JP2002529004A - System and method for integrating network nodes - Google Patents

Abstract

SUMMARY A system and method for locating and aligning nodes in a network includes a position determining device configured to determine a position of the node, and determining an orientation of the node within the network. Digital compass. The position and pointing information obtained from these devices can be used to calculate the pointing angle of one or more transceivers at the network node to establish a communication link. The digital compass may also provide roll and pitch information to facilitate leveling of the node or to allow a pointing system within the node to correct for leveling errors. Additional communication channels can also be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

RELATED APPLICATIONS [0001] This application is related to co-pending U.S. Patent Application Serial No. 236 /
059, the name "wireless communication network", and the reference number 237/287, whose number is to be designated, and the name "system and method for improving pointing accuracy", all of which are of a common assignee. And at the same time as the present application. This application claims the name "High Bandwidth Communication System for Large Buildings".
U.S. Patent Application Serial No. 09 / 035,373, filed March 5, 98, and "
No. 09 / 035,370, filed March 5, 1998, entitled "Combined Picocell Communication System", both of which are hereby incorporated by reference in their entirety. .

BACKGROUND OF THE INVENTION [0002] The present invention relates generally to communication systems, and more particularly to systems and methods for integrating at least one of the communication nodes in a communication network.

BACKGROUND OF THE INVENTION Over the past few years, Regional Bell Operating Co.
mpanies (RBOCs), cable carriers, and Competiti
Significant progress has been made in the deployment of fiber optic facilities by telecommunications carriers, such as ve Local Exchange Carriers (CLECs). O
With the introduction of technologies such as C-192 and DWDM, the deployment of these facilities has greatly reduced the marginal cost of bandwidth on fiber.

Thus, as a result of this development, there is a wide range of bandwidths and communication capacities in the backbone network of telecommunications carriers. However, many homes and offices do not have a practical solution to interface with these backbone networks. As a result, the direct connection of potential customers to these backbone networks is still very costly.

Currently, there are two practical ways to connect customers directly to a backbone network, such as a fiber optic network. These methods are either buried or fictitious (
Elevated) fiber interconnects and microwave connections. However, both of these methods require significant up-front costs before they can be profitable.
In the case of buried or fictitious fibers, these costs relate to obtaining the right of passage for cabling and installing the cable by burying or hanging. In the case of microwave systems, these upfront costs arise not only from the costs associated with the microwave repeater, but also from the costs associated with acquiring rights in the appropriate portion of the microwave range. Therefore, system developers and integrators have long sought to find a suitable solution to this "last mile" problem.

SUMMARY OF THE INVENTION The present invention is directed to a system and method for implementing a communication function that allows one or more users (users) to communicate with a communication network at one or more user facilities. For example, in one embodiment, the present invention allows these users to communicate with one or more backbone networks supported by a common carrier or service provider. In accordance with one aspect of the present invention, there is provided a multi-node communication network that interfaces between a plurality of buildings, houses, complex buildings or other facilities and a service provider's backbone network. According to one embodiment,
Since the nodes of the network can be provided with optical transceivers, the network links can be implemented as optical communication links. To that end, several buildings that are integrated by the network can be included in the network without having to lay cables or physically connect the facilities. In addition, the use of optical transceivers allows for wireless RF such as bandwidth, interference, FCC approvals and restrictions.
It avoids the need to consider restrictions and other issues typically associated with RF communications.

[0007] According to another aspect of the invention, a node of the network includes a transceiver pointing to another node in the network.
A transceiver may be included that is secured to a movable mount to facilitate ting. For example, in one embodiment, an azimuth and elevation mount is provided that allows the transceiver to point with some accuracy to other transceivers in the network.

[0008] In addition, one or more controllers (controllers, controllers) include each node that controls the pointing of the transceiver and provides other control mechanisms or functions useful for integrating the nodes in the network. Can be provided. In addition, the controller can perform routing of data from nodes in the network to other nodes, and interface with the backbone network in the network or interface between the network and users in the facility. Changes in the communication format that need to be taken can also be implemented.

According to another aspect of the invention, an installation fixture can be provided to facilitate installation and alignment of one or more nodes in the network. Such an installation fixture is particularly useful in embodiments where pointing and alignment are of some importance. For example, if the communication links of the network are optical links, such links tend to use relatively narrow beam widths and low power laser transmitters. Therefore, for these devices, pointing in alignment is important so that it falls within the allocated link margins.

According to one aspect of the present invention, the installation fixture includes an automatic device that determines a node position and a node orientation (eg, in which direction a point on the fixture is pointed). Can be. For example, in one embodiment, the installation fixture includes a GPS receiver for location information and a digital compass for determining node orientation.
In addition, the digital compass can also be used to determine device roll (roll, roll), pitch (pitch, pitch) and yaw (yaw, yaw) for a fixed orientation. Thus, the roll and pitch parameters can also determine the indication of the level of the installation fixture. When the installation fixture is attached to the node, once the parameters for the fixture are determined, the parameters for the node are also determined. Thus, when the installation fixture is attached to a node, the location of the node in the network,
The orientation and level can be determined.

[0011] These parameters relating to the location and orientation of the node in the network can be used to calculate the pointing angle to allow the node to communicate with other nodes in the network. In one embodiment, the installation fixture may simply be a data collection device that collects node parameters such as position and orientation information. In this embodiment, the data collection device provides these parameters to other processors to determine the appropriate pointing angle so that transceivers in the nodes can accurately point to other nodes in the network. This calculation is made, for example, by a processor in the node or by a processor or processor-based system at the central office. Alternatively, processing can be provided in the installation fixture so that the installation fixture can determine the pointing angle required to interface between the target node and other nodes in the network. it can. In addition, processing responsibilities can be shared among the various processors in the system.

In one embodiment, three-dimensional location information is known for each node in the network. Thus, relatively simple geometric calculations can be used to determine the pointing angles required to interface between the target node and other nodes in the network. This position information can be represented by x, y, z coordinates with respect to the earth. For example, the position information can be represented by latitude, longitude, and altitude (altitude). Alternate location coordinates can be used for the earth or for other fixed locations. Preferably, each node in the network utilizes the same coordinate reference so that the pointing angle can be determined without having to perform additional coordinate transformation calculations.

According to another aspect of the present invention, fine tuning of transceiver pointing can be performed. In one embodiment, a spatial detector receives a portion of the received data signal. The position where the beam hits the spatial detector indicates the pointing accuracy. This information is used to adjust the pointing of the transmitter so that, for example, the beam can be focused on a spatial detector. To avoid false detection of noise sources in one embodiment, the transmitted data signal is encoded so that it can be identified. In one example, the transmitted data signal is modulated onto a relatively low frequency carrier. The detector performs the pointing analysis based only on the low frequency signal. Other signals are ignored. Because most noise sources appear as DC signals, this approach allows the spatial detector to effectively discriminate between various signals and select the appropriate signal.

According to another aspect of the present invention, there is provided a technique for controlling an active power of a beam that carries a data signal. It is possible that the received beam is outside the dynamic range of the receiver, because the range of the atmosphere and other conditions can give a large range to the received power (power). For example, if the transmitter is tuned to deliver an appropriate output (output power) in fog or other bad weather conditions, the output will be excessive in ideal weather conditions, which may result in detector saturation. May occur.

Thus, in one embodiment, the signal strength of the received signal is measured to determine whether its power needs to be adjusted. If it needs to be adjusted, the transmitter is instructed to adjust its pointing so that the effective output (power) on the remote detector is adjusted. For example, if the power exceeds a predetermined threshold level, the transmitter can be instructed to move away from on-center pointing to reduce the signal level of the beam striking the remote detector. To that end, the effective power is reduced to an output that is within the dynamic range of the receiver. In some embodiments, this indication may be provided via a control channel on the link.

[0016] Other features and advantages of the present invention, as well as the structure and operation of various embodiments of the present invention, are described in detail below with reference to the accompanying drawings.

The present invention will be described with reference to the accompanying drawings. Like reference numerals in the drawings,
The same or functionally similar components (components) are shown. Additionally, the left-most digit (s) of a reference number identifies the drawing in which the reference number first appears.

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to systems and methods that provide improved features for communication networks. Specifically, according to one aspect of the present invention, a novel communication network is provided. The communication network is implemented to provide high quality, high bandwidth communication services to homes, offices or other facilities. Advantageously, the communication network is implemented to provide an interface between many diverse communication devices in various homes, offices or other facilities and a copper or fiber backbone carrier network.

FIG. 1 is a diagram illustrating an example communication network 100 according to an embodiment of the present invention. Referring now to FIG. 1, the example communication network 100 shown in FIG.
A plurality of nodes 108 interconnected by a communication link 110 may be provided. According to one embodiment of the present invention, network node 108
Arranged above. In the example shown in FIG. 1, only one node is provided for each facility, but one or one depending on the communication requirements and possibly a particular facility.
More than one facility 104 can have multiple nodes 108.

In one embodiment, facility 104 may be a building, tower, or other structure, land, or place. Advantageously, the facility 104 may be, for example, a house (house) or office, and preferably interfaces with one or more backbone networks of one or more common carriers or service providers. In this embodiment, network 100 may provide an interface between the facility and the backbone network.

Preferably, according to an embodiment, the node 108 comprises the optical communication link 11
0 interconnects each other. In this optical embodiment, node 108 is
It includes one or more optical transmitters and receivers and includes a communication link 110 between the plurality of nodes. Node 108 may also be implemented such that communication link 110 is an RF communication link. Although the nodes 108 may be hard wired to each other, the communication link 110 is preferably a wireless communication link to further facilitate interconnection of various facilities.

The number of transmitters and receivers provided at a node 108 can vary depending on the fan-out capacity desired at that node 108. However, in one embodiment, each node 108 has four transmitters,
The associated facility 104 can be connected to up to four other nodes 108 at four other facilities 104. Providing both a receiver and a transmitter (ie, a transceiver) for each fanout of node 108 allows two-way communication between nodes 108.

In an optical embodiment, the transceiver at node 108 may be, for example, a laser or light emitting diode (LED) as an optical transmitter, and a charge coupled device (CCD), a photomultiplier tube (PMT), a photodiode detector as a receiver. Container (P
DD) or other optical detectors. The transmitter and receiver techniques for one or more preferred optical embodiments are described in detail below.

Although the network 100 shown in FIG. 1 is shown as a forked network structure, other network structures or geometries can be implemented.

According to one aspect of the invention, network 100 includes one or more facilities 104.
Can be implemented and utilized to connect directly to the high capacity communication network 116. For example, network 100 can be used to connect multiple customers to a copper or fiber optic backbone network. Thus, advantageously, the network allows a customer to access a high-bandwidth communication network at a high data rate from the customer's home, office, or other facility, regardless of the existing connection capabilities within the facility. Thus, the network 100 can be implemented to avoid the need to cable the backbone network to the respective facility 104 beyond the "last mile".

To this end, at least one of nodes 108 is elected as root node 108A. The root node 108A has another function of interfacing between the communication network 100 and the carrier network 116 via another communication link 112. In one embodiment, carrier network 11
6 may be, for example, a high bandwidth copper or fiber service provider or general carrier network 116.

FIG. 2 is an operational flow diagram illustrating the process by which a communication network operates according to an embodiment of the present invention. In step 204, the root node 108A of the communication network 100 receives the communication from the carrier network 116. In step 208, root node 108A accepts the communication and, if necessary or desirable, communicates the communication with node 108 on communication link 1
Reformat to a format that can be transported through ten networks. For example, in an embodiment where network 110 is a packet switched network,
Root node 108A formats the communication into packets suitable for transmission over optical communication link 110.

The root node 108 A stores the data in the land (site, ptremise node)
e) Routing information can also be determined so that it can be sent to the appropriate destination node 108, also called node 108. In embodiments that use packet data, the routing information may be included in a packet header of a packet being transmitted over network 100. In another network geometry, the designation of the destination node 108 can be used instead of or in addition to routing information. For example, a ring-shaped geometric arrangement uses destination information as a packet address instead of routing information.

