CZ2000553A3 - Long-distance network - Google Patents

Abstract

The remote communication network includes at least two switchers places (100) that are interconnected through the central communication system (702). Each Switch Point (100) it provides wireless coverage in at least one unit. At least two remote locations are located in each sector a are associated with a corresponding interconnect (100) via multipoint wireless broadband. Network advantageously includes at least one service node that is accessible from remote locations via switching points (100) and central communication system (702).

Description

Long-distance network

Technical field

The present invention relates to a metropolitan trunk network for telecommunications systems. In particular, the present invention 5 relates to the integration of a wireless point-to-point system operating in a millimeter microwave radio range with an intelligent metropolitan broadband central network to enable a number of improved voice, broadband data and "multimedia telecommunications services".

BACKGROUND OF THE INVENTION

Two-point narrowband, multi-point narrowband, and two-point broadband wireless systems are generally known in the art. Multipoint radio technology is also known '

technology that was generally used for narrowband communications, such as voice. Narrowband systems are typically systems that are capable of generating data at a rate of 1.544 megabits per second or less in a perimeter or channel only, while broadband systems are capable of generating data rates above 1.544 megabits per second per per circuit or channel. While narrowband multipoint systems were used for voice communications, multipoint systems were not generally applied to broadband telecommunications networks.

Current narrowband multipoint systems can combine a group of up to twenty-four channels at a rate of 64 kilobits per second together, which is then called the TI line. However, this T1 line is still considered a narrowband device when used to support many voice

3Q channels. Narrowband multipoint systems have also been used in Europe for voice telephony networks for several years.

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Two-point broadband technology is also well known. Point-to-point broadband wireless systems in the range of 37 Gigahertz GHz to 40 GHz (commonly referred to as 38 GHz) are used. When a 38 GHz broadband wireless link is established correctly, its performance is functionally equivalent to that of a fiber optic telecommunications network.

Fixed wireless technology is gaining popularity as a means of transmitting telecommunications services due to its low cost, quick installation and ease of operation.

The connection of two sites by point-to-point wireless service usually consists of installing roof antennas on top of two buildings with associated interior equipment. Physical wires do not need to be interconnected between buildings, which represents a significant advantage 15 over copper or fiber optic technology. Bringing fiber optic or copper wires to buildings entails considerable work and additional costs associated with re-docking, obtaining permits and the like. Because of the deployment of broadband fixed wireless systems in most

There is no need for building structures in cases, so it is much faster and cheaper to install such systems than connecting the last mile by traditional methods in metropolitan telecommunications networks.

The current 38 GHz fixed wireless technology has a number of features that make it an attractive commercial telecommunications transmission medium. 38 GHz wireless technology provides a high-frequency broadband path for voice, data, multimedia and video transmission. Current technology allows you to connect distances of up to five miles (approximately 8 km). Because every millimeter microwave propagation «00» 00 0000

0000 0 0 0 «0 · 0 · 0 0 0 0 0« 0 0000 00 00 is subject to rain degradation, the actual distance is a function of the geographical area or rain region. In climates where heavy rainfall is common, shorter bonding distances may be required to achieve performance and availability equivalent to fiber optics.

Radio millimeter wave propagation at 38 GHz generally requires non-inclined transmission on the line of sight. In practice, small diameter antennas are mounted on roof tops of office buildings, and in some cases these are in the windows of office buildings. These antennas typically have a diameter in the range of 12 to 24 inches (about 30.5 cm to 61 cm), although smaller antennas may also be used.

Manufacturers report a Mean Time to Failure (MTBF) statistically exceeding 10 years for radio and modem components, suggesting that hardware is highly reliable. Therefore, today's 38 GHz fixed wireless technology is ideally suited for high-availability, broadband, point-to-point commercial voice and data applications with capacities ranging from 1.544 megabits per second (TI) to 45 megabits per second (DS3).

One example of a typical wireless two-point broadband commercial application is the interconnection of multiple service channels in a university or group local area network (LAN).

Another such application is the metropolitan long-distance network. Here, more university or group LANs within the same city are 25 connected via wireless devices at 38 GHz. Allocated access to inter-switchboard carriers (IXCs), Internet Service Providers (ISPs), and other alternate access arrangements are common point-to-point business applications for 38 GHz wireless links. In the 38 GHz range, cell operators and ³⁰ Personal Communication Services (PCS) can deploy highly available

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Wireless point-to-point technology is also used to provide missing critical protection channels and other point-to-point paths where expansion from a fiber optic network to sites that are not fiber-optic is required. Eventually, the public switched telephone network (PSTN) connection is becoming increasingly popular for providing local dialing tone to competing local exchange carriers (CLECs), using point-to-point wireless technology at 38 GHz.

Giant. 2 illustrates a basic point-to-point wireless device providing customer connectivity with services. This connection will support broadband (data, video, etc.) and narrowband (voice) applications.

