Patent Application
20160294500
Telecommunication systems employ a variety of cellular systems and devices to wirelessly transmit/receive voice and data signals over large geographic, or small confined, areas. Outdoor macro telecommunications sites typically employ, inter alia, a plurality of telecommunications antennas, e.g., sector antennas, mounted atop elevated towers/scaffolding/buildings, for the purpose of transmitting/receiving RF signals, i.e., providing cellular coverage, over a large geographic area. Such land-based antennas may communicate with orbital telecommunications satellites, localized telecommunications systems or Distributed Antenna Systems (DAS).
Distributed Antenna Systems (DAS) augment radio frequency (RF) communications, i.e., cellular coverage, provided by global satellite or land-based antenna systems. More specifically, a DAS provides coverage in spaces, buildings, tunnels, etc., which would otherwise block, attenuate, absorb or interfere with the RF signals/energy transmitted/received by the global satellite systems. Such spaces include high-rise buildings, hotels, stadiums, universities, casinos, etc., where RF coverage is essential for uninterrupted and reliable telecom service. The objective of a Distributed Antenna System (DAS) is to provide a uniform RF coverage within a confined space to optimally or selectively distribute RF energy within the space.
Land-based antennas or Macro Antenna Systems (MAS) typically include: (i) a Base Transceiver Station (BTS) providing RF signals from local service providers, e.g., Verizon, Comcast, AT&T etc., through a Base-Band Unit (BBU), (ii) a Remote Radio Unit (RRU) communicating RF data with the BBU and operative to augment, amplify, attenuate, and transmit RF signals received from the BBU, (iii) a plurality of telecommunication antennas each connecting to an RRU, and a (iv) a tower/scaffolding/elevating structure for mounting the RRU and telecommunication antennas. The BBU is disposed in the equipment room/Base Transceiver Station (BTS) and connected to the RRU via a combination of optical fiber and copper wire.
Similarly, a Distributed Antenna Systems, or DAS typically includes, at one end: (i) a plurality of Base Transfer/Transceiver Stations (BTS) providing the RF signals of each service provider, e.g., Verizon, Comcast, AT&T etc., (ii) a DAS head-end for receiving, handling, and manipulating the various RF signals of the Base Transfer/Transceiver Stations, (iii) a plurality of Remote Units (RUs) amplifying/attenuating signals received from the DAS head-end, and (iv) a telecommunications antenna connecting to each of the remote units at the other end of the DAS. Similar to a MAS, the DAS head-end connects to each of the RUs by a plurality of conductive and fiber optic cables.
A DAS may comprise a variety of system types including passive, active and hybrid systems. Passive systems employ conventional coaxial cables to distribute telecommunication signals within an internal space, active systems typically employ optic fiber cable to distribute RF signals, while hybrid systems employ a combination of the passive and active systems. A passive system is less complex to implement inasmuch as coaxial cable is inherently capable of handling multiple carrier frequencies employed by the RF service providers. However, the strength of the radio signal rapidly diminishes the more distal the cable is from the signal source. Consequently, passive systems are not well-suited for large facilities having long/complicated cable runs, and cannot provide end-to-end cable monitoring. Active DAS, on the other hand, delivers strong and consistent signals at every node irrespective the distance from the signal source. Furthermore, active DAS is capable of monitoring nearly all system components, e.g. the remote units and antennas, using conventional Simple Network Management Protocol (SNMP). Additionally, an perhaps most importantly, fiber optic cable, used in active DAS, can be run over large distances without losing signal strength. Moreover, fiber optic cable can be less expensive to install inasmuch as the cabling is lighter and easier to deploy across ceilings and in tight spaces.