At step 212, root node 108 A routes the reformatted data through network 100 to the designated destination node 108. The path may be direct to destination node 108 or through one or more intermediate nodes 108, which are referred to in this role as junction nodes 108. In embodiments using packet data, for example, junction node 108 may use the packet header to route the received packet to the next node 108.

In step 216, the destination node 108 receives the data. The received data is sent to an end user at the destination node 108 facility. This is indicated by step 224. In a preferred embodiment, the data is reformatted before sending the data to the end user. In some embodiments, the data is reformatted into a telecommunications format, such as the original format in which the data was received from the carrier network 116. This is indicated by step 220.

In this embodiment, the fact that the user has been interfaced with the carrier network 116 via the network of links 110 and nodes 108 is preferably transparent to the user. . Communication from the user to the carrier network 116 occurs in a similar manner, but in reverse order. Thus, network 100 may provide a two-way connection with a carrier network 116 between one or more users in one or more facilities 104. FIG.
, Only one carrier network 116 is shown, but in other embodiments, one or more root nodes 108A may be used to interface with multiple carrier networks 116.

Thus, according to one aspect of the present invention, a service provider can provide services to users at multiple facilities 104 by providing a signal to the root node 108 A of the system. In one embodiment, node 108 uses Asynchronous Transfer Mode (ATM) as the data transport mechanism. Although node 108 may use other transport mechanisms, in this embodiment it is preferred that the service provider send the data as ATM cells to root node 108A. In this way, node 108A does not need to perform format conversion. In another embodiment, format conversion may be provided for flexibility.

To provide the ATM cells, the service provider can send a pre-concatenated signal, such as a SONET signal, to the root node 108 A via the carrier network 116.
FIG. 3 is a block diagram illustrating an embodiment where a service provider utilizes a SONET ring to interface with root node 108A. FIG. 4 is an operational flow diagram illustrating a method for utilizing the architecture shown in FIG. 3 to provide communication to an end user in accordance with one embodiment of the present invention.

Referring now to FIGS. 3 and 4, in an embodiment, an ATM switch 304 is provided at the service provider facility. At step 404, the ATM switch 30
4 is, for example, T1 line 302, Ethernet network 316 (registered trademark)
Bundle communications from various sources, such as The ATM switch 304 bundles (bundles) communications from these input sources into ATM cells. At step 406, the ATM cells can be inserted into the payload of the concatenated signal, for example, a SONET signal.

In step 408, the SONET signal is sent to an add / drop multiplexer (ADM) 322 for insertion into a high speed SONET ring. In one embodiment, the ATM switch 304 converts the received data into, for example, an OC-
Format to 3c format. Thus, in this embodiment, ATM traffic can be framed in the OC-3c format prior to transmission to the ADM 322 for input to the SONET ring 324. In some embodiments, S
The ONET ring 324 can be implemented as a high speed ring, for example, OC-192.

In step 410, the ADM 322 closest to the root node 108A
Drop the OC3-C signal onto the root node 108A. In one embodiment, the root node 108A can accept up to four OC3-C signals from the ADM 322. However, this quantity is scalable. Root node 108A is AT
Extracting the M cells, the ATM cells are routed over the communication network 100 via one or more junction nodes 108B to the designated destination node 108C. This is indicated by step 412.

At destination node 108 C, the ATM packet is reassembled into the telecommunications format expected by the end user, as shown in step 414. In one embodiment, the communication is transmitted to the identification device 312,
Reassemble the packet into a standard telecommunications format. For example, in one embodiment, the NTU 312 may be provided to reassemble the packet into a format such as SONET, STM or ATM. The formatted telecommunications signal may be provided to a user's network 318 or other communication link 322.

FIG. 5 is a diagram illustrating an example software protocol architecture for performing ATM / SONET, such as that shown in FIG. Referring now to FIG.
In the ATM switch 304, for example, Ethernet (registered trademark), T1, IP
, PRI, and AT are inserted into the OC-3c SONET signal.
Bundled with M cells. If the SONET network is a high-speed network such as, for example, OC-192, the ADM 322
It provides a transition from C-3 to OC-192 and at the exit back to OC-3c.

In the embodiment shown in FIG. 5, the root node 108 A has up to four OC-
3cSONET signal can be received. The root node 108A extracts ATM cells from the SONET signal and routes the ATM cells over one or more links 110 to a destination node. In one embodiment, communication link 110 is an optical link operating at 622 Mbps and can be switched to and disconnected from node 108 using a packet switch located at each node. Node 1
An example architecture for 08 is described in detail below. At the destination node 108C, the ATM cells are reinserted into the SONET signal, and the NTU 312 reassembles the packets into the telecommunications format desired by the user.

In the example shown in FIG. 5, the root node 108 A can receive four signals simultaneously. This quantity matches the fan-out capacity of the four communication links 110 from the root node 108A. That is, with four fan-out capacities, root node 108A can transmit data to four other nodes 108 simultaneously. Similarly, in one embodiment, at destination node 108C, this node can receive up to four signals from four other nodes 108 simultaneously. As noted above, these quantities are scalable.

FIG. 6 is a diagram illustrating functions provided in the root node 108 A according to an embodiment of the present invention. Specifically, the diagram of FIG. 6 illustrates a specific example of interfacing between the root node 108A and the network 116. In the specific example described above, the root node 108A
An OC-3c communication link 616 is provided. The headend 608 at the root node 108A extracts ATM packets from the OC-3c signal and sends them to one or more transceivers 602. The transmitter portion of transceiver 602 has
The TM packet is transmitted over one or more communication links 110 to the destination node 108C.

FIG. 7 is a diagram illustrating functions provided at destination node 108 C for interfacing between node 108 and user equipment at facility 104 in accordance with an embodiment of the present invention. Referring now to FIG. 7, the destination node 108C also
One or more transceivers 602 are provided. The receiver portion of transceiver 602 includes:
An ATM packet transmitted from the transmitter of the root node 108A is received.
This transmission is made via one or more intermediate nodes 108B. ATM packet 6
04 is transmitted to the NTU at the facility 104. NTU 624 may then provide communication in a format or formats appropriate for the user or users at facility 104, as indicated by flow line 616.

The above description made with reference to FIGS. 3 to 7 describes specific examples of communication networks that use specific protocols and data formats. After reading this description, it will be understood that many other formats, configurations and combinations are possible, and that other architectures and configurations can be implemented to accommodate such formats and protocols. It becomes clear to ordinary engineers.

The node 108 will now be described in detail according to one or more embodiments of the present invention. FIG. 8 is a diagram illustrating a specific example of a node 108 according to an embodiment of the present invention. 8 is generally cylindrical in shape, and includes four node heads 654 and one node base 656. Node head 654
Each includes a transceiver to facilitate communication with one or more other nodes 108 in the network 100. In one embodiment, each node head 654 has a single transceiver, and each node head 654 provides a communication link 110 with other nodes 108 in network 100 at some point.

Each transceiver preferably has both a receiver and a transmitter to allow two-way communication. However, in another embodiment, the node head 6
54 will have only a transmitter or only a receiver, thereby providing one-way communication. In addition, one or more node heads 654 can include multiple transceivers or additional receivers or transmitters to add capacity.
As described above, in one embodiment, the transceiver is an optical transceiver, but alternative wireless transceivers operating at wavelengths other than the optical wavelength may be implemented.

The embodiment shown in FIG. 8 includes four node heads 654. Thus,
In this embodiment where each node head has a single transceiver,
A node 108 so configured can communicate with up to four other nodes 108 at four separate locations. Other numbers of node heads 654 can be provided depending on the desired fan-out capacity for node 108. However, in one embodiment, four node heads 654, each having a two-way transceiver, are a preferred configuration.

Preferably, in one embodiment, each node head 654 is provided with a pointing mechanism so that it can rotate to face another designated node 108. In one embodiment, such pointing can be performed with azimuth (azimuth adjustment) and elevation (elevation adjustment). Ideally, each node head 654 can be directed to an individually designated node 108.

Furthermore, the specific example shown in FIG. 8 is substantially cylindrical in shape. This facilitates 360-degree full circle pointing to other nodes. One advantage of this shape is that the optical communication beam is always approximately perpendicular to the cylindrical housing, regardless of pointing. This helps to maximize the transmitted beam power (power). Note that each node head 654 also forms part of a cylinder in the vertical direction so that when the beam is directed in the elevation direction, the beam can pass orthogonally through the housing. Of course, other shapes of the housing can be realized.

It is noted that in one embodiment, one or more node heads 654 may include communication devices that can communicate with devices other than other nodes 108. The apparatus can be implemented using, for example, a wireless communication (RF communication) technique or another communication technique. However, in a preferred embodiment, node head 654 is dedicated to communication between nodes via communication link 110.

The node base 656 can include electronics and mechanisms, for example, to form a communication interface between the network 116 and one or more node heads 654. A communication interface that performs protocol and format conversions may comprise the node base 656 and a mechanism for driving the pointing of one or more node heads 654.

The details of node head 654 and node base 656 will now be described in accordance with one embodiment of the present invention. FIG. 9 is a block diagram illustrating a logical breakdown of components that can be included in an example node head 654 in accordance with one embodiment of the present invention. This logical grouping is for illustrative purposes only and is not
4 shall be interpreted as not requiring a specific physical architecture. The embodiment shown in FIG. 9 is an optical embodiment, in which node head 654 communicates with other node heads 654 in other nodes 108 via optical link 110.

Referring now to FIG. 9, an example of a node head 654 can have three logical groupings of components: optical element 670, mechanism 680, and electronics 690. In the case of a node head 654 having a transceiver, the optical elements include a transmitting optical element 674, a receiving optical element 672, and a tracking optical element 6
76 is provided. The optics can also include associated electro-optics such as, for example, laser transmitters, CCD detectors, and the like. In one embodiment, the transmitter and the detector are bored with each other during manufacturing so that bidirectional pointing accuracy is established and maintained.

The mechanism 680 includes a gimbal platform (gimbal platform).
s), and an enclosure (casing) for isolating the electronic device from the constituent members. In one embodiment, the gimbal platforms are an azimuth gimbal 682 and an elevation gimbal 684. This azimuth / elevation configuration is preferred because it allows pointing to node 108 in a wide range of orientations. In one embodiment, each node head 654 can rotate 370 ° in azimuth and ± 20 ° in elevation to point to another node 108. However, other ranges may be used.

Note that other platforms with, for example, XY optical mounts can be used. A motor or other drive mechanism can be used to drive the gimbal. In one embodiment, the motor is a belt driven stepper motor, but a direct driven motor or a geared motor could be used. Optical encoders and limit stops / switches can be provided for accurate pointing.

In one embodiment, the housing is an acrylic housing that is transparent to the wavelength of communication link 110. The housing can also function as a filter to filter out unwanted noise from wavelengths other than the communication link 110. For example, in the embodiment considered here, where the communication wavelength is 780 nanometers (nm),
The housing can provide a 780 nm bandpass filter. In one embodiment, each housing is about 4.5 inches high and about 12 inches in diameter.
However, other dimensions are possible. The external dimensions are preferably minimized to the extent possible based on the size and placement of the components of the node head 654.

For example, the electronic device 690 can include a transmitter driver 692, a receiver 694, a detection electronic device 696, and a communication electronic device 698. In one embodiment, the transmitter has an on-off keyed (OOK) at approximately 780 nanometer (nm) wavelength, at approximately 20 milliwatts (mW) average power (power).
2) A semiconductor laser diode modulated in a mode. The divergence of the beam is preferably 1.5 milliradians (mrad) and is visually safe at the aperture. Of course, other approaches can be implemented with transmitters operating at various wavelengths, powers and divergence. In fact, in RF applications the wavelength of operation is not within the optical spectral range.