The customer building is shown in the figure and designated as building 200, which may include a plurality of tenants. This building is connected to another building

202, which includes a switch 203 of telecommunications networks. These buildings are connected via a wireless link between two antennas on the roof top: one antenna 204 at the customer building 200 and the other antenna 205 at the building 202 that includes a switch 203. The bandwidth of this connection could be up to 28 TI circuits or DS3 (45 megabits) per second).

The switch 203 is connected to a PSTN 206, or other public switched telephone network for local service, and to long-distance service networks 207. The switch 203 is also capable of providing Internet access call 208.

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Giant. 3 is a representation of a 38 GHz FCC spectrum assignment scheme consisting of a total of 14 channels. Each channel has a bandwidth of 100 megahertz (MHz). Each 100 MHz channel consists of two 50 MHz sub-channels, one sub-channel for transmission and the other sub-channel for reception. The two 50 MHz sub-channels are separated by the 700 MHz spectrum. As shown in Fig. 3, sub-channel 1A is 50 MHz wide and is a broadcast channel, while. the sub-channel 1B is 50 MHz wide and is the receiving channel.

Sub-channel 1A is separated from sub-channel 1B by 700 MHz. This band diagram provides 14 channels (1400 MHz or 1.4 GHz) of the spectrum in the FCC assigned range of 38 to 40 GHz.

Figure 4 illustrates the basic spectrum management problem associated with the use of point-to-point wireless systems in the metropolitan area. Since the buildings are very close to each other in the metropolitan area 15, broadcasting information over wireless links may overlap, which may make it impossible to use the same channel (1A / 1B) in neighboring systems. In this figure, one antenna from one building transmits its signal to the antenna of the designated receiver, but part of this signal is also received by the antenna on the adjacent building.

Such signal interference is referred to as interference of shared channels.

FIG. 4 is a host building 401 comprising a

'. switch 402 connected via four roof antennas 403A, 4Q3B,

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403C and 403D, respectively, with distant buildings 404A, 404B, 404C and 404D, each having their own corresponding roof antenna. Between these buildings, a schematic representation of the spectrum used by each of these point-to-point wireless systems is shown. The closer the buildings come together, the more the transmitted signals overlap between buildings. For

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To avoid interference with shared channels, as described in the previous paragraph, different channels must be used to connect buildings that are in close proximity. For example, channel 1A / 1B is used for building 404D and channel 2A / 2B is used for building 404C. Although channel 1A / 1B partially overlaps the transmission of channel 2A / 2B, the use of different frequencies (channels) by these two systems provides protection against common shared * interference. channels. Thus, an antenna of one building may transmit part of its signal to the wrong reception antenna, but each system is tuned to a different frequency and transmission from neighboring systems using different frequencies is ignored.

The frequency management technique depicted in FIG. 4 prevents interference of shared shared channels in wireless networks located in dense urban areas, but using FCC channels to prevent shared shared channel interference does not maximize the transmission rate of the allocated spectrum and is therefore ineffective. A solution to this problem is therefore needed.

Giant. 5 illustrates another spectrum management problem associated with point-to-point systems. Building 501 is connected to building 502 via channel 1. Building 503 is connected to building 504 via channel 2. Fixed connection lines 505, 506 represent the wireless transmission that is intended. However, since the transmitting beam has about 2 degrees in the source, there may be a signal

·. received by other systems that are not planned, but may be within the transmission beam of the original system. The dashed line 507 represents a case in which the system in building 504 incorrectly receives a system transmission from building 501. If two different frequencies are used, then the shared shared channels will not be disturbed. Again, frequency management in point-to-point wireless networks • 4 »4 • * ♦ · 4 ·

4 4 4 4 · * ·· · * ·· requires the use of many channels to prevent interference rather than to allow the use of spectrum to achieve additional bandwidth.

The roof space is expensive and in many cases there are limitations on the number, size and position of the antennas located on the roof. Because point-to-point systems use separate antennas for each wireless connection, space becomes a limiting factor on the roof tops of buildings. As the number of point-to-point systems placed on a building increases, the number of systems that can be used does not only limit spectrum management requirements, but the number of these systems is also limited by the physical space available for each antenna on the roof. Thus, a solution is required that allows the capacity of the wireless network to be expanded and thus the number of users without correspondingly increasing the number of antennas on the roof superstructure.

Two-point systems provide users with what is called continuous connection. Continuous connections are always ready (connected and active) waiting to transmit information, continuous wireless connections use the allocated spectrum, which once assigned, is unavailable to other users. Thus, point-to-point wireless systems are suitable for applications involving continuous or long-range transmissions. Point-to-point systems support inefficiently variable bit rates or burst data services in which bandwidth requirements are not constant but, on the contrary, variable. The bandwidth used by point-to-point systems for variable bit rate applications is excessive, as each system utilizes a dedicated channel on a perpetual (continuous) readiness basis regardless of the amount • 9 9 9 • «9«

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9 »9 9 9 · ·· 9999 99 99 information or duration of transmission on the link. Thus, a solution is required for a more efficient use of spectrum for burst data services, such as data transfer from LAN to LAN.

It is therefore an object of the present invention to provide a full-fledged local metropolitan broadband telecommunications network infrastructure capable of supporting enhanced voice and data services.