One difficulty or challenge common to both MAS and DAS telecommunication systems relates to providing economical and safe power to each system. More particularly, one challenge relates to minimizing the cost of providing copper cable over large distances. Generally, copper wire having a diameter corresponding to a gauge of between about two (2) to four (4) will be required to transmit high voltage across a relatively short distance, e.g., a run of above fifty to one-hundred feet (50 ft-100 ft.), which corresponds approximately to the height of a conventional cell-tower/elevated structure. Inasmuch as the diameter of the copper wire cable is approximately two to two and one-half inches (2″-2½″), such copper wire cable cannot be easily wound around a spool for distribution/storage/transport and must be specially-ordered wherever such cable is needed for fabrication, maintenance or repair of a cell-tower. Additionally, it will be appreciated that the lead-time for fabrication can be several weeks to several months.
Additionally, the copper wire cable used to carry such voltages must remain “Class 2” compliant for the purpose of fire and electric shock safety. To be Class 2 compliant, the telecommunications system must be powered by an analog circuit having a potential less than (<) about 60 volts with a total power less than (<) about 1000 watts. Alternatively, the wire cable must be protected within a conduit and installed by a licensed electrician. As a consequence, the cost to install a DAS in a typical stadium or high-rise building can be prohibitive, e.g., in excess of $670,000, when considering the cost of employing a licensed electrician, at some $67.00/ft to install. With respect to a MAS, the cell tower and cable may be inherently protected within a fenced or secure perimeter. However, this protection does not reduce the cost of the heavy gauge copper wire used to transmit power and data from the base transfer station to a remote radio unit mounted atop a typical cell tower.
The foregoing background describes some, but not necessarily all, of the problems, disadvantages and challenges related to the reuse of cable connectors.
Additional features and advantages of the present disclosure are described in, and will be apparent from, the following Brief Description of the Drawings and Detailed Description.
A power-data distribution system is provided including a packet energy transfer (PET) system, a converter, a conductive cable and a fiber optic cable. The PET system transmits discrete packets of digital energy and produces a continuous stream of analog power. The converter reduces the analog power from the first to a second potential, wherein the second potential is lower than a threshold potential. A conductive cable transmits the discrete packets of energy from a power source to a load while a fiber optic cable exchanges data between a data source and the target device.
A telecommunication system is also described including: (i) a master unit operative to exchange data from at least one base transceiver station, (ii) at least one telecommunication antenna operative to exchange the data with the wireless communication devices, (iii) a remote unit connecting the master unit to the telecommunications antenna and including a ground-hardened outer casing, and, (iv) a Packet Energy Transfer (PET) power distribution system operative to transfer packets of electrical energy from a PET transmitter to a micro-receiver, the micro-receiver powering the remote unit and disposed internally of the ground-hardened outer casing thereof.
Overview
The following describes various components of a Wireless Telecommunication System. In one embodiment, a local telecommunication system is described in the context of a Distributed Antenna System or DAS which includes a plurality of small canister antennas distributed within a defined space. In other embodiments, a regional or global telecommunication system is described in the context of a Macro Antenna System or MAS which includes a tower/elevated structure to mount an antenna system which sends and receives data by an orbiting satellite and/or land-based antenna systems.
In one or more subsequent sections, each of the DAS and MAS telecommunication systems are powered by an integrated Packet Energy Transfer (PET) System. In one embodiment, a wireless fidelity (WIFI) system is integrated with the PET-powered telecommunication system for communicating with Wireless Application Protocol/Access Point (WAP) enabled devices.
In each embodiment, the DAS/MAS telecommunication systems include a Network Switching Subsystem (“NSS”) having a circuit-switched core for making phone connections. The NSS also includes a general packet radio service architecture which enables mobile networks, such as 2G, 3G and 4G mobile networks, to transmit Internet Protocol (“IP”) packets to external networks such as the Internet.
A service provider or carrier operates a plurality of centralized mobile telephone switching offices (“MTSOs”) each controlling a base transceiver station associated with a MAS within a select/cellular region surrounding the MTSO. One or more DAS may operate within, and transfer telecommunications signals between, telecommunication system subscribers and the head-end of a service provider. The DAS may also distribute WIFI for connection to a Wireless Access Port or WAP of an Internet connection.