The receiver can be realized using an optical detector in an optical embodiment. For example, in one embodiment, the receiver detects a PIN or an avalanche photodiode detector (A) with a 50 mm aperture to detect the total amount of transmitter power received.
PD). Avalanche photodiodes are approximately 10 dB more sensitive than PIN photodiodes, but are generally more complex to implement. Therefore, PIN detectors are preferred in applications where link margins are allowed. Other detectors are available to detect energy at optical or other wavelengths depending on the application.

The detection electronics may, in one embodiment, include a quadrant PIN detector having two views and positioned in the optical path of the receiver. Preferably the quadrant detectors (detectors with quadrants 1 to 4) are separated from the receiver by a 4% beam splitter. A 4% diffracted signal of the received signal is imaged on a quadrant detector, producing an error signal depending on the relative signal strength in each quadrant. The error signal is processed to determine a pointing offset.
The pointing offset is used to generate an error signal (error signal) to drive the azimuth and elevation gimbal 682, 684 to correct for pointing errors. In one embodiment, a processor is used to maintain the tracking loop. The processor is the node head 564
Other control and communication functions can be provided.

In one embodiment, the photodetector is positioned at the focal point of a 50 mm diameter doublet lens with an 80 mm focal length. A band filter having a 20 nm (nanometer) bandwidth centered at 780 nm with a diameter of 20 mm,
It is placed just before the receiving photodiode with a diameter of 600 microns. The light collected by the receiving lens is imaged on a spot on the receiving photodiode.

Communication electronics 698 is used to interface between node head 654 and node base 656. In some embodiments, a bus connects a plurality of node heads 654 to a node base 656. In this embodiment, the multiplexers can be communicated between various components over a shared bus.
It can be provided as a part of the communication electronic device 698.

Each of these components will now be described in detail according to an embodiment of the present invention. As mentioned above, the transceiver (optical in some embodiments)
Mounted on gimbal to facilitate pointing. In one embodiment, the transceiver is mounted on an elevation gimbal, and then the gimbal is mounted on an azimuth platform. The elevation gimbal provides, in one embodiment, a range of movement of ± 20 degrees, and the azimuth platform can rotate a total of 370 degrees about an axis. Thus, the node head 654
If another node 108 is provided within the line of sight and within ± 20 degrees of the elevation, the two nodes 108 can be communicably connected.

In one embodiment, the gimbal axis is operated by a belt driven stepper motor. The stepper motor can be controlled by clock and direction signals provided by a processor in node base 656, for example. The stepper motor causes the platform to rotate in azimuth and elevation in discrete steps. Preferably, the platform can be driven to a resolution approximately ten times finer than the dispersion of the transmitting laser. Thus, in one embodiment where the degree of dispersion of the transmitted laser beam is 1.5 mrads, the gimbal resolution is about 1
50 microradians (μrads).

Preferably, in one embodiment, the stepper motor drives a toothed timing belt connected to the azimuth and elevation gimbals via a toothed pulley. Other drive mechanisms can be used, but the toothed belt mechanism is more accurate and less costly. The toothed belt mechanism provides a means to minimize belt slippage. The motor has about 1.57 mrad per step resolution and an appropriate turndown ratio. In one embodiment, the azimuth down ratio is 9.28: 1 and the elevation ratio is 12: 1. This is 16
Provides a spatial resolution of 130 rads for 9 rads and elevation. In some embodiments, each motor has an internal gear train to reduce movement of the motor armature. For example, in one embodiment, the gearing is 1000: 1.
To provide a reduction ratio. This allows the motor to maintain its position even when its drive coil is not excited.

In one embodiment, the gimbal is rotated (indexed) to an absolute reference point to provide a reference for pointing determination. This reference point may be provided by a limit switch located in the extreme range of movement of either axis. Thus, at the time of set-up or other calibration, the gimbal is commanded to move to its limit position and sends a signal to the microprocessor indicating its absolute position. The microprocessor can use signals from the gimbal position encoder to maintain position information and drive the gimbal to the required position.

As described above, in the optical embodiment described above, the housing of the node head 654 is an acrylic cylindrical body that is transparent to 780 nm communication signal wavelengths. In some embodiments, the acrylic may be dark red to provide thermal protection for the internal components. The caps on the top and bottom of the enclosure can be manufactured, for example, from machined aluminum. The caps are provided with seals to keep out moisture or other undesirable components. In one embodiment, the seal is an O-ring groove into which the top and bottom edges of the acrylic cylinder fit. Rubber, rubbery or polymeric O-rings can be provided in the grooves to form a good seal. In a preferred embodiment, a single acrylic cylinder surrounds each of the node heads 654 in the node stack. This stack can be purged with dry nitrogen and sealed with a sealant. Preferably, there is sufficient space above the upper node head 654 to allow sufficient air circulation. Although not strictly necessary, thermoelectric or other types of temperature control equipment can be provided to maintain the required equilibrium temperature. In some embodiments, equilibrium approximately 12 degrees above ambient temperature is preferred.

FIG. 10 is a block diagram illustrating an embodiment of a communication receiver circuit 694 according to an embodiment of the present invention. The purpose of the receiver 694 is to receive a signal from another node 108 of the network 100. Preferably, data being transferred from another node 108 is modulated onto the received signal. Receiver 694 is
Process the received modulated signal so that it can be repeated or forwarded to another node in network 100. Alternatively, the processed signal may be sent to either the end user at facility 104 or to network 116.

The example receiver shown in FIG. 10 is an optical receiver configured to receive an on-off key (OOK) data modulated optical signal. The receiver is further configured to convert the signal to a voltage level, amplify the data by a phase locked oscillator (of a phase locked loop) clock recovery, and retime. The operation of the receiver circuit of this example will now be described. After reading this description, it will be apparent to one of ordinary skill in the art that receiver 694 can receive signals modulated by other receiver detectors, architectures, or configurations, or at wavelengths other than optical wavelengths. It will be clear how this will be achieved.

In the embodiment shown in FIG. 10, light from the communication of link 110 is focused onto optical detector 704. In one embodiment, optical detector 704 is a high-speed optical detector, such as, for example, a PIN photodiode detector or an avalanche photodiode. As mentioned above, in embodiments, PIN photodiode detectors are preferred over avalanche photodiode detectors. However, shown in FIG. 10 are components that may also be included for embodiments that use avalanche photodiode detectors. These additional components are shaded with oblique parallel lines in FIG. These additional components provide control and temperature compensation of the high voltage bias supplied to the avalanche photodiode.

An embodiment of the PIN photodiode detector is described first. For a PIN photodiode detector, a bias voltage can be applied to the cathode of the photodiode detector 704 through a series resistor 706. In one embodiment, the bias voltage is 12 volts, although other bias voltages can be selected. Resistance 7
The voltage drop at 06 is preferably proportional to the DC component of light illuminance (intensity) (including background light) and is detected and amplified by an amplifier such as, for example, differential amplifier 708. The output of the differential amplifier 708 provides a signal indicative of the received output.

Light from the data signal is focused on the active area of photodetector 704. Photodetector 7
04 generates a photocurrent proportional to the illuminance of light impinging on the active area of the photodetector 704. The amplifier 710 converts the generated photocurrent into a voltage signal. In one embodiment, amplifier 710 is implemented as a high speed transimpedance amplifier that converts the photocurrent to a differential voltage signal. An example of a high speed transimpedance amplifier is the Maxim MAX3664 transimpedance amplifier available from Maxim Integrated Products, Inc. of Sunnyvale, CA.

The voltage signal can then be filtered by a low pass filter 712 to reduce high frequency noise before further amplification. In some embodiments, the low-pass filter 712 may be a third type 500, although other filters or bandpass frequencies may be used.
MHz low-pass filter.

Data retiming and limiting amplifier 714 provides additional amplification of the signal, re-time the data to the clock within the phase locked oscillator (phase locked loop), and direct the signal to output connector 740. Can be included to send.
In one embodiment, the retiming and limiting amplifier 714 provides 622 signals per second.
Implemented using a Maxim MAX3675 device that provides an AC-coupled differential ECL output that is re-timed to the phase-locked oscillator clock at a nominal data rate of Mbit. Other amplifiers are feasible, include alternative output levels, and can operate at alternative clock and data rates.

As noted, the output of amplifier 714 is sent to output connector 716, which in one embodiment is an SMA type connector for connecting a high data rate switch at node base 656. The limiting and re-timer amplifier 714 includes a received signal strength indicator (RSSI), loss of lock signal, and diagnostic purposes and L
Provides a loss of power signal provided for ED indication. As described below, R
The SSI can be used to determine if the received signal is within the dynamic range of the receiver, or if the effective transmit power (transmit power) needs to be adjusted. If needed, a voltage regulator 716 can be included to regulate the supply voltage provided to the amplifier 714.

In one embodiment, a temperature sensor 718 is also provided to generate a current signal indicative of the temperature of the photodetector circuit. This is useful if the operation of the receiver is very temperature dependent. In one embodiment, the temperature sensor 718
Provides a signal of 10 millivolts per kelvin (mv / kelvin) through differential amplifier 722. This signal can be used for diagnostic purposes. In the embodiment shown in FIG. 10, a differential amplifier 722 senses the voltage dropped across the series resistor 720.

Various signals can be connected to the receiver 694 via the connector 740. The diagnostic signal may be provided from receiver 694 to a processor or other device. These diagnostic signals may include, for example, signals such as temperature, received signal strength, and DC (direct current) received optical output. The connector 740 is connected to the communication receiver 6
It can also be used to supply the voltage levels used for operation of the components in 94. Alternative connectors may be used, but to reduce parts and assembly costs, in one embodiment, connector 740 is an insulated displacement connector (ID
10) 100 mil double row header compatible with C) and ribbon cables.

As mentioned above, if the photodiode detector 704 is an avalanche photodiode, it can include components shown shaded with oblique parallel lines. The high voltage bias of the avalanche photodiode detector 704 is provided by a high voltage voltage divider 732 which is controlled by a sense resistor voltage divider 734 and an operational amplifier integrator 736. In one embodiment, the applied voltage can be adjusted manually using a control potentiometer 738 or the potentiometer 738
And the high voltage control line can be set externally by setting it to a voltage proportional to the desired final voltage at the avalanche photodiode 704.

FIG. 11 is a block diagram illustrating an example of a transmitting circuit according to one embodiment of the present invention. In particular, the embodiment shown in FIG. 11 is an embodiment of a laser transmitter configured to transmit an optical signal to another node 108 over a communication link 110. After reading this description, it will become apparent to a person of ordinary skill in the art how to implement an alternative embodiment transmitter, including alternative transmitters, architectures or configurations.

In the embodiment shown in FIG. 11, transmitted data is received at data input connector 742 and provided to laser driver 744. As described above, in one embodiment, the data is modulated at 622 Mbits per second. Therefore, in this embodiment, laser driver 744 is preferably a high speed laser driver. More specifically, in one embodiment, the laser driver 7
Numeral 44 is a current driver designed for operation at 622 Mbits per second, which is connected to the MAX3 MAX3 directly connected to the cathode of the communication laser diode 746.
It is implemented as a 766 laser driver.

In some embodiments, the communication laser diode 746 may provide signal degradation and EMI
It is mounted directly on the circuit board in proximity to the driver 744 to minimize emissions. The anode of laser diode 746 is connected to Vcc.
In some embodiments, MAX3766 controlled by a node-based processor
There is a laser enable function above. The optical power sensor is a laser diode 746.
Is used in a feedback loop having a laser power control circuit 750 to control the average output power of the Laser output control circuit 750 also provides a diagnostic laser output signal via connector 740.

In the embodiment shown in FIG. 11, a temperature control circuit is also provided. It is desirable to provide a temperature controller because laser diodes tend to have a very short life when their operating temperature is above about 40 degrees Celsius. Thus, in this embodiment, a temperature sensor 752 is provided. In one embodiment, temperature sensor 752 is an integrated circuit that converts temperature to current, and is preferably mounted in close proximity to laser diode 746. In this embodiment, a voltage drop across a resistor 754 in series with a temperature sensor 752 is detected by a differential amplifier 756. Differential amplifier 756 provides a temperature diagnostic signal to the control processor via connector 740. If the processor determines that the operating temperature is too high, it can take corrective action. As an example, such a corrective action may include deactivating laser driver 744.