It is a further object of the present invention to utilize wireless spectrum as a major activator of access to a local metropolitan broadband telecommunications network offering improved voice and data services.

One object of the present invention is also to maximize the utilization of the allocated spectrum available in local metropolitan broadband telecommunications networks.

It is a further object of the present invention to overcome the spectrum management limitations associated with the use of point-to-point fixed wireless telecommunications systems.

It is also an object of the present invention to enable the use of moha channels to control additional network capacity in local metropolitan broadband telecommunications networks.

One further object of the present invention is to minimize the number of wireless telecommunications systems required on roof tops to provide access to local metropolitan broadband telecommunications networks.

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SUMMARY OF THE INVENTION

According to one embodiment of the network according to the present invention, the remote communication network comprises at least two switching points that are interconnected by the communication central system. Each switching point provides wireless coverage in at least one sector. At least two remote sites are located in each sector and are connected to a corresponding switching point via a point-to-point "broadband wireless system". Preferably, the network comprises at least one serving node that is accessible to remote sites via switch points and a central communication system.

According to another embodiment of the network according to the present invention, a broadband local metropolitan telecommunications network provides a fixed broadband wireless connection circuit accessible to a plurality of subscribers. The subscribers are equipped with a subscriber radio unit operating at a frequency corresponding to the sector of the cell in which the subscribers are located. At least one of the participants has a quantity

20 includes associated customer building equipment and includes means for performing a statistical multiplex between the plurality of customer building equipment of the subscriber radio unit. The network includes a number of switching points that are connected by a central • 25 Sonnet communication system. The switching sites include a plurality of switching unit radio units that operate at an optional frequency with at least one radio unit corresponding to a cell sector. The switching sites further comprise means for dynamically allocating communication bandwidth among the plurality of subscribers

5Q within each of said sector cells. Preferably, the network comprises a plurality of data service nodes that are connected to a central communication system and which are accessible to subscribers via switch points and a central communication system. The network further comprises a central operating node which is connected to each of said switching sites via a control network and provides remote access and control of the switching sites as well as remote access control of subscribers to the data serving nodes.

These and other features, objects, and advantages of embodiments of the network of the present invention will become more apparent from the following detailed description of illustrative embodiments of the invention with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a schematic diagram illustrating a local 15 metropolitan broadband telecommunications network using fixed wireless point-to-point systems operating at 38 GHz to provide customer access to the local metropolitan broadband telecommunications network;

Fig. 2 is a schematic diagram illustrating a typical point-to-point arrangement known in the art for providing customer access to telecommunications services through a switch;

_9C . Fig. 3 is a schematic diagram illustrating a spectrum allocation scheme for 38 GHz, with 100 MHz channels divided into 50 MHz sub-channels for transmitting and receiving signals, each transmitting and receiving sub-channel being separated by a 700 MHz spectrum;

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Giant. 4 is a schematic diagram illustrating point-to-point fixed wireless systems deployed in a prior art switching network configuration in which the relationship between switch and wireless systems of customer buildings is one-on-one. The overlap regions illustrate the phenomenon of common shared channel interference that occurs in point-to-point wired wireless networks;

Fig. 5 is a diagram illustrating another phenomenon of common shared channel interference that occurs in two-point fixed wireless systems of the prior art;

Fig. 6A is a diagram illustrating a fixed wireless point-to-point implementation in which there is a one-to-many relationship between a switching site and customer systems within a sector used according to the present system;

Fig. 6B is a block diagram further illustrating the switching point of Fig. 6A as used in the network of the invention;

Giant. 7 is a diagram illustrating a local metropolitan broadband telecommunications network according to the present invention utilizing 38 GHz multipoint fixed wireless technology to provide customer access to a central communications system network and various telecommunications services;

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Giant. 8 is a block diagram of one embodiment of a subscriber system used in the system of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

1, Network topology

The network of the present invention employs a fixed wireless microwave scheme that allows a one-to-many relationship between switching systems and remote systems located in customer buildings. This technology, called multiple access or multipoint, can support traditional voice and data telephony services as well as commercial and resident broadband multimedia services by combining improvements in efficient use of spectrum (and hence available bandwidth) with improved intelligence in the metropolitan long distance network.

Giant. 6A illustrates a multipoint system characterized by a one-to-many relationship between switching system and radio systems on customer buildings. In Fig. 6A, switching point 601 is provided with antennas 602, 603 and 604.

Antenna 602 transmits to sector 605, which covers the physical space occupied by many subscriber buildings 606, 607, 608 and 609. Antennas on buildings 606, 607, 608 and 609 in sector 605 all communicate with one antenna 602 switch point for sector 605. Sectors can be from 15 to 90 degrees wide. All of the buildings in the sector generally use one channel, so canceling shared channels is no longer a problem for buildings in the same sector.

To prevent interference from the shared shared channels at the edge of the sectors, the switch point 601 allocates frequencies

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neighboring sectors that are considerably separated from each other. For example, channel 60A may be allocated to sector 605 to which antenna 602 transmits, and channel 610 may be assigned to sector 610 to which antenna 604 transmits. Thus, multipoint systems allow full utilization of each channel allocated in the information transfer sector, as opposed to spectrum management requirements for point-to-point systems, which require the use of many channels in the same geographical area only to prevent interference from shared channels.

Giant. 6B illustrates an exemplary embodiment of a switch site 601 for use in a network according to the present invention. The antennas 602, 603, ..., 60n correspond to the frequency channels. Generally, one frequency channel is allocated by the corresponding cell sector 605. However, in cases where additional bandwidth is required, it is possible in the network of the present invention to allocate multiple channels to one or more cell sectors. Each antenna preferably includes a corresponding radio unit 620 of the switch point. To avoid signal loss associated with coaxial lines and waveguides at 38 GHz, these radio switch points 620 are preferably coupled to the corresponding antenna as an integral unit mounted on the roof top or tower.

The switch site also includes switch site indoor units 622 that are coupled to switch site radio units 620 via interconnection lines 624. Such interconnection line 624 is a broadband connection, preferably in the form of a fiber optic connection. The Hub IDUs are connected to one or more of the Hub Control Units 326 which control the operation and data of the switch point. transmission within the switch site 601. An interface 628 of the central communication system is also included to allow connection and data transmission to the network central communication system.

Giant. 7 illustrates an embodiment of the network of the present invention in a commercial metropolitan network using 38 GHz multiple access wireless technology. The network includes a broadband central communication system 702 that can be implemented using fiber optic, copper wire, or wireless technology. The large squares located on the circle represent multipoint switch sites 704, each of which covers at least one cell sector 706. In a commercial urban environment, cell sectors 706 are spaced such that bandwidth is directed to geographic locations with appropriate building density (customer). Once on the central communication system 702, customer traffic is routed to any number of network nodes providing data services. Examples of such service nodes are local switchboard switch 706, remote switchboard switch 708, Internet access points 710, and video service points 712.

The network of the present invention also includes at least one central traffic node 712 that is connected to each of the switching points 704 via a control network 715, such as a frame switching network.

The 38 GHz multipoint wireless network architecture generally consists of 714 cells with a diameter of 3 to 5 miles (i.e. approximately

4.8 to 8 km, which corresponds to link lengths of 1.5 to 3 miles, which is approximately 2.4 to 4.8 km). Each cell 714 consists of a plurality

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sectors 706-1. 706-2, ..., 706-n, with a sector width ranging from 15 to 90 degrees. The switch site 704 is located at the center of each cell, and a plurality of remote subscriber systems (subscribers) 716, located in customer buildings within the sector, communicate with the radio equipment of the switch site to establish wireless links. The bandwidth within a given sector is allocated among remote subscriber systems provided in that sector by the corresponding switching point

704. A sector can utilize the full bandwidth of a single allocated channel, or multiple channels can be stacked in a sector to meet all customer bandwidth requirements. When multiple channels are used, an additional radio unit 620 and an antenna for that sector are added to the switch site 704.

Allocating optimal sector width is not a trivial problem. One design goal is to minimize the cost of efficient radiated power (ERP). Narrower sectors provide higher antenna gain, so less energy is needed to achieve a given ERP. However, each sector requires its own radio system, so narrow sectors increase the cost of equipment required to cover a given geographical area.

In the final analysis, the design of the switch point is a function of overall customer capacity and geographic requirements. division of customer places.

They are preferably in a point-to-point metropolitan network according to «

In the present invention, the switch points 704 are connected to the central communication system 702 by means of optical fibers or high capacity microwave radio means in a SONET-type loop arrangement. Internet nodes such as remote switch switches 708

access points 710, PSTN switches 706 and video service points 712 are interconnected into an optical fiber loop, in some cases through co-location with the switch points. Thus, once customers are connected to the network via wireless access lines, any and all services supported by different service nodes will be accessible to them.

This network access requires the transmission and routing capability of the central communication system to allow connection between many customer sites and between customer sites and network serving nodes. The asynchronous transfer mode (ATM) is a preferred transport layer protocol for the metropolitan network architecture of the present invention. It can also be envisaged that, over time, more traditionally oriented connection or synchronous telephone transport protocols will be used as a transition to full ATM mode networks. For this reason, both ATM (OC-3c) and STM (DS-3) interfaces are preferably incorporated between switching points 704 and central communication system 702.

2, Wireless ATM

This network architecture uses asynchronous transfer (ATM) mode as the primary means of network transmission. ATM is a packet transmission technology that organizes information into cells. Cells have headers and useful data. The header describes what type of data is in useful data and where the data should end. The cells spread through the network in different ways and may arrive out of order at the destination. The header information contained in the cell allows the correct order of the cell to be reconstructed before being passed to the customer building equipment. ATM cells • 0 0 0 0 0 * · 0

0 0 0 0 0 · * · 0

0 · 000 0000 00 00 0000 00 00 can transmit many standard telecommunications voice, data and video services by incorporating data into useful data. ATM is thus able to integrate voice, data and video in one telecommunications transmission network.

A key architectural element of the network of the present invention is the use of ATM in a multipoint wireless transmission system (air interface). Customer specific services (Ethernet, frame transmission, DS-1, DS-3,

ISDN, voice) are embedded in ATM payload between subscriber systems 716 and switching point 704. Thus, the services that are most efficiently handled by the cell-based protocol are retrieved from the terminal ATM transmission in the network, while services that have to be grouped into time the channels on the central communication system are at the switching point 15

704 multiplexed with time division. In any case, the transmission of all services via ATM over the air allows an important functional advantage of bandwidth on demand.

Wireless modulation using modulation techniques such as QPSK and 4FSK provides an effective data rate of one bit per hertz per second. Because the 38 GHz spectrum is allocated in 50 MHz duplex channels (i.e., 50 MHz spectrum in each direction for a total of 100 MHz per allocated channel), the maximum point-to-point data rate of current fixed wireless technology is 45 Mbps, or DS-3. A higher order of modulation techniques such as 16 QAM and 64 QAM, together with an improvement in overall system gain, will provide data rates of 4 to 5

5Q bits per hertz per second or greater. This will result in a substantial increase in the available bandwidth per channel. So data • «··

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0000 OC-3 speeds (155 Mbps) per channel and sector and above are achievable at 38 GHz. Spectra with efficiency ranging from 6 to 8 bits per hertz per second are expected. Multi-sector, multi-channel cells supporting total data rates of

5. Gigabits per second available Bandwidths are readily available based on relatively conservative techniques. Less conservative constructs will provide higher cell capacities.

4. Bandwidth on demand

Because data is incorporated into cells for transmission over a wireless network, it is possible to use the radio spectrum much more efficiently than otherwise would be possible in wireless applications not using ATM. This is due to a technique called statistical multiplex. The statistical multiplex takes the advantage of the random origin of the data transmission in the system and the fact that not all users require bandwidth at all times. The statistical multiplex allows cells containing data originating from different users to be transmitted via the minimum required spectrum. In this sense, users share the allocated spectrum in the wireless ATM network, and the aggregate bandwidth requirement of all users in the system is served by the spectrum that is available in the system at any given point in time.

This results in statistical gain in data capacity, allowing wireless telecommunications network operators to overwhelm subscribers on the assumption that not all users at a given subscriber location (such as a multi-tenant office building) will require all the capacity allocated to that location at all times. · »· ♦« ·· «· moments. Subscriber congestion ratios (statistical gain) of up to 10 to one (10: 1) are possible for links where most information is transmitted in short bursts (burst data), as is the case with LAN-LAN communications. Statistical Gains 2; 1 or 3: 1 are more common for networks in which the traffic mix is much more inclined to voice or other services requiring point-to-point connections over a network (circuit) for the duration of a communication session.

ATM cell headers also contain parameters that allow the prioritization of individual cells. Thus, the highest priority cells are transmitted across the network instantly, while the lower priority cells may be delayed until the higher priority cells are switched. This ATM attribute enables to support with changing quality (quality) of service or otherwise QOS. When this priority system is used in conjunction with a statistical multiplex, it allows information to be transmitted over the wireless network very efficiently. For example, a large file may be partitioned into cells and transmitted over the network with other cells of smaller files spread over a packet stream. Therefore, small files do not have to wait until the transfer of a large file is complete, and the network works more efficiently overall.

According to the invention, it is possible to utilize dynamic bandwidth allocation between subscriber systems 716 within a given sector 706. The current requirements for high bit rate bursts of the subscriber systems 716 are thus met by utilizing bandwidth in sector 706 that is not currently used by other subscribers . This is done through variable allocation to slots (multiple access with time division or * 44 «4 4 · 4 4 4 ·· ♦ 44 44 4444 ··« 4

TDMA) or frequency (FDMA multiple access) on demand, or through a combination of both multiplex techniques (On Demand Multiple Access or DAMA).

⁵ When these techniques for dynamic bandwidth allocation between the building sector combined with ATM statistical multiplexing (flooding participants) bandwidth allocated to customers within individual buildings, is the result of a huge increase in capacity of information transmission Wireless' 10 spectrum utilized in the networks of the present invention. Capacity is further increased using high efficiency modulation schemes such as 16 QAM and 64 QAM.

5, Switching Architecture 15

The system of the present invention employs a deployment strategy, known as switching, that concentrates one end of many wireless links on the roof superstructure of one building or switching site. Each switching point 704

20 can connect to many remote radio subscriber systems 716 using wireless links. The switching points 704 in the metropolitan area may be connected to a circuit, network, or other central network topology by wireless means, fiber optic means, or other high capacity telecommunications equipment. Switching points 704 are equipped with ATM switching «

or a TDM multiplexing device for bridging wireless links through the central communication system 702 to establish a connection between subscribers or to connect subscribers to other sites on the network to access services. Through switching, the network is utilized with a significant increase in efficiency

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the range of wireless access links, as well as providing access to a variety of voice, data and multimedia services.

The switching architecture of the present invention 5 is applicable to both point and multipoint fixed wireless systems. In a point-to-point wireless system, each switching site carries one antenna for each link that connects to the central communication system network. Thus, the center-top space represents a limitation in the number of antennas (and therefore ¹⁰ links on the network) that can be carried by a single switching point using point-to-point fixed wireless systems. Giant. 1 illustrates an embodiment of a network architecture using 38 GHz point-to-point wireless telecommunications systems in which wireless devices connect customer sites to a metropolitan central communications network. The system utilizes a point-to-point system in which communication takes place between the switch point 100 and specific buildings 102 or groups 104. The central communications network consists of high-capacity telecommunications transmission devices 106 connecting switch points to a circular arrangement, each switch point connecting individual buildings or group points via wireless connection on the last mile (in the last segment).

For multipoint fixed wireless systems, fewer antennas at the switch point provide connections to customer buildings in a sector ranging between 15 and 90 degrees, which includes many customer buildings. In any case, the switching architecture provides efficient access to the network of the central communication system, allowing 30 * * ·

4 4 4 · 4 4

404 »3 • ·

4444 communication between subscribers and allows subscribers to access data services connected to the network.

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6. Equipment of remote subscriber systems and support of services

In the system of the present invention, subscriber systems 716 may take the form of a single subscriber, a multi-user building system, or even customer groups. Giant. 8 illustrates one embodiment of a subscriber system for use with a multi-user system in a building.

As seen in Fig. 8, the antennas 802 are integrated with radio transmitters / receivers in compact sealed outdoor units (ODUs) 804 for installation on the roof top of a building. These ODUs are preferably secured by standard 4 inch (approximately 10 cm) mounting columns for quick and inexpensive installation and unobtrusiveness. The outer units 804 are connected to the inner 15 units (IDUs) 806, typically located in a common space inside the building, through an interconnection line (IFL) 808 consisting of either a coaxial cable or an optical fiber.

The use of optical fiber in IFL 808 provides a significant advantage in installations where the conduit inside the building is already tightly occupied by telecommunications equipment and there is little space to pull a new cable. This is a common problem with similar installations. Because the fiber is much thinner than the coaxial cable, it is much easier to pull through existing conduit tubes than that of the coaxial cable, which in turn makes installation work considerably faster and cheaper than conventional cases.

Another advantage of using fiber in IFL 808 is related to signal loss between IDU 806 and ODU 804. Physical The properties of a coaxial cable limit signal propagation in most cases at less than 1000 feet (approximately 305 meters). This represents a restriction on the distance between ODU 804 and IDU 806 in the building. Since a common space created for telecommunications equipment (including IDU 806) is in most commercial office buildings located in the foundations and ODU 804 is mounted on the roof, this presents a problem for _the installation of larger buildings of 15 storeys or more.

The fiber optic cable does not have such a distance restriction between 10 IDU 806 and ODU 804. Thus, the installation is not adversely affected by the location of the common area for telecommunications equipment in buildings.

Indoor units 806 are used to interface with customer equipment (CPE) 810 in buildings. Preferred embodiment 15 of indoor unit 806 includes a frame with slots for receiving line services 812 of specific services. Line cards 812 are physically inserted into the frame when customers are installed and are activated via software commands from a centralized network operation center.

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Line Cards 812 are designed to support specific telecommunications services (DS-1, DS-3, ISDN, Frame Transfer, Ethernet, Frame Ring Network, ATM, and the like). The line cards 812 are further coupled to an interface plane for converting protocols to ATM for transmissions to a switch site, and from ATM to '25 specific service protocols for transmissions from a switch site. The frame may preferably carry 10 to 20 line cards 812, each of which may provide multiple inputs for interconnection with the CPE 810. For example, a conventional DS-1 line card allows connection 4.

DS-1 line (4 x DS-1) per card. Line Cards are cheap,. , so increase the cost of adding customers to the network as soon as you are the basic equipment of the remote system on site in the building is quite low. Once installed, the services provided by the line cards 812 may be locally activated, or preferably remotely activated via commands generated by the central traffic node 713 (see Fig. 7), which are transmitted over the network.

In this way, the indoor units effectively meet the requirements for telecommunications services, especially in terms of price. Most small to medium commercial θ office buildings can be supported by 10 to 20 card frames as described above. In very large buildings, two or more IDUs may be interconnected in a closed-cycle manner to extend the number of available service interfaces, and may be installed on different floors where common areas and main distribution frames may be located to serve the customer. The present invention also provides very small, inexpensive indoor units with fixed service interfaces for serving small office / home office (SOHO) and home customers. Rather than using the frame architecture θ and the connection planes, these small IDUs are rather fully integrated sealed units manufactured at low cost to support a predefined set of services. An example of a small IDU of this type could provide an interface for multiple 64Kbps voice lines and an ISDN or Ethernet input to connect to a remote office LAN.

7, Operating Instructions

In addition to improved spectrum utilization efficiency and q resulting in increased bandwidth, substantial savings can be achieved with multipoint radio technology at 38 GHz * ·· • 0 · * ·· «0« • 0 0 · 0 0 • 0 0 0 0

0 * 00 0 * 00 Operating and equipment costs. The complexity of the operation is eliminated by replacing many of the antennas on the roof top of the interconnection site with multipoint antennas of the interconnection site, thus similarly reducing installation costs. Once the switch point 704 is installed, adding network customers becomes the subject of installing subscriber systems 716 in subscriber buildings within the covered sector 706. This is different from the requirement to design and install equipment supporting the two ends of each link, as is the case with the current point 38 GHz wireless technology.

Also, service provisioning and configuration changes are remotely controllable through software-definable service attributes downloaded over the network to subscriber systems located in customer buildings.

Services are provided, monitored, modified and managed from a central network operations center by technicians with appropriate authorization. The system software enables remote provisioning of services from the switch point to the end user service interface card in the remote subscriber system.

8. Services

The network of the present invention can support any and all of the services supported by wired telecommunications technologies. These services include two in

broadly defined categories: traditional telecommunications services and emerging broadband multimedia services.

Traditional telecommunications services for the commercial market 30 include: (1) voice local and long distance services, (2) • 0 0 • · ·· 0000

0 0 0 • 0 0 0

00 point-to-point dedicated devices at DS-1, nx DS-1 and DS-3 speeds for voice and data, (3) switched data services such as 56 kbps and frame rate, and (4) high-capacity point-to-point data devices operating at OC-3 speeds and higher.

The emerging broadband multimedia services supported by the network of the present invention include high-speed Internet access, browsing and provision of websites and information services, services

LAN-LANs such as Ethernet and framing a circular network, and video services such as desktop video conferences, commercial video programs related to business, and video training on demand (distance learning). Wireless customer network access links are provided at essentially any data rate to meet the bandwidth requirements of such services.

Household customers are included with services that include a subset of the above services for telecommunications and small office / home office (SOHO) applications. The service package for these customers may include local and long-distance telephone services, high-speed Internet access for information services and e-mail, and optional video programs. Network access can also be provided at any speed to these home customers.

ATM Quality of Service (QOS) parameters can be used to support broadband multimedia data services based on usage. For example, a customer can subscribe to a network connection with a 2 Megabit Interconnection Information Rate (CIR). The manager in this customer's ATM cell should guarantee 2 megabits of true throughput • 999

9

9 9 9 9 9 99 99 99999 9

9 9 9 9 9

9999 99 «9 every time the customer requests this amount of bandwidth on the network. When these two megabits of network capacity (spectrum in a multipoint wired wireless network) is not used by this customer, they are accessible for other transmissions on the network.

ATM QOS parameters can be used to provide varying throughput levels on the network, allowing operators to set prices for compliance with these throughput levels. For voice services that are particularly intolerant to delays inherent in the unequal cell transfer, persistent virtual circuits (PVC) provide immediate passage at predefined data rates. PVCs use a constant fixed bandwidth in the network each time there is a request for this service. Although cell retention delays are measured in milliseconds, the accumulated effect of such delays can be detected by the human ear. PVCs overcome this problem in ATM networks by effectively creating a point-to-point path through the network over which cells are transmitted in turn. Basically, the PVC is a switched connection through an ATM network. In fixed point multipoint networks, the bandwidth is allocated on a permanent basis between the subscriber system and the switching point for the duration of the voice call.

Additional ATM-based services are provided using Switched Virtual Circuits (SVCs) that allocate bandwidth to user traffic according to a hierarchical priority scheme ranging from guaranteed data rates to data transfer based on available capacity. SVCs most effectively support variable bit rate data services (data bursts), such as LAN communications, with QOS parameters used for priority (criticality) passage management ) data and cost of service to the customer.

In the network of the present invention, event data for 5 billing is collected and stored in the system based on the type of service provided to the customer.

Billing of data services may take into account the time of day when the service was provided, network resources used by the customer (eg peak data rates, persistent data rates, number of packets / bytes transmitted), service quality provided, number of packets lost due to network congestion, or other network transmission errors, and other factors not normally considered in the billing algorithm for traditional telecommunications services. For voice services, the billing data is collected from the conventional detailed call record record (CDR) format 15 via switchgear deployed across a network.

The multipoint broadband metropolitan network of the present invention will support a wide range of future business and personal telecommunications services, such as automotive data applications using on-board computer systems that integrate city and highway maps with global positioning system data and local traffic information. Collision avoidance radar is another suitable automotive application. In addition, multipoint networks can support 25 PC applications with wireless broadband connectivity, including personal digital assistants, portable web terminals and group mobile LANs.

Claims (5)

PATENT CLAIMS A long-distance communication network, comprising: at least two switching sites, each switching site being adapted to provide broadband wireless communication with a plurality of subscribers in the corresponding sector; at least two remote locations, each remote location corresponding to one of said sectors, each sector comprising a plurality of subscriber locations and each of said subscriber locations further having a plurality of subscribers, said network being adapted to allocate bandwidth dynamically between said plurality of subscribers and said network further adapted to perform a statistical multiplex between said plurality of subscribers at each of said subscriber locations; a multipoint broadband wireless system, wherein each remote site is connected to a corresponding switching site via said multipoint broadband wireless system, and said multipoint wireless system incorporates data into ATM cells for transmission through the wireless system; a communication central system adapted to interconnect said at least two switching points, said communication central system allowing communication between said plurality of subscribers in each of said corresponding sectors; and a plurality of data service nodes associated with said communications central system to provide access to data services for said plurality of subscribers via said at least two switching points. V • · V V V * * t t t t t t t t A remote communication network according to claim 1 1, further comprising at least one service node operatively connected to at least one of said switching points. A remote communication network according to claim 1 2, characterized in that said at least one service node comprises at least one of an Internet service service node, a remote telephone service node, a local telephone service node, and a video service service node. A remote communication network according to claim 1 1, wherein at least one of said at least two remote locations comprises: 15 an outdoor unit, said outdoor unit comprising a radio receiver and a transmitter operably connected to the antenna; a plurality of indoor units, said indoor units being operatively associated with a plurality of customer units 2Q equipment in the building; and a coupler, said coupler linking said outdoor unit with said plurality of indoor units, said radio transmitter and receiver supporting a plurality of said customer equipment in a 25 building. . A remote communication network according to claim 1 4, further comprising means for statistically multiplexing said radio units between said plurality of customer equipment in a building. 0 0 0 0 0 00 00 000 000 A remote communication network according to claim 4, characterized in that said indoor units comprise: a frame, said frame having receiving means for 5 plurality of line cards; and a line card, said line card providing a specific service interface between said frame and customer equipment in the building. A remote communication network according to claim 1 6, characterized in that said line card can support an additional indoor unit in a closed cycle configuration. A remote communication network according to claim 1 25, characterized in that the interconnection line is an optical fiber line. A remote communication network according to claim 4, characterized in that the remote location is located in a multi-story house and the indoor unit is installed on a plurality of floors of the house. A remote communication network according to claim 1 1, characterized in that at least one of said at least two remote locations comprises integrated 25 unit providing selected services for customer equipment in the building. A remote communication network according to claim 1 1, characterized in that a multipoint broadband wireless system in each said The 30 switch point includes: ** ** · · · · * · 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 a first radio unit operating at a first selectable frequency and providing coverage in a first sector; a second radio unit operating at a second selectable frequency and providing coverage in the second sector, said second sector substantially adjacent to said first sector; and means for frequency selecting said first selectable frequency and said second selectable frequencies from a plurality of available frequencies such that said first and second selectable frequencies are considerably separated, thereby minimizing interference to the shared channels. A remote communication network according to claim 11, further comprising at least a third radio unit operating at a third selectable frequency, said third radio unit providing additional coverage in one of said first and second sectors, wherein said frequency dial means further selects said third selectable frequency such that that said first, second and third frequencies are considerably different. A remote communication network according to claim 1 11, characterized in that said network comprises a plurality of adjacent and non-adjacent sectors, said frequency dialing means reusing said available frequencies on said non-adjacent sectors. The long-distance communication network of claim 1 1, characterized in that said communication center system and said broadband ftft ft ft ft ft ft wireless each support a packet-based data transfer protocol. A remote communication network according to claim 1 14, wherein said 5 packet-based transmission protocol is an asynchronous transfer mode. A long distance communication network according to claim 14, characterized in that said 10, the packet-based transmission protocol for communication from the central system to the switching point includes both an asynchronous transfer mode and a synchronous transfer mode. The long-distance communication network of claim 1 16, characterized in that said packets Ί 5 are ATM packets comprising a header portion and a payload portion, said header portion including a service quality parameter, and wherein said network further comprises means for allocating system bandwidth according to said service quality parameter, 18. A broadband local metropolitan telecommunications network adapted to provide fixed broadband wireless local access, comprising: 25 a plurality of subscriber systems, each of said subscriber systems comprising a subscriber radio unit, said subscriber radio unit adapted to operate at a frequency corresponding to a sector of the cell in which said subscriber system is located, at least one of The 30 subscriber systems have a number of associated customer equipment in the building and include means for 000 0 * 0 0 000 00 0 0 0000 performing a statistical multiplex between said customer equipment in the building and said radio unit; a plurality of switching points, said switching points being interconnected by a central communication 5 Sonet type system; said switching sites comprising a plurality of switching site radio units, said switching site radio units operating at an optional frequency with at least one radio unit corresponding to a cell sector, said number of switching sites comprising 10 means for dynamically allocating communication bandwidth between a plurality of subscribers within each sector cells, and wherein said plurality of switching sites communicate with the at least one radio unit via the included data transmitted as 15 ATM packets; a plurality of data serving nodes, wherein said serving nodes are connected to said central communication system, and wherein said subscribers access said data serving nodes via said switching points, and 20, said central communication system; and a central traffic node, said central traffic node connected to each of said switching sites via a control network and adapted to provide remote control of said switching sites and remote control of said subscriber access to said service nodes.