In
In
Packet Energy Transfer (PET)
While the foregoing provided a brief overview of a MAS and DAS telecommunication systems 2, 10, the following discussion describes a novel power source therefor. More specifically, each of the MAS/DAS telecommunication systems 2, 10 includes a power source which employs Digital Energy or Packet Energy Transfer (PET) technology. Before discussing the PET-Powered telecommunication systems 2, 10, it will be useful to briefly describe this type of power source/supply.
Digital Energy or Packet Energy Transfer (PET) technology (hereinafter referred to as Packet Energy or “PET”) is a power distribution system which separates electrical power into a series of discrete time domains referred to as digital energy packets. Each packet includes a first time domain for energy transfer, and a second time domain for digital/analog signature verification. Using this approach, much higher levels of power can be safely transmitted from a power source to a load, i.e., downstream equipment. For example, three-hundred and forty-five volts (DC 345 V) can be safely delivered using PET technology in contrast to just fifty-six volts (DC 56 V) when delivering analog power over a conventional Category 5 or Category 6 cable. More specifically, PET technology is capable of distinguishing between an individual/technician inadvertently making contact with a power conductor and the current drawn by powered equipment.
Specifically, a sensing circuit is provided to rapidly determine when a hazardous/potentially dangerous condition is present. The circuit shut downs down before another packet of high voltage digital energy is transferred. The same circuit safely, and continuously, operates when detecting that the potential draw is steady, such as when electrically powered equipment draws current from the power source. This sensing circuit has proven to be sufficiently reliable that regulatory authorities now consider digital energy/PET technology to be on a par with an analog Ground Fault Interrupt (GFI) circuit—deemed, by some, to be the gold-standard in safety in analog circuitry.
A Packet Energy Transfer (PET) system suitable for powering the telecommunications systems described herein is more fully described in Eaves U.S. Pat. No. 8,068,937 entitled “Power Distribution System with Fault Protection Using Energy Packet Confirmation,” filed Feb. 4, 2009, and Eaves U.S. Pat. No. 8,781,637 entitled “Safe Exposed Conductor Power Distribution System,” filed Dec. 7, 2012 which are both incorporated herein by reference in their entirety.
PET-Powered Telecommunication System (DAS Embodiment)
In
In the described embodiment, the DAS telecommunication system 100 provides an even distribution or blanket of RF energy within a prescribed/selected/confined space. As discussed in a preceding paragraph, such spaces include high-rise buildings, hotels, stadiums, universities, casinos etc., where RF energy from external satellite or Macro Antenna Systems may be blocked from entering the space due to attenuating/absorptive structure employed in its construction. Accordingly, the DAS telecommunication system 100 reduces interference, isolation and reflection losses in the signals exchanged between an internet/network-enabled device and a service provider.
More specifically, the master unit 102 processes the telecommunication signals transmitted/received by the BTS Units 104, i.e., the signals from the various service providers, such that all of the signals and frequencies of the various carriers may be transmitted/received by one of the target devices, i.e., a target device which may exchange data such as a telecommunications antenna 108 or a Wireless Access Point (WAP) 360. The master unit 102 of the DAS telecommunication system 100 communicates with, i.e., sends/receives the RF signals to/from, each of the remote units 112 by an optic fiber cable 116. Inasmuch as the optic fiber cable 116 is highly efficient, such fiber cable is employed to minimize signal losses over large distances, e.g., greater than about eight hundred feet (800′). To further improve efficiency, optic signals may be carried or transmitted by multiplexing the optical signal. Alternatively, Wave Division Multiplexing (WDM) may be employed to improve throughput across the fiber optic cable 116. This feature will be discussed in greater detail hereinafter.
While the fiber optic cable 116 is capable of transmitting RF signals over large distances, i.e., without the need for amplifiers or repeaters, it is not capable of transmitting power. Accordingly, the fiber optic cable 116 is accompanied by a conventional metallic pair of copper wire cables 118 along its length. In view of the magnitude of the voltage transferred by the copper wire cable 118, i.e., three-hundred forty-five volts (DC 325 V), a sixteen (16) to twenty (20) gauge, Category 5/6, wire may be employed to convey power to the remote units 112 and/or to the telecommunication antennas 108. While the described embodiment illustrates a separate cable, i.e., fiber and copper cables 116, 118, for exchanging data and transmitting power, the optic fiber cable 116 and wire cabling 118 may be bundled in a single hybrid cable (not shown), i.e., contained within a common flexible plastic or elastomeric sheath. Furthermore, since the fiber, copper or hybrid cable transmits high voltage PET energy, e.g., DC 325 V, while providing a level of safety commensurate with much lower power systems, e.g., fifty-six volts DC 56 V, there is no requirement to protect the cables 116, 118 in an electrical conduit. Moreover, the hybrid cable or fiber/copper cables, 116, 118 need not be installed by a licensed electrical tradesman, e.g., an electrician.
The telecommunications antennas 108 comprise a plurality of micro antennas providing a combination of omnidirectional and directional coverage to blanket a space. Open areas, such as a square space 120 shown in
At least one remote unit 112 connects each of the telecommunication antennas 108 to the Master Unit 102 through the optic and copper cables 116, 118. As discussed above, each remote unit 112 is operative to amplify/attenuate/repeat the RF signals received from the BTS 104 through the Master unit 102 of the DAS telecommunication system 100. Each remote unit 112 includes a ground-hardened, conductive, outer casing 140 for containing and protecting the internal components of the remote unit 112. The remote unit 112 also includes band-specific linear amplifiers and IF filtering to effectively amplify the signals generated by the BTS carriers while blocking bands which fall outside the desired RF coverage.
In
While remote units of the prior art typically operate at a voltage level below about fifty-six volts (DC 56 V) in order to power a one-thousand Watt (1000 W) unit, the remote units 220 of the present disclosure operate at three-hundred forty-five volts (DC 325 V) to provide an equivalent level of power. Each micro-receiver 200R may include a transformer, or a DC-to-DC converter 250, for reducing the voltage from three-hundred forty-five volts (DC 325 V) to fifty-six volts (DC 56 V) to power each of the telecommunications antennas 108. A Power-over-Ethernet cable 170 may be used to transmit/receive data between the telecommunication antennas 108 and the micro-receiver 200R while using the same cable 170 for powering each of the telecommunications antennas 108.
In
The Media Converter 370 receives fiber optic signals from a conventional fiber optic cable 116 and converts the signals into conventional electronic signals. These electronic signals may then be conveyed along a wire/copper cable 118 to a target device, e.g., such as a canister antenna. Accordingly, the Media Converter 370 transforms data which can be transmitted over an optic cable 116 into data which can be transmitted over a wire cable.
In this case, the power received by the PET receiver 310 is converted into analog power for use by a Power-over-Ethernet (PoE) cable. r-Ethernet (PoE) cable 170 may be used to transmit/receive data between each of the WAPs 360 and the PET receiver 200R while using the same cable 170 for powering each of the WAPs 360. Accordingly, all of the WAPs 360, which can exceed 100 units in for many DAS systems 200, may be powered by a Power-over-Ethernet (PoE) cable 170 in contrast to running power to each of the WAPs independently.
PET-Powered Telecommunication System (MAS Embodiment)
In
Therein, power and data may be transmitted over large distances, i.e., far greater than a few hundred feet (more typical for the Macro Antenna System shown in
It should be appreciated that various technologies may be brought to bear on the power/data distribution system (PD2S). For example, Wave Division Multiplexing (WDM) may be used to carry multiple frequencies, i.e., the frequencies used by various service providers/carriers, along a common fiber optic cable. This technology may also be used to carry the signal across greater distances. Additionally, to provide greater flexibility or adaptability, a splitter (not shown) may be employed to split the fiber optic signal, i.e., the data being conveyed to the distribution box 520, such that it may be conveyed/connected to one of the many Remote Radio Units associated with the service providers making use/leasing space on the same tower/elevated structure 412.
Digital energy or Packet Energy Transfer (PET) technology, is employed on the first or upstream side S1 of the connecting interface/distribution box 520 while analog energy or power, i.e., conventional AC/DC power, is employed on the second or downstream side S2 of the interface/distribution box 520. In the context used herein, digital power is characterized by the delivery of discrete packets of energy conveyed on periodic or regular schedule over a conductive wire cable. In the described embodiment, the digital energy employed is high potential, e.g., at or about three-hundred forty-five volts (DC 345 V), significantly above a threshold established by Underwriters Laboratory (UL) which identifies a far lower threshold as a transition point/voltage for safe handling of a power circuit. That is, UL has established a threshold of sixty volts of direct current (DC 60 V) as the transition voltage wherein it is recommended that skilled/certified/licensed tradesman be employed to perform installation, maintenance and repair of electrical circuits carrying a voltage above this this threshold.
Inasmuch as digital power offers alternative mechanisms for safe handling and does not have an upper potential limit for the packets of digital energy delivered, PET technology provides an elegant solution for this leg of the PDS. Furthermore, since PET technology may be delivered over high gauge, low weight metal or copper cable, conventional Category 5 or 6 cable may be used on the first, or upstream side S1 of the PDS. Category 5 or 6 cable is universally carried by service technician, hence, such cable may be cut, sized and prepared for connection to an interface port in the field. That is, there is no need to special order a length of heavy, low gauge, copper cable to traverse the height of a cell tower 412.
The second, or downstream side S2 of the PDS is characterized by the use of analog power which may be carried by conventional direct or alternating current. However, before being conveyed to the downstream side S2 of the PDS, the digital power must be converted to a form which may be handled by tradesman having a far lower skill level. That is, upstream of, and prior to crossing, the interface/distribution box 520, a power converter 550 receives the periodically-conveyed energy packets and converts the same to an uninterrupted, continuous stream of current (e.g., DC 60 V). A similar Category 5 or 6 coaxial cable 560 may be employed on the second side S2 of the PDS, facilitating commonality of inventory and the attendant cost advantages associated therewith. In the described embodiment, a DC-to-DC converter 550 is shown inasmuch as the remote radio heads are powered by direct current. However, it should be appreciated that alternating current may be employed, hence a DC-to-AC converter may be employed.
Inasmuch as the connecting interface/distribution box 520 is oftentimes in region of high interference or may be subject to lightning strikes, the distribution box 520 is conductive and electrically connected to a grounded structure. Furthermore, inasmuch as components of the PD2S are equally vulnerable, they too may be housed/protected within the distribution box 520. In the described embodiment, at least the power converter 550 and a PET receiver 420R are housed within and protected by the interface/distribution box 520.
Referring once again to
The PET power distribution system 420 includes a PET transmitter 420T, a PET receiver 420R, the first side copper cable 530 and the fiber optic cable 540. Similar to the previous embodiments the fiber optic cable 540 may be disposed in combination with the copper or metal cable 540 to produce a hybrid cable. In the described embodiment, at least the PET receiver 420R and DC-to-DC converter 550 are disposed within the interface/distribution box 520. In the described embodiment, the distribution box 520 is mounted to the tower 412 and provides power to each Remote Radio Units (RRU) 420.
Additional embodiments include any one of the embodiments described above, where one or more of its components, functionalities or structures is interchanged with, replaced by or augmented by one or more of the components, functionalities or structures of a different embodiment described above.
It should be understood that various changes and modifications to the embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present disclosure and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.
Although several embodiments of the disclosure have been disclosed in the foregoing specification, it is understood by those skilled in the art that many modifications and other embodiments of the disclosure will come to mind to which the disclosure pertains, having the benefit of the teaching presented in the foregoing description and associated drawings. It is thus understood that the disclosure is not limited to the specific embodiments disclosed herein above, and that many modifications and other embodiments are intended to be included within the scope of the appended claims. Moreover, although specific terms are employed herein, as well as in the claims which follow, they are used only in a generic and descriptive sense, and not for the purposes of limiting the present disclosure, nor the claims which follow.
This application is a non-provisional patent application of, and claims the benefit and priority of, U.S. Provisional Patent Application No. 62/142,522 filed on Apr. 3, 2015. The entire contents of such applications are hereby incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62142522 | Apr 2015 | US |