A part of the temperature control circuit shown in FIG. 11 is a temperature control device 758 that senses a voltage drop at the series resistor 754. The temperature controller 758 can be used to drive a cooler 760 that attempts to cool the laser diode 746. Although other coolers can be used, in some embodiments cooler 76
0 is the wide copper top trace (also in contact with the laser diode package)
Implemented as a thermoelectric Peltier junction cooler that is attached directly to an average copper top trace. In this way, the Peltier junction provides heat conduction cooling to laser diode 746.

As mentioned above, in one embodiment, the transmitter is a single mode laser diode operating at 780 nm with an output aperture of about 3 microns by 5 microns. The output aperture may be located at the focal point of a lens of a 50 mm diameter double lens with a focal length of 120 mm. Some embodiments include a holographic diffuser and can be located between these two elements. In some embodiments, the diffuser has a nominal intrinsic divergence of 1 °. Positioning the diffuser at about one-tenth of the distance between the laser diode and the objective produces a divergent output beam of 1.5 mrad. In some embodiments, the focal length of the lens is such that the average output from the transmit aperture is the AN
SI Z. It is chosen to be less than 1.5 mW / cm ² meeting the 136 standard. In one embodiment, the beam profile is for astigmatism exiting the laser and has a full width at half maximum (FWM) of about 23 ° in the horizontal direction and 9 ° in the vertical direction.

FIG. 12 is a diagram illustrating an example of a beacon laser according to one embodiment of the present invention. The beacon laser can be implemented with a wider beam, thereby reducing acquisition time, for example, if there is a large degree of uncertainty in the location information. In the embodiment shown in FIG. 12, the beacon laser
Among them are a pulse timer 764, a high speed driver 766, a high current FET 768, and a beacon laser 770. The beacon laser may also include a regulated potentiometer 722 and a voltage regulator 774. During operation, the stability timer 762 provides a clock signal. In one embodiment, the clock signal is provided at 660 Hz. The rising edge of this clock signal triggers pulse timer 764, which in one embodiment is a double monostable pulse timer that produces a 1 microsecond pulse. This microsecond pulse drives a high speed driver 766, whose output is high speed,
Connected to the gate of a high current and channel FET (field effect transistor).
FET 768 drives beacon laser 770 to provide one microsecond (second) output pulse.

In one embodiment, the output is 20 watts peak power. Preferably, beacon laser 770 is mounted close to FET 768 to minimize signal degradation and EMI emissions. The beacon laser 770 can also be mounted directly on the circuit board, and the heat sink can be mounted on copper traces that contact the cold surface of the thermoelectric cooler 760. The voltage regulator 774 is
It provides a bias voltage to driver 766 and FET 768. This can be adjusted manually by including a potentiometer 772.

[0085] Also included in one embodiment, as part of the communications package, is a multiplexer board. Where signals between the node head 654 and the node base 656 are communicated along one or more shared signal paths, a multiplexer board may be used. The primary purpose of the multiplexer board is to connect the communication receiver circuit, detection circuit, transmission circuit, azimuth and elevation circuit to the node base 656. Preferably, in one embodiment,
Each node head 654 includes a multiplexer board located inside the node head enclosure. Thus, in this embodiment,
A multiplexer board is required for each of the node heads 654 in the node 108.

Preferably, a number of tracking, diagnostic and control signals are transmitted to the node head 6.
A multiplex scheme is provided as this interface to minimize the number of electrical conductors that would be required to transmit between the 54 and the node base 656. In one embodiment, a multiplexer, an address line, and a single coaxial input / output line are utilized. An address line is bussed to each of the node heads 654, but one or more of the node heads 10
8 may have a dedicated coaxial single line. This is the wire count (wi
re-count) to a minimum number. In addition to communication media other than coaxial cable, other multiplex configurations can be used. Coaxial cable is preferably used for its ability to transmit high bandwidth data with minimal noise.

In a preferred embodiment, the multiplexer is an 8-channel analog multiplexer used to relay tracking error signals, diagnostic signals, and limit switch signals from one or more node heads 654 to node base 656. In addition, an 8-channel digital multiplex latch can be used to receive various digital command signals from the node base 656 via the signal interface. After reading this description, it will become apparent to one of ordinary skill in the art how other circuits, devices, and techniques can be used to provide communication between node head 654 and node base 656. It will be.
For example, the signal for node head 654 need not be multiplexed on a shared channel. Instead, a direct signal path is provided for the signal between the node head 654 and the node base 656. The multiplexer board can also be used to provide power and ground signals to node head 654.

The one or more node bases 656, among other functions,
8 and provide node 108 to facility 104 or network 1
16 can be included within node 108 to connect to the same. Alternatively, these functions can be represented among one or more node heads 654.
FIG. 13 is a block diagram illustrating a logical breakdown of components of an exemplary node base 656, in accordance with one embodiment of the present invention. This logical classification is provided for illustrative purposes only and should not be construed as requiring a particular physical architecture of the node base 656. Here, referring to FIG.
6 includes a mechanical component 804 and an electronic circuit or electrical component 810. The mechanical aspects of the node base 656 include a mount 806 for attaching the node base 656 to the facility 104 and structures utilized to connect the power supply 808 to the node base 656. The electronic circuit 810, in the illustrated example,
Processor 812, packet switch 814, auxiliary channel 816, power 818
, A temperature control 820, and a transfer interface 822. Each of these logical components is described herein.

The base mount 806 provides a physical mount that allows the node 108 to be mounted on the premises of the facility 104. Preferably, in certain embodiments, base mount 806 provides at least two functions. One function that the base mount 806 can perform is a leveling (leveling) function or otherwise adjust the position or orientation of the node 108. To this end, in some embodiments, the base mount 806 may include a leveling device, such as, for example, a mechanical ball joint device, or other device that allows leveling of the device.

Further, node 108 may include a two-dimensional level indicator so that node 108 can level to a certain degree of accuracy. In some embodiments, the base mount 806 allows for leveling to approximately one-half to one-third of an degree on each axis, although other levels of accuracy may be provided. In some embodiments, proper leveling of nodes 108 allows for more accurate pointing, as described below.

A second function of base mount 806 is to provide a path for transferring heat from node 108. In this manner, base mount 806 may include thermal fins or other devices to help convectively cool node base 656.

The mechanical interface 808 includes power and signal lines and the facility 104.
To provide an interface for the cable from to the node 108. Preferably, the mechanical interface provides some protection from the components and limits moisture or other unwanted components from gaining access to node 108.

An electronic circuit component 810 according to one embodiment is now described. In some embodiments, auxiliary channel 816 may be included to provide communication between node 108 and another entity separate from or in addition to communication link 110 and network 116. Can be. Such an auxiliary channel 816 may be provided for at least one of two or more purposes. One purpose may be to pass data to or from a new node 108 during installation. Thus, before the node is connected to the facility 104 or the network 116, the auxiliary channel 816 allows the node 108 to communicate with other entities to facilitate installation or otherwise share data for other purposes. Can be used for

In addition, the auxiliary channel 816 provides a field lifetime (fie
It can be used to provide an auxiliary channel for node 108 for communication during ldlife). For example, the auxiliary channel 816 can be used to provide status or other signals to another entity, or to receive control signals or updates from another entity. In one example implementation, the other entities mentioned in this description are, for example, a central office or other office through which network 100 can be controlled, monitored, or coordinated. Auxiliary channel 816 may be used during installation and integration with node 108 and network 100, or during operation of node 108 within network 100. The functions and communications that can be provided in connection with the installation and integration processes are described in further detail below in the section describing the installation fixture.

In one embodiment, auxiliary channel 816 may use a two-way paging protocol, such as, for example, ReFlex 25 or 50, for passing data between node 108 and the central office or other network management application. Other protocols or formats could be used, but ReFl
ex25 or 50 is Motorola's proprietary protocol. The two-way pager may be connected to the node-based 655 main processor using, for example, an RS-232 data link. In alternative embodiments, other communication formats or protocols can be used to provide the auxiliary channel 816. Preferably, the auxiliary channel is a radio R so that no line of site communication is required.
Provided as F communication link.

The auxiliary channel 816 may be used to communicate with the node 108 if the node 108 has “disappeared” from the network. In this way,
If other transport channels of node 108 (ie, channel 110) are not functioning, auxiliary channel 816 can be used. For example, the auxiliary channel 816 can be used to send communications to and receive communications from nodes 108 that are otherwise disabled. In this application, auxiliary channel 8
16 can send status information to the central office, which may give the technician an indication of any problems that may exist at node 108. Thus, if a technician is dispatched to the facility 104 to repair a disabled node 108, the technician will gain this information before leaving the station and be better prepared. In one embodiment, the auxiliary channel 816 is battery powered or capable of operating in the event of a power outage somewhere else in the node 108,
Power is supplied by solar heat.

FIG. 14 is a diagram illustrating an example implementation of the auxiliary channel 816 according to an embodiment of the present invention using the ReFlex 25 or 50 protocol. After reading this description, it will become apparent to a person of ordinary skill in the art how to implement the auxiliary channel 816 using other formats or protocols. Data from node 108 originating within processor 840 is transmitted to a ReFlex-based remote pager 842, preferably via an RS-232 interface. ReFlex
The remote pager 842 transmits this data on the auxiliary channel 816, eg, ReFl
transmit to a receiver 846, such as an ex 25 NPCS receiver 846. Receiver 84
6 provides these signals to the RF director 850. According to the ReFlex format, this is performed via a satellite link between the receiver 846 and the RF director 850. However, alternative links may be provided.

The RF director 850 sends data to either the paging terminal 852 and the ReFlex transmitter 854 to provide data to the central office 858 or to the central office 858 via the Internet 860 or modem 862. The communication path operates similarly in the opposite direction. The central office 858 has a local ReFl
The communication is transmitted to the ex receiver 856. The receiver provides data over a satellite link to an RF director 850, which transmits the data to a ReFlex
Download to node 108 via transmitter 854. Modems and / or Internet communications could be provided to the nodes, but they are not provided in the illustrated embodiment. Thus, communication from central office 858 to node 108 is performed via transmitter 854. The description provided above with respect to FIG. 14 describes the ReFlex communication in detail, but other communication systems,
A protocol or format may be used to provide an interface via an auxiliary channel between node 108 and central office 858.

As mentioned above, in one embodiment, data is transported across network 100 using ATM packets. Thus, in this embodiment, packet switch 814 is an ATM switch. In an alternative embodiment, an alternative packet switch is provided. Further, in embodiments where communication between nodes 108 is not packetized, an alternative interface for communication link 110 may be provided.

Also, as described above, in one embodiment, node 108 includes the ability to connect to four separate communication links 110. Thus, in this embodiment,
Node 108 can multiplex cell streams from downstream optical links as well as from customers at the input end. A node may also multiplex one or more output cell streams for delivery to the next closest upstream node 108. Specifically, in one embodiment, nodes 108 may have up to four
One cell stream can be multiplexed. That is, three from the downstream optical link 110,
And one from the customer. Preferably, the multiple streams are multiplexed into a single stream for delivery to the next upstream node 108 via the communication link 110. Of course, due to different network configurations, these factors can be scaled accordingly. Further, additional features can be provided to prepare for expansion of the network 100.

Each node 108 may demultiplex the signal into a cell stream for communication to one or more nodes via optical link 110 and to customers within facility 104. . For example, in an example embodiment, such as the embodiment shown in FIG. 1, a 6 × 6 ATM switch is sufficient. In one embodiment, the ATM switch operates at the OC-12 data rate because the data rate is 622 Mbits per second. Other data rates can be selected according to the requirements of the application.

[0102] In one embodiment, switch 814 is configured to enable it to create a virtual path.
Be prepared to accept network management commands. In other words,
The routing tables (routing tables) of the switches 814 allow them to respond to commands issued by the software and allow them to translate the virtual routing identifier of each incoming cell into a predetermined routing. It is configured. Further, switch 814 preferably includes diagnostic features including the ability to report cell loss statistics to the central office. Such statistics may be included over the communication network 116 via the auxiliary channel 816 or otherwise in the data stream.

In general, ATM switches are well known in the art and therefore will not be described in further detail here. In general, ATM switches detect incoming cells, align the boundaries of incoming cells on multiple input lines, inspect the VPI to determine cell routing, and write the serial stream to a word. Convert to parallel format and time multiplex words into time slots on a shared bus. The routing controller may provide a routing decision conversion command to the routing table or accept an incoming virtual route identifier from the line interface and provide a correct routing command. Multiple routing elements can be provided for each output. The routing element examines the routing instructions associated with each word appearing on the shared bus and delivers only those cell segments for its output to its corresponding output queue.

In an ATM implementation, each output queue reassembles (reassembles) incoming words into ATM cells and delivers each ATM cell in serial format to a corresponding output port.

The I / O interface 820 provides the ability to connect the node base 656 to a node head 654 or other external device. In some embodiments, an access port may be provided on top of upper node head 64 to provide easy access to I / O links after node 108 is installed at facility 104.

In one embodiment, a diagnostic interface is included to provide a communication link from the node base 656 to an installation fixture or external diagnostic device. Although any number of link types can be provided, in some embodiments it is an optical link because it can maintain the integrity of the enclosure. Thus, the access port for diagnostic I / O is a window that is transparent to infrared radiation. In one embodiment, the diagnostic I / O is IrDA (Infrared Data Acquisition)
It is infrared based.

A data input / output section is also provided to allow data to be exchanged between node base 656 and node head 654. In one embodiment, where node head 654 is addressed, data I / O is transmitted to a particular node head 65.
Includes multiple address lines that allow four choices. This addressing capability is useful in embodiments where the communication between node head 654 and node base 656 is a multiplexed communication. Of course, in embodiments where addressing is not required, these address lines need not be provided.

In one embodiment, the address line comprises, for example, a digital potentiometer, a register,
Alternatively, address lines may be provided and used to allow data to be written to various components within the node head 654, such as other devices or components. Another function of data I / O 814 is to digitize signals coming from node head 654 in analog form so that their data can be interpreted by a processor in node base 656. If address lines are used, the number of lines may be determined based on the number of devices or components being addressed.

The electronics of the node base 656 may also include the controller 812. In one embodiment, controller 812 is a processor-based controller 812. In some implementations, the processor-based controller can be implemented using one or more microprocessors to provide node-based 656 control and operation. Further, controller 812 may include one or more node heads 654
Function and operation can be controlled. The microprocessor controller 812 of this example embodiment includes a memory and packet switch 814, an auxiliary channel 81
6, and an interface to the I / O 820.

One function of controller 812 is to receive communication signals from network 816 and provide these signals to one or more node heads 654 for routing on the network. is there. These functions can be performed by controller 812 regardless of the data format selected for network 116 and network 100. However, the processor will be required to perform some level of protocol conversion, as most implementations generally have different communication protocols over network 116 and network 100.

While a variety of different communication protocols may be supported, in the embodiment described above, network 116 utilizes OC3-C SONET signals from customers. A transfer board 822 is described for this embodiment.
In this embodiment, the linked SONET signal has become widespread as a customer's central office equipment having ATM cells in a SONET structure. Thus, in this embodiment,
The transfer board 822 strips the SONET overhead and removes the four 155
A megabit / second ATM stream can be overlaid on a single 622 megabit / second ATM stream. This single stream is then forwarded to packet switch 814, where one or more abnormal node heads 6
54 routes the network 100. In this embodiment, this function is implemented because the root node 108A of the network 100 has been designated to communicate with the communication network 116, so that the root node 108A
Only happens within.

Another function that can be accomplished by processor 812 is to receive communications from communication link 110 and provide these communications in a communications protocol that is acceptable to an end user within facility 104. Again, although a number of communication formats and protocols may be supported, the functionality of controller 812 will be described with reference to the embodiments described above. In this embodiment, the processor 81
2 can accept a stream of ATM cells from the switch 814 at 622 Mbit / s. This stream is demultiplexed by four 155
It is demultiplexed into a megabit / second ATM cell stream, encapsulated in SONET, then provided to the customer's NTU and delivered to the end user in the facility 104. This signal can also be scrambled and encoded or provide an error check such as, for example, a cyclic redundancy check (CRC).

In one embodiment of the present invention, a commercially available chipset can be used. For example, the OC3-C signal at the root node 108A is
ra Sonnet ATM mapping (mapping) chip, Lucent DE
The TROIT 4-way lead can be input to a chipset, such as an ATM / SONET chipset or another mapping chipset. The SONET overhead can be stripped from each signal using an overhead processor and the overhead information can be passed to the microprocessor 880. The overhead processor may also provide the processor 880 with pointer (location) sequential translation information to determine where the payload resides in the SONET signal. The payload is then passed to the packet switch 814 where it is delineated and reconstructed so that the signal is visible, opening the capsule and verifying the CRC. In one embodiment, the ATM cells exit the packet switch via the UTOPIA interface, are input to a 4-to-1 multiplexer, and are output as 622 Mbit / s ATM cells.

For the destination node 108 C, a stream of 622 Mbit / s ATM cells from one of the node heads 654 is provided to one to four multiplexers, among which four are located. Converted to a 155 Mbit / sec ATM cell bit stream. These bitstreams are then Luc
The packet is supplied to a packet / cell processor (or a commercially available chipset) of the ent DETROIT chipset, and is subjected to encapsulation, scrambling, and generation of a CRC. These bitstreams are then sent to an SPE mapper and then to an overhead processor, where they are
Appears in standard SONET format for output to the customer's NTU.

Although the particular embodiments described above are provided with specific components and communication formats, those skilled in the art will be able to handle alternative communication formats and protocols as well, 116 and network 11
It should be appreciated that a suitable diversion can be performed between zero and the end user at facility 104. Further, within the described protocols and formats, various bit rates and fan-out performances can also be accommodated.

The processor 880 can use the local memory 884 to assist in performing this function. The memory 884 may consist of conventional RAM and ROM functions associated with a processor-based system. Although microprocessor 880 is illustrated as a single processor.
The functions may be performed by one or more microprocessors operating in conjunction with one other processor.

As described above, one or more embodiments of communication network 100 may comprise a plurality of nodes 108 that provide communication links 110 that make up the communication network. As further described above, the plurality of nodes 108 may be one or more elements capable of implementing various communication links 100 across the network 100, referred to above as node heads 654. Consisting of Specifically, in certain embodiments of network 100 described above, each of nodes 108 includes one or more transceivers pointing to other nodes 108 in the network. ing.

For relatively low bandwidth signals, it is important that the transceiver at node 108 point to the transceiver at another node with some accuracy. This is particularly important for applications where the communication link 110 is implemented as an optical communication (optical) link, where the optical signal has a relatively narrow beam width and low divergence. More accurate pointing is to a certain extent node 108 in network 100.
Depends on the positional accuracy of

Accordingly, an installation fixture may be provided to facilitate the installation and integration of one or more nodes 108 within a network such as the optical communication network 100 described above. it can. This installation fixture will now be described in terms of an embodiment suitable for operation with the optical communication network 100 described above. But,
After reading this description, those skilled in the art will be able to implement installation fixtures for pointing or other applications in which position determination is desired to be achieved with a certain level of accuracy.

FIG. 15 is a block diagram illustrating an embodiment of the installation fixture according to the present invention. Referring now to FIG. 15, an embodiment of the installation fixture includes a global positioning system (GPS) receiver 9.
04, a digital compass 908, a controller 912, an operator interface 916, an auxiliary channel 920, a local storage 928, a communication interface 916 to the transceiver, and a network interface 924. Each of these components that can be included in the installation fixture is described herein.

In one embodiment, GPS receiver 904 is a GPS receiver capable of receiving GPS pointing (location) information and determining the location of an installation fixture. In one embodiment, differential GPS is used to improve the accuracy of position determination over conventional GPS receivers. In some embodiments using differential GPS, position determination can be at the meter or sub-meter level. Preferably, the GPS receiver is provided with X, Y, and Z position determination functions with respect to the ground reference so that the location of the installation fixture can be accurately determined.

In one embodiment, the service of a differential GPS receiver 904 by Fugro's Omnistar Service is provided. This service uses geostationary satellites to provide pointing information that works up to about one meter. For example, a conventional non-differential GPS or other pointing system such as a pointing service or device can be used. Node 1
08 may be manually monitored by a monitoring device for position determination, but is preferably an automated device such as a GPS receiver 904 is used. With such a device, an automated and faster positioning of the installation fixture can be performed. Once determined, pointing (position) information, typically represented in the sense of a coordinate position (ie, a position on the X, Y, and Z axes), is provided to controller 912.

In the sense of the network 100 described above, an installation fixture according to the invention can be mounted on the node 108. In this manner, the installation fixture can be used in the example network 100 to integrate (embed) the note 108 within the network. Specifically, the network 1 is installed using the installation fixture.
The location of the node 108 within the range of 00 and also the parameters of the node, such as the placement of the node, can be determined. This information can be used to facilitate pointing of various node heads 654 within node 108.

A digital compass 908 can be provided to determine the placement of the installation fixture. In one embodiment, the installation fixture is mounted on the node 108 such that the arrangement of the installation fixture is matched with the arrangement of the node 108. In this embodiment, the technician can install the installation fixture at node 108 with index marks, grooves, slots, channels, keys, bellows and groove type fixtures or other structures.
To ensure that these two components are correctly aligned with each other. With these structures, the alignment can be prevented from being deviated in the installation process.

In this way, the determination of the placement or “pointing direction” of the installation fixture provides a determination of the orientation of the node 108 attached to the installation fixture. From this information, the pointing of one or more transceivers in node 108 can be determined. In some embodiments, this determination can be made using features such as, for example, the stops, limit switches, and position encoders described above.

In one embodiment, digital compass 908 provides an orientation for magnetic north. In this embodiment, azimuth is provided in terms of angles with magnetic north being 0 degrees and magnetic south being 180 degrees. In addition, the digital compass 908 can be implemented to modify the angle from magnetic north to the actual north angle as needed. In an application of the network 100 that covers a relatively small geographic area, the error between actual north and magnetic north is nearly uniform throughout the network 100. Therefore, in a preferred embodiment, this modification is not necessary or not implemented. But,
Such modifications may be implemented by digital compass 908 or controller 912, and are generally based on the geographic area in which node 108 resides. As described below, preferably, the digital compass 908 is １ ／ -〜, which is sufficiently accurate that the transceiver can initially point to the desired node 108, as described below. ° orientation is provided. Other accuracy ranges may be used, depending on the distance between nodes 108, the divergence of the transmit beam, and the aperture of the receiver.

Further, in one embodiment, the digital compass 908 can be provided with roll angle, pitch and yaw information for the installation fixture. Thus, in this embodiment, the digital compass 908 can be provided with information that is important for the leveling of the installation fixture, and thus for the level of the node 108 to which the installation fixture is attached. For example, the roll angle and pitch angle information can be used to determine whether the installation fixture is horizontal (and therefore node 108), or how far the installation fixture is from horizontal. This leveling information may be used to level the node or provided to a pointing system so that the deviation between the roll angle and the pitch angle of the node is taken into account in determining the pointing angle with respect to other nodes. it can.

In the embodiment shown in FIG. 15, digital compass 908 provides that information (ie, bearing) to controller 912. In some embodiments, the digital compass 908 can be implemented using a digital compass available from places such as Leica or KVH. The compass provides digital words that indicate the pointing of the device.

Although not necessarily required, the differential GPS 904 and the digital compass 908 may further provide a technician with a physical position and orientation, and if provided, a roll angle, a pitch angle, and yaw angle information from the device. A readable visual display can be provided. Providing such a function helps the technician to facilitate the installation process. For example, an installation technician can use roll angle and pitch angle information to level node 108. This display is displayed as GPS90
4 and the display provided on the digital compass 908, or
This can be done via a separate display provided on the installation fixture.

The pointing information for the note 108 can be determined based on the position and orientation information of the target node 108 connected to the position information of another node 108 in the network 100. The pointing angles for one or more transceivers in the node of interest 108 are determined with considerable accuracy using information in a simple triangulation. In other words, if the location of the relevant pertinent node 108 in the network 100 is known, simple geometric calculations can be performed within the node 108 such that the transceiver matches the desired other node 108 in the network 100. Can be determined where to direct a given transceiver of interest.

The controller 912 makes this determination by the appropriate node 108 in the network 100.
Assuming that the position information can be obtained, for example, it can be determined by the control device 912. Nodes associated with information about the target node 108 (i.e., nodes with which the target node directly interfaces (facing)) may be stored in the local store 928. Local storage 928, and also other information,
It can be used to store program instructions that allow the controller 912 to perform desired functions.

An operator interface 916 is included in the architecture exemplified in FIG. The operator interface 916 can be a simple and straightforward interface that allows a technician to control the installation fixture and enter data as needed. Thus, the operator interface 916 may consist of a simple keypad or other data entry device and also a display, but in a relatively straightforward implementation, the operator interface 916 comprises: There is only a start switch or power switch that can be used to allow the installation technician to activate the function of the installation fixture. Of course, the operator interface 916 is not required even if the installation fixture startup process can be automated. The above automated control is described below

The embodiment shown in FIG. 15 also comprises an optional auxiliary channel 920. Auxiliary channel 920 can be implemented similarly to auxiliary channel 816 described above. The auxiliary fixture 920 allows the installation fixture to communicate with other entities, such as a central office, independent of the network 100. Thus, on the auxiliary channel 920, which is preferably a wireless communication channel, the installation fixture may receive commands and other data from the central office and may provide data and possibly status information to the central office. it can.

Thus, in one embodiment, the controller 912 sends the location and heading information to a central office, which then communicates with one or more of the transceivers in the node 108. Pointing information can be determined. This pointing information can then be relayed back to the controller via the auxiliary channel 920 so that the installation fixture can direct the transceiver to the appropriate coordinate location. Further, location information for one or more nodes 108 to interface with the node of interest 108 can be provided to the installation fixture from the central office via the auxiliary channel 920. Thus, in this embodiment, the controller 912 can be used to calculate pointing information.

In these and also other scenarios to determine the correct pointing information, the installation fixture uses this pointing information and the various transceivers in the targeted node A communication link with another node 108 is set to the coordinate position. Accordingly, the installation fixture comprises the communication interface 916. In some embodiments, the communication interface can interface with a pointing mechanism in node head 654, either directly or via node base 65. Thus, the pointing information determined by the installation fixture can be used to control the pointing of the transceiver. In the sense of the embodiments described above, the installation fixture interfaces with the azimuth and elevation gimbal in the node head 654 to direct the transceiver to the appropriate coordinate position. Alternatively, the interface can provide information to base node 656 so that base node 656 can then control the pointing of node head 654.

The installation fixture is also installed on the network interface 92.
Consists of four. In this embodiment, the installation fixture uses the network interface 924 to allow the installation fixture to communicate with other nodes 108 via the network 116, including other entities including a central office or other entity. be able to. In some embodiments, the network interface 924 may be provided as an interface via the node base 656 or, if the node of interest 108 is not the root node 108A, via a temporary communication link 110 hops. it can. Needless to say, if the target node 108 is not set in the network 100,
The latter scenario is not feasible.

Although the installation fixture has been described in the example of the architecture shown in FIG. 15, those skilled in the art reading this description will appreciate that the installation fixture may be implemented in alternative architectures. Can be implemented and is not limited to the architecture shown in FIG.

FIG. 16 is an operational flowchart illustrating a process for determining node pointing or node components using an installation fixture, according to an embodiment of the present invention. Referring now to FIG.
In, the installer fixes node 108 to facility 104. This step can be performed, for example, by attaching the node 108 to a tower or other structure in the facility by bolts. Once the node is secured, the data drop can be attached to the interface node 108 to the facility 104 communication infrastructure. This is shown as step 934.

[0139] In step 936, power is applied to the node to enable the node to operate. During step 938, the installer can level the node using a mechanical level, such as a blister type level. The level may be a separate level leaning against the surface of node 108 or a level integrated with the node. Alternatively, levels can be provided for the installation fixture, and leveling can be performed after the installation fixture is fixed to the node 108. In some cases, it is preferred that leveling be performed on a fixture fixed to node 108, so that the mounting of the fixture after leveling does not offset the level of node 108.

In one embodiment, the installer can also use a mobile compass to provide an approximate orientation of node 108. This can be accomplished by adding a line or mark so that the installer can visually match the node 108. As explained above, this manual alignment step is not essential, since the installation fixture consists of means for accurately determining the orientation. Alternatively, depending on the implementation, it may be preferable to provide an approximate node orientation upon installation.

[0141] Once the node is secured to the facility 104, the installation fixture can be attached to the node. Various structural components can be provided to facilitate the attachment of the installation fixture to the node 108.
Preferably, the installation fixture can be mounted in a particular orientation with respect to the node 108, with index marks or other structures. It is also preferred that this installation be relatively rugged so that the installation fixture does not easily or substantially move relative to node 108. Thus, the position and orientation information, which can be determined utilizing the characteristics of the installation fixture described above, is relatively accurate to the node 108 without concern for errors caused by incorrect mounting. It can be applied to

In one embodiment, the mounting capacity of the installation fixture for the node 108 is provided such that the installation fixture can be removed from the node 108 after the initial installation is completed. Can be if you can,
Whether the position and orientation are affected by the removal of the installation fixture,
It is preferable to be able to carry out the removal without having to worry about moving due to it. This can be facilitated by the removable attachment between the installation fixture and the node 108 and the fixed and stable attachment of the node 108 to the facility 104. In some embodiments, the installation fixture may simply be placed on the node 108 to maintain a fixed attachment using friction and dead weight. In addition, grooves, pins or other structures or devices can be used to secure the mounting orientation of the installation fixture to the node.

[0143] In step 942, the installer initiates the installation process. This, in one embodiment, allows an installer to perform an installation fixture. This can be accomplished, for example, via an operator interface 916 that can be turned on by an installer or activate the installation fixture. As explained above,
This can be done with just a button or switch that activates the installation fixture once power is applied.

Alternatively, the operator interface 916 may provide this resilience by providing, for example, a keypad, keyboard, pointing device, or other data entry device through which data or instructions can be entered into the device. More complex inputs can be provided by operators who can provide.
In another embodiment, the auxiliary communication channel 920 once power is applied.
The installation fixture process can be started via.
Thus, in this embodiment, the installer can physically install node 108 and the installation fixture to power the device and begin tooling. After this, the central office may at any time initiate the remote installation procedure. Thus, the installer does not need to remain on site during the installation procedure. In this embodiment, the installer can return to the site at a later date to search for an installation fixture.

However, it is not necessary to use this alternative embodiment because the installation fixture process can be completed in a short time. As already mentioned, once the installation fixture process is completed,
The installation fixture can be removed. In an alternative embodiment, the installation fixture may remain permanently fixed to the node 108. However, since the node 108 is removably attached to the facility 104, the installation fixture does not need to remain fixed to the node 108. That is, in a preferred embodiment, once the location and pointing are obtained, the installation fixture can be removed from the scene.

In one embodiment, once the position and orientation information is determined from GPS 604 and compass 908, the installation fixture can be removed immediately. In this embodiment, information can be provided to the node base 656 and the node base 656 paging channel 816 can be used to interface with the central office to complete the pointing and alignment procedure for the node head 654. be able to. Alternatively, this paging channel or auxiliary channel 920 is used in the installation fixture to communicate with the central office and instruct the node head for the correct initial pointing.

In another embodiment, each node 108 comprises a receiver 904 and a digital compass 908 so that the controller of the node base 656 can perform an initial pointing operation. However, this alternative embodiment may be undesirable because it incurs the cost of CPS receiver 904 and digital compass 908 for node 108 having these components. Therefore, it is preferable to provide these components so that they can be removed through the installation fixture.

FIG. 17 is an operational flowchart illustrating an example of a process for starting a node 108 using an installation fixture in accordance with an embodiment of the present invention. Referring now to FIG. 17, in step 944, the installation fixture determines location coordinates using a location receiver. As described above, during this stage the X, Y and Z positions of the installation fixture can be determined, for example, using a GPS receiver. This provides the coordinate position of node 108 since the installation fixture is attached to node 108. In one embodiment, a location is provided relative to a reference frame that is fixed to the ground. Alternatively, location information can be determined for a reference frame for network 100. However, since GPS and other commercially available decision components are available at all times, the preferred embodiment uses such commercially available equipment.

During step 946, the installation fixture uses the digital compass 908 to determine the orientation of the node. Since the installation fixture is fixed and fixed to the node 108, determining the orientation of the digital compass on the installation fixture can be used to determine the orientation of the node 108. As described above, appropriate markings or appropriate mounting structures can be provided to ensure that the installation fixture and the target node 108 are properly and securely aligned with each other.

Once the parameters of the node (eg, location and orientation) have been determined during step 948, those parameters are transmitted to the central office. As described above, in one embodiment, these parameters are transmitted to the central office via the auxiliary channel 920. As described above, the auxiliary channel 920
Can be used, for example, as a paging channel or other wireless communication channel. Although hardwired channels can be implemented, this implementation is not feasible in most applications. Therefore, wireless communication for the auxiliary channel 920 is preferable.

In step 950, the central office determines the structure of the network 100 having the node. That is, the central office can determine which other node 10 in the network 100
8, it is determined whether the target node is linked via the communication channel 110. In certain embodiments, this determination may be performed by an application such as a network management application running on a server, workstation or computer in the central office. Further, the operator can also determine the network configuration.

Once the network configuration has been determined, the appropriate pointing angles for one or more transceivers in node 108 can be determined. These angles are used to set up channel 110 communication, pointing the coordinate position of the transceiver in the node of interest 108 to other nodes 108 in the network 100. As described above, in certain embodiments,
The network uses azimuth and elevation gimbal. Accordingly, these angles can be determined in terms of azimuth and elevation coordinates and provided to a node head 654 to direct the transceiver of the node head to the appropriate node 108 at a coordinate location.

As mentioned above, this angle determination can be made at the central office in the installation fixture or by the node base 656. The parameters used that can make an automated decision can consist of the node of interest, and also the location information of the node to which a given transceiver is interfaced.

[0154] In step 954, the node 108 performs a link acquisition. This is the embodiment described above where the transceiver on node head 654 is coordinately directed to the appropriate target node 108 using the pointing angle determined during step 952. . In one embodiment, this pointing accuracy as determined using the installation fixture is suitable for configuring node 108 for operation in network 100. Depending on parameters such as transmitter power, receiver operating range, transmit beam divergence, receiver aperture, and other parameters that depend on the type of communication equipment used to implement communication link 110, this A degree of pointing accuracy is sufficient, but higher pointing accuracy may be required in alternative embodiments or applications. Techniques for improving the pointing accuracy in this regard are described in detail below.

In some optical communication-based systems, a second transmitter and receiver pair may be provided at either end of the communication link, with the optical component at either end. Easy alignment. FIG. 18 is a diagram illustrating an example of optical communication. Here, referring to FIG. 18, the communication system includes a communication transmitter 1002 and a communication receiver 1004.
To optimize the performance of this system, communication transmitter 1002 has a relatively narrow beam waist and relatively little divergence.

For example, it is unpredictable whether the laser communication system will have a beam divergence of 1.5 milliradians (mrads) and a field of view of 3 degrees at the receiver 1004. At the receiving end, such a system is difficult, if not impossible, to manually align, since a small degree of divergence results in a very narrow beam waist. Thus, in one embodiment, the second transmitter 1008 and the second receiver 10
10 can be added to the communication link. Preferably, the second transmitter 1008 is operated at a different wavelength than the communication transmitter 1002 and has a wider beam divergence. In some cases, it depends on how much power is required to transmit on the link and how quickly the installer at the other end of the link wants to pick up the receiver. , The divergence of the second transmitter 1008 can be a factor 10 to 20 times greater than the communication transmitter 1002.

[0157] Often, the second receiver 1010 is a spatial receiver, such as a charge-coupled device (CCD) quadrature detector or other detector that provides spatial information about the received signal. Thus, information can be determined where the transmitted matched beam from the second source 1008 hits the receiver 1010. Using the information from the spatial detector, the transmitter or receiver can be adjusted so that the transmitted beam strikes the desired location of the spatial detector.

In general, this is done by looking at the center of the beam defined by the output roll-off level. Thus, the center of the beam can be selected, for example, centered on the spatial detector 1010. However, a disadvantage of this system is that additional components, namely a second transmitter and a second receiver 1010, need to be provided at each transceiver to facilitate proper alignment. .

In one embodiment, a new node 108 in the network 100 is staring at its receiver at each of the existing nodes to which it is thought to be connected. For many applications, the receiver does not need to perform a scan of the resulting acquisition because the uncertainty cone is smaller than the field of view of the receiver. Thus, the fixed receivers and transmitters of the existing nodes can be scanned to center the beam or improve the accuracy of the pointing. One advantage of this is that it runs fewer motors on each new node, so less power is required.

With the advantages provided by the installation fixture, the initial match can be made so accurate that the second transmitter 1008 and the second receiver 1010 are not required. For example, transmitting the divergence of a 1.5 mrads beam, receiving a 3 degree field of view, and having a node-to-node spacing of 15 meters, etc., with the accuracy levels provided by the differential GPS 904 and the digital compass 908, are sufficient The pointing angle to be determined with accuracy can be such that the transmitted beam from the communication transmitter 1002 is scanned and within the 3 degree field of view of the communication receiver 1004.

[0161] Therefore, link acquisition can be performed by communication components without the need for the second transmitter 1008 and the second receiver 1010. However, it is often preferred that the pointing accuracy be improved over that obtained in the initial capture. Even if the level of accuracy and the receive / transmit parameters of the components of the installation fixture are 15 meters apart, there is an uncertainty cone of about 10 degrees.
This equates to about 400 spots where a 1.5 mrads transmit beam can be struck on the received detector.

As noted above, in one or more embodiments, a spatial detector may be provided to determine the transceiver's match in the communication link and adjust this match. Can provide information. Spatial detectors are available for both optical and wireless detection, and in many aspects are very similar in function. As mentioned above, spatial detectors such as charge coupled device (CCD), optical quadrature cell detectors or other spatial detectors can be implemented in optical embodiments.

An optical orthogonal cell detector will now be described. However, after reading the description of this optical quadrature cell detector, it will become apparent to one skilled in the art how to implement a spatial detector using other optical or wireless detectors. The quadrature cell detector and associated circuitry converts the light striking the detector to an optical current, which is then converted to a voltage. This voltage is amplified and distinguished from the background light source. Thus, the quadrature cell detector and associated circuitry generates a voltage proportional to the received force, azimuth and elevation of the pointing error. In one or more embodiments described below, modulation may be added to the matching signal to distinguish the matching signal from other noise signals, such as background light or extraneous light sources. it can.

An example of an orthogonal cell detector is shown in FIG. In this example, the orthogonal cell detector is divided into four segments, which are preferably the same size. In one embodiment, the effective area of all sizes is 5x5 mm, although other sizes are possible. Light impinging on the surface of the detector generates a photocurrent that is proportional to the illuminance, and thus detects the current from each of the orthogonal
The spatial location of the beam striking 2 can be determined. Within the detection circuit, a difference amplifier can be used to determine the relative signal strength based on the photocurrent generated from each of the four segments. This information can be provided to the processor to determine azimuth and elevation errors, as well as the sum of the peaks, which can be used for error value normalization and fault diagnosis.

Thus, in one embodiment, a beam splitter is provided in the light receiving path to “kick-off” a portion of the received communication beam and provide this beam to the spatial detector. . In one embodiment, a four percent beam splitter is used to utilize four percent of the received signal power and provide it to communication receiver 1004. In one embodiment, the diameter of the beam splitter is
Detecting a signal with a spatial detector as long as the transmitted beam is within the received aperture, regardless of pointing accuracy, larger than the diameter of the receiver aperture where the beam splitter is located Is available.

In one embodiment, the spatial detector can be implemented using, for example, a CCD having multiple “pixels” or a quadrature detector or other spatial detector. In this system, when the node is taken in, the transmit beam hits the node,
It can be implemented to reside long enough to focus the beam on the spatial detector. The information from the spatial detector is processed by a processor, such as a controller in the node base 656, to detect pointing errors based on how far the beam impinging on the received spatial detector is off-center. Can be determined. In certain embodiments, this information can be fed back to a pointing device for the transmitter so that the pointing of the transmitter can be adjusted to the center of the beam above the spatial detector. A similar spatial detector can be provided with a receiver at the transmitter so that pointing can be adjusted from both directions.

FIG. 20 shows a beam split beam reflected from a spatial detector behind the main objective. Referring now to FIG. 20, a light beam 1022 from the transmitter strikes an objective lens 1034. Light from the objective lens is collected on the spatial detector 1036. As described herein, the spatial detector 1040 can then be used to determine if a pointing error is in the system.

Even with the use of spatial detectors, pointing errors can be introduced due to noise or unwanted light sources that can introduce noise into the system. For example, at night, a street light in the field of view of the receiver 1004 may combine with the communication signal received on the spatial detector, causing the system to erroneously assume that there is a pointing error. FIG. 21 is a diagram illustrating a phenomenon in which an undesired light source may cause a pointing error. The example shown in FIG. 20 is shown with quadrature detector 1022. However, after reading this description, those skilled in the art will appreciate that this scenario can occur with CDD and other spatial detectors.

Here, referring to FIG. 21, the quadrature detector 1022 includes four quadrants A, B, and C.
And D. Transmit beam 1024 is output from quadrant detector 10 as a result of previous matching.
Focused on 22. However, additional light sources, as extraneous light sources 1026,
Picked up by quadrant detector 1022. The extraneous light source 1026 may be, for example, a street light, sunset, headlights of an oncoming car, or other undesirable light source. Depending on the illuminance of the light source, the filter provided in the light receiving path may not be sufficient to reduce the signal power of this unwanted light source 1026.

Thus, the undesired light source 1026 can be bent to some extent as a result of the signal processed from the quadrant detector. Specifically, in the example shown in FIG. 20, an extraneous light source 1026 causes the system to think that the transmitter is pointing more toward quadrant B. Thus, the pointing can be adjusted even if the communication beam 1024 is accurately concentrated. As a result, the full power from the light source 1026, unrelated to the communication beam 1024,
The communication beam 1024 is effectively off-center, while the communication beam 1024 is away from the center.

One way to solve this problem is to provide a method for the spatial detector or other matched detector and its associated electronics to distinguish between the communication signal 1024 and the extraneous signal 1026. is there. For purposes of matching, these two signals can be distinguished so that unwanted unrelated signals 1026 are effectively ignored. Since a communication signal has data that is modulated on the signal, one technique is to use this modulation to distinguish between the two signals. However, orthogonal cells and CCD
Such a spatial detector generally has a low-frequency response. Because most communication signals are modulated at a relatively high rate, this modulation is not detected by the spatial detector.

For example, in one embodiment described above, data is transmitted over communication link 1
10 at a rate of 622 MBPS. This is well above the cutoff frequency of the relatively low frequency response of the spatial detector. In fact, many current spatial detectors exhibit a frequency response of 100 kHz or less. Therefore. Since a communication signal, such as 622 MBPS, is sufficiently higher than this low frequency response, this signal is like a DC bias to the spatial detector. Thus, in one embodiment of the invention, the low frequency tone is modulated into the communication signal so that the low frequency tone can be detected by the spatial detector.

In some embodiments, the tones can be generated by a microprocessor, but to avoid unnecessary use of the processor, use “for example, using an electric field programmable gate array (FPGA). Generated in hardware.

FIG. 22 is a table showing an example of a data signal that can be received by the receiver. Because the signal is a digital signal, one embodiment is 622 megabits per second, the signal appears at the receiver in a series of ones and zeros. Thus, FIG. 22 is an example 1 and 0 data stream. When this data stream is modulated to a low frequency carrier signal, the result is similar to the example shown in FIG. FIG.
, A digital data stream 1144 is modulated onto a low frequency carrier 1148. As described, in one embodiment, the low frequency carrier is at a frequency of about 10 kilohertz. Therefore, this frequency is within the frequency range of the frequency response of the spatial detector. Thus, the processing circuitry of the spatial detector can distinguish between this signal and a noise source that typically appears as a DC level signal.

[0175] In certain embodiments, it is important to ensure that the transmit beam always meets eye safety requirements. Thus, in some embodiments, modulation of digital data onto a carrier signal results in a substantial increase in transmitter power. As such, such an increase may cause the transmitter power to rise beyond eye safe ranges. For example, in some applications, modulation of digital data onto a kilohertz carrier causes a real increase in output power by a factor of two. Therefore, the transmitter power will need to be reduced by 3 dB to compensate for this rise. Such a reduction in transmitter power is not desired because this phenomenon can potentially affect the ability to detect digital data. Thus, in one embodiment, the modulation of the data onto the DC carrier is only performed periodically. This is possible because it is not necessary that pointing adjustments can be made at high frequencies. In effect, tracking algorithms typically run relatively slowly compared to the data signal. Thus, the tracking algorithm is performed with a duty cycle and the correction is performed relatively infrequently.
For example, in one embodiment, the tracking algorithm is executed on ten cycles of a 10 kilohertz signal. Thus, the data is only modulated onto the low frequency signal at intervals of 5 to 10 seconds. For example, if the duty cycle is 1%, 0.10%, or 0.01%, extra power is added to the transmitter for only a short period of time. Therefore, the laser power only needs to be reduced, a small part of the total power. For example, at a duty cycle of 0.01%, the laser power need only be reduced by a factor of 0.01%. This is possible because the eye safety range is determined for signals passing through a time period as opposed to being determined instantaneously.

[0176] In one embodiment, the node 108 has three nodes for good performance in severe weather conditions.
It is designed to have a link margin of 5 dB to 45 dB. To provide this margin in harsh weather conditions, the detector may receive light above and beyond its dynamic range in sunny weather. In this way, one or more additional features can be included to maintain light levels that are within the dynamic range of the detector.

In some embodiments, the transmitted beam is decentered such that the power reaching the detector can be attenuated without using additional optical elements such as neutral density (ND) filters. This embodiment is particularly useful in scenarios where the transmitted beam has a Gaussian profile. In such an application, a portion of the signal, including the highest power portion, may be directed away from the receiver while a lower portion of the signal remains on the detector. As such, the signal is in control to retreat within the dynamic range of the receiver. There are several techniques that can be used to achieve this "eccentric" pointing of the transmitted beam

FIG. 24 is an operational flow diagram illustrating a process for eccentricizing a transmitter to guarantee excessive transmitter power according to an embodiment of the present invention. Step 1102
Then, the receiver receives the signal from the transmitter.

[0179] The received transmit power is determined in step 1104 by the signal strength measurements.
Received signal strength can be used to determine whether the transmitter is operating at any power level such that the power level is too high or too low given current link operating conditions. For example, a signal strength determination may indicate that the receiver is saturated because the transmit power is too high. As such, it is desired to reduce the transmission power level. Alternatively, the receiver may determine that the received power level is too low to allow for accurate detection of the transmitted data.
This can occur, for example, if the weather conditions have been substantially degraded enough to affect the transmission of the signal from the transmitter to the receiver. As such, the receiver may want to increase the effective transmit power.

In one embodiment, the laser power and the receiver dynamic range are equal to o at nominal output power.
Using n-center pointing, the receiver is selected to be able to receive the transmitted signal even in the worst case expected weather conditions. As such, as the weather begins to clear, the received signal strength will begin to rise toward the saturation point. Stage 110
At 6, the receiver informs the remote transmitter that the power level is too high and needs to be reduced. In certain embodiments, as described above, the power level is substantially reduced by pointing the transmitter away from the center of the receiver. In this way, a portion of the transmitted beam is outside the aperture of the receiver, resulting in the receiver receiving only a percentage of the power actually transmitted. As such, the signal is
It can be adjusted to fall within the dynamic range of the receiver. The level of power decay is a function of the magnitude of pointing errors introduced into the transmitter system.

In some embodiments, the initial laser power setting can be determined from the initial retroreflector signal used to perform the coarse acquisition. Because the path is symmetric, this decision may apply to both transceivers associated with communication link 110.

[0182] The manner in which information is communicated to the transmitter to decenter pointing can be implemented according to many different embodiments. In embodiments where communication link 110 is implemented to transmit packetized data between nodes 108, additional status packets can be inserted into the packet stream. This additional status packet could possibly be used to provide this power level measurement indication as well as additional or alternative status or collateral computation information. Thus, using this embodiment, the receiver may use in-band signaling to immediately notify the transmitter over communication link 110 that the transmit power actually needs to be adjusted. Can be.

Further, in an alternative embodiment, a paging channel or other communication channel could be used to return this information to the transmitter. However, this embodiment is not preferred because it requires additional communication between the receiver and the transmitter. It is preferred that existing communication links 110 take advantage of the additional bandwidth by adding child status packets to the transmission.

The receipt of status information indicating that power needs to be adjusted can be provided directly to node head 654 so that the node head can adjust its azimuth or elevation gimbal. The signal is provided to the node base 658 instead so that the controller in the node base 656 can determine the amount of error, introduce the appropriate gimbal, and drive the appropriate gimbal accordingly. These embodiments can be implemented using multiple data communications between the node head 654 and the node base 656. They can be implemented in the system using other communication schemes between the node head 654 and the node base 656.

In one embodiment, the system can be implemented to wait until the receiver is in saturation mode before requesting the transmitter to introduce a pointing error into the system. Alternatively, the system can be proactive and programmed to look ahead to predict if the receiver will saturate and before actual saturation occurs. In this way, the upward trend in the power of the received signal may be extrapolated in advance to predict saturation, and the transmitter adjusted accordingly. Alternatively, various threshold ranges can be set within the receiver dynamic range, and the transmitter has incrementally adjusted according to the range over which the power of the received signal falls.

For example, in the lowest threshold range of the dynamic range of the receiver, the transmitter
It is pointed to the highest degree of accuracy so that the peak of the cian signal is centered on the spatial detector. When the power level of the received signal transitions to the next threshold range,
The transmitter can point off-center by a specified amount to reduce the effective received signal strength. This can continue if the amount of skew at the transmitter is performed based on the magnitude of the force in the received signal.

In an alternative embodiment, the receiver or the transmitter, or both, may have a filter inserted into the transmission path, for example, a neutral density (ND) filter. However, this embodiment makes use of additional materials, as well as mechanisms for driving the filler in and out of the signal path. Further, due to the varying degree of attenuation, multiple filters may actually be needed.
As such, this alternative implementation requires additional hardware, which adds additional cost and complexity to the system. On the other hand, adding pointing errors to the system can be performed using existing pointing mechanisms provided within node head 654. Therefore, this embodiment is preferred.

Yet another alternative is to use an electronically controlled N with varying degrees of attenuation.
A D filter can be used. However, this embodiment also takes advantage of additional material added into the channel.

In addition to this technique for decentering the laser, the signal from the receiver is sent back to the transmitter to adjust the transmitter's bias level, thereby reducing its transmit power. Again, this technique may use an in-band signaling technique that allows data or data packets to be inserted into the communication link between the receiver node 108 and the transmitter node 108, or another in-band signaling technique. Alternatively, another communication channel, such as an auxiliary channel, can be used.

Preferably, in implementations where a look-off is implemented, centered pointing without performing unnecessary search or generation algorithms so that useful power can be increased again when needed. There are techniques for storing values.

As described above, in one embodiment, a spatial detector can be used to determine the pointing accuracy of the transmitter with respect to the receiver. The data from the spatial detector can be used to improve pointing accuracy or otherwise improve it.
Used to provide feedback on pointing. An alternative embodiment that avoids the use of spatial detectors can be implemented to determine pointing accuracy. If the transmit beam has spatial features, this information can be used to obtain information about these spatial features and to help determine pointing accuracy. This information can be used to improve the pointing accuracy of the system.

For example, a transmit beam having a Gaussian profile ideally has a peak energy level at the center of the beam. This energy gain gradually deviates from the center point initially, and then more dramatically, until it approaches the minimum signal level. Because of these spatial features, pointing accuracy can be determined based on the relative energy level of the received signal. Generally, the transmitted beam is slewed across the detector and the relative signal strength is measured during this process.

Simply stated, as the transmitter is turned, the receiver will tell the transmitter whether the signal strength is increasing or decreasing, and thus the transmitter will be closer to the center. Or even further away from the center. The receiver looks for the pointing angle that produces the highest signal strength. This angle is considered to be the angle associated with accurate pointing for the transmitter. In some embodiments, this can be achieved using other communication channels, including, for example, auxiliary channels.

FIG. 25 is an operational flow diagram illustrating a process for utilizing a beam profile to determine pointing accuracy according to an embodiment of the present invention. Referring now to FIG. 25, in step 1204, a beam is transmitted from a transmitter at a first node 108 to a designated receiver at a second node 108. In some embodiments, the transmit beam may be a communication beam used to establish a communication link 110 between nodes 108. The designated receiver 10 at the receiving node
8 measures the received signal strength at the receiver.

At step 1208, the transmitter is turned so that the pointing of the transmit beam is changed. The receiver re-measures the signal strength so that it can determine if the reorientation improved or degraded the pointing of the transmitter. In some embodiments, the turning can be performed in steps with measurements taken at the end of each step. In an alternative embodiment, the turning is continuous and the measurement is taken as the turning occurs. Whether step-wise or continuous, the speed of the turning can be chosen based on the speed at which the signal strength can be measured and the feedback loop used to control the transmit beam.
Operation is described in terms of a step-wise implementation. After reading this description, it will become apparent to a person of ordinary skill in the art how to implement this process using a continuous turning embodiment.

In step 1210, it is determined whether the signal strength is lower or higher than a past measurement. In other words, it is determined whether the signal strength has increased or decreased as a result of the turning operation. In one embodiment, the determination is
The current received signal strength is made at the receiver to be compared to previously received signal strengths to determine relative changes. In this embodiment, the receiver can provide a feedback signal to the transmitter indicating this change or a delta in received signal strength. In an alternative embodiment, the actual measurement is relayed back to the transmitter and the transmitting node 108
It can be determined whether the current signal strength measurement is lower or higher than the previous signal strength measurement.

In one embodiment, in-band signaling is used to provide information to transmitting node. Using in-band signaling, data indicating the received signal strength (actual or delta) is inserted into the communication link between the nodes. In some embodiments, additional packets are inserted into the communication channel between affected nodes 108, or additional data is inserted into existing packets transmitted between nodes 108. Alternatively, an auxiliary channel or other communication path between nodes 108 can be used to relay this information.

In step 1210, if the received signal strength is determined to be higher, this is an indication that the transmitter is turning in the correct direction to provide more accurate centering. As such, in step 1222, the transmitter is further turned. At step 1210, the signal strength is re-measured to determine whether the signal strength has increased further or has instead decreased. If the signal strength further increases, this loop between steps 1210 and 1222 continues until a deterioration in the received signal strength is detected. As mentioned above, in one embodiment, this is
The transmitter can be steered by a fixed amount, measurements can be taken, decisions can be made, and steps can be taken to provide additional stepwise turns until a maximum is reached.

On the other hand, if it is determined in step 1210 that the new signal strength at the receiver is lower than the past signal strength, this is an indication that the transmitter is being turned in the wrong direction. . Thus, at step 1218, the transmitter is commanded to reverse the direction of the turn and turn back in the other direction. If a past command also instructed the transmitter to reverse direction, this is a sign that the transmitter is approximately centered. As such, no additional turning needs to occur,
The transmitter can return to its past pointing angle.

In one embodiment, the procedure is repeated for both the azimuth and elevation axes so that the transmitter is centered to the degree of accuracy possible based on the step size of the gimbal locator. be able to. Since the reorientation of both the azimuth and elevation axes results in a reversal in two nearly water-reserving directions, this is to center the beam to the degree of accuracy possible with the gimbal positioning system. Is enough.

As with the spatial detector, this profile pointing technique corrects for pointing errors that might otherwise occur during the initial integration of nodes 108 in the network 100 or during aspects of the nodes 108. To be able to run. Such errors may occur, for example, as a result of expansion and contraction due to temperature changes, and errors introduced over time as a result of inaccuracies in hardware mechanisms may include, for example, earthquakes, nodes 10
8 changes the relative position of one node with respect to another node as a result of anchoring of a building or tower mounted thereon, or other phenomena that cause displacement of node 108 relative to another node 18.

In one embodiment, the redirection step size controlled by the transmitting gimbal is:
For example, it may be 150 microradians (μrads). This is 1.
One tenth of the divergence of the 5 mrad divergent beam. The amount of time spent at each stage is
Depends on tracking bandwidth. In some embodiments, the transmitter can move as fast as five steps in a half second. In this way, within just a few seconds, according to the invention, the transmitter can be centered to ± 150 μrads.

As a result of this profile pointing mechanism, the need to include a spatial detector at the receiving end of communication link 110 has been eliminated. In this way, the hardware required to implement this spatial detector, along with its associated space constraints and costs, can be avoided.

Further, there is no need to include a beam splitter to extract a part of the reception beam for pointing detection.

In certain scenarios, the pointing accuracy initially obtained using the installation fixture as described above, or initially obtained by manual means, is sufficient to allow for an initial acquisition of the node. May not be. This is because the pointing uncertainty relates to any location uncertainty divided by the range between nodes. Thus, the pointing uncertainty increases as the range decreases.

For example, in the implementation of the previous example, where the receiver field of view is 3 ° at a distance greater than about 70 meters, the initial pointing decision may not bring the transmitter within the range of the field of view of the receiver. There is. As such, alternative acquisition techniques using retroreflectors can be utilized as described below.

In certain embodiments, one or more retroreflectors or corner cubes
cube) at the node. Alternatively, a reflector tape having properties similar to those of a row of retroreflectors or square cubes can be used. As is known to those skilled in the art of optical technology signals, the concept of a retroreflector is to return or reflect a transmitted beam back to its source. Retroreflectors typically have relatively high acceptance angles (10 to 20 degrees or more), and thus:
In situations where the pointing accuracy would not be sufficient to illuminate a receiver with a 3 ° field of view, the optical beam would be accepted and returned. Once the retroreflector is acquired, the transmit beam is centered on the retroreflector and then, with an appropriate offset angle, the designated receive at one of the node heads 654 in the receive node 108 You can turn to the machine.

[0208] The retroreflector can be obtained as a bespoke or off-the-shelf product. Retroreflectors can be used at varying levels of quality, from simple reflector tape type products to accurately fabricated high optical quality retroreflective pairs.

FIG. 26 is an operational flow diagram illustrating one process for using a retroreflector to acquire a node 108 according to an embodiment of the present invention. Step 1252
Then some form of coarse pointing will cause the transmitter beam to
Executed to almost point to 08. This rough pointing uses the installation fixture of the previously described embodiment,
It can be accomplished in a number of ways, including manual pointing or other coarse pointing techniques. Binoculars, viewing instruments, or other visual display aids can be mounted on the node or on the installation fixture to facilitate manual pointing. Although these techniques may be sufficient to illuminate the receiver with certain geometries, these relatively coarse techniques are not enough to acquire a node receiver early There are exceptