the infrastructure cables of the house 102. For example, in room A power line 101 is one of the infrastructure cables being used for extending the network coverage. Internet Service Provider (ISP) 103 communicates with the house in a conventional manner using ISP modem 104 which is located at room A of the house. A power line Ethernet modem 105 is connected at room A to the ISP modem 104 using a network cable (CAT5). The power line Ethernet modem 105 is connected from its other side to the power line outlet 106. Other Ethernet modems are connected similarly to other Ethernet home devices. For example, Coax Ethernet modem 131 is connected at room C to an IPTV (Internet Protocol TV) device 132 through its Set-top box 137. A phone Ethernet modem 120 is connected at room B to a PC 121. Once a power line Ethernet modem 105 is connected to the ISP modem 104, it may be connected to a power line plug socket 106 available at the respective location.
In this example, the power line Ethernet modem 105 is connected at room A to the power line sockets 106, and therefore it is capable of communicating data to any power line socket which is available in the house, assuming a same electricity phase wiring. However, the power line wires in rooms A and B belong to two different electrical phases, and this is also the case for the power line wires in rooms A and C. Therefore, Ethernet modem 105 which is connected to the power line at room A cannot support delivery of Ethernet packets to any of room B or C in view of their connection to different electrical phases. The passive adapters of the present invention provide a cost-effective solution, by enabling Ethernet communication from room A to any of rooms B or C, and enable expansion of the network coverage to the entire house. In this embodiment, a network which covers the entire house 102 is formed by utilizing two passive adapters 110 and 115. A passive adapter is a plug-and-play device adapted to transfer data between different types of infrastructure wires, namely, between power line, phone, and coax lines in this example. Each passive adapter connects between two different types of infrastructure wires by bridging their sockets. In this example, passive adapter 110 connects power-line socket 111 to coax socket 112, passive adapter 115 connects power-line socket 113 to phone socket 114. Thus, data can be communicated from room A to rooms C and B through the coax cable 117 and the phone cable 116 respectively.
The passive adapter consumes no power, therefore offers a durable device having a long life time. The simplicity of the passive adapter makes it highly cost-effective. The passive adapter significantly reduces the costs of forming a house network. By bridging power line socket 113 and phone socket 114, data can be transferred to the phone socket 122 in room B. The passive adapter 115 allows transfer of data to room B over the phone infrastructure 118 without using an additional modem. Utilizing the passive adapter allows transmission of data to a long distance over coax or phone line, rather than over a power line only. Therefore, the passive adapter improves the quality of the transmitted signal, and reduces the noise in the line.
In another embodiment, a passive adapter (not shown) can be used to bridge phone socket 122, and power line socket 123, establishing data connection between the power line wiring network 116 of room A, to the power line wiring network of room B 124, while said two rooms use two different phases. Moreover, when using passive adapters to bridge between the coax network and power line network, and between the phone network and the power network, all three different types of networks are connected to form one network. Still another option to connect the entire house to form one network is to use passive adapter 134 in room C. Passive adapter 134 bridges phone socket 135 and coax socket 136, According to this embodiment, data can be transferred from room A to room B, through room C even if there is no power line wire or power socket available.
Fig. 2 schematically illustrates a block diagram of the passive adapter 201 according to an embodiment of the invention. In this embodiment the passive adapter has three ports 202, 205, 210 adapted to connect to the three house infrastructure lines, power lines, coax lines, and telephone lines. Port 203 is adapted to connect to the power line of the house. Port 210 of the passive adapter is adapted to connect the phone line. Port 205 is adapted to connect the coax line. The passive adapter is adapted to bridge all types of house infrastructure lines, e.g., power line to coax, power line to telephone, coax line to telephone, etc. The passive adapter also supports splitting data from one network to the two other networks, e.g., from power line network to the coax line and phone line networks. The following discussion describes the manner of connecting one type of network to another type of network. Likewise, splitters, combiners, and set of filters can also be used to include within a same casing multi-channels adapters. Bridging two or more types of infrastructure networks can be done by simply plugging one port of the adapter to one socket of each type of infrastructure network.
Once a signal is received from the power line network port 203, it is filtered by filter 206, and then conveyed to a transformer 207. Filter 206 prevents collision and interference between the internal of the passive adapter and the power line network. The transformer 207 is responsible for insulation and impedance matching with the respective channels wires for maximizing the power transfer and minimizing reflections from one type of network to another. Typically, the passive adapter utilizes one transformer between network ports of two types. In this embodiment, filter 206 also eliminates the high voltage component from the signals arriving from the power line network. After the signal is transformed by transformer 207, it is filtered again using filter 208. In this embodiment, filter 208 prevents collision and interference from the internal of the passive adapter to the coax network at 205. In another embodiment the passive adapter bridges more then two types of networks, therefore, more then one transformers are used in one adapter. The signals conversion is bi-directional, namely, the adapter can convert from the power lines to the coax and telephone lines or in the opposite direction, i.e., from the coax and telephone lines to the power lines.
Fig. 3 is a circuit diagram of one exemplary embodiment of the passive adapter 301. In this embodiment the capacitance, resistance, and inductance values of the capacitors, resistors and coils respectively have been selected to allow all channels (power-line, phone, and coax) to passively transfer data between them. Power-line connector 302 is used for connecting the passive adapter 301 to the power line network. The signal from the power line network is transferred through a transient absorber 303 to a High Pass Filter (HPF) 304 for reducing the signal voltage level, and preventing interferences between the power line and the coax or phone lines. The filtered signal is then conveyed to transformer 305, and from the transformer to a coax connector 306, and to a phone line connector 307.
The passive adapter of the present invention enables a reliable broadband communication between different types of infrastructure cables in a house. The data is transferred over an unused frequency spectrum, which prevents interruptions to applications in a LAN that are bandwidth consuming and sensitive to delays. One may easily watch standard television broadcast through an IPTV and access the internet at the same time while using a united network which is combined from two or more types of infrastructure cables, while said different cables are bridged using the passive adapter of the present invention. In one embodiment the data frequency is in the range of 5-30 MHz. In another embodiment it may be extended to 0-65 MHz.
While some embodiments of the invention have been described by way of illustration, it will be apparent that the invention can be carried out with many modifications, variations and adaptations, and with the use of numerous equivalents or alternative solutions that are within the scope of persons skilled in the art, without departing from the spirit of the invention or exceeding the scope of the claims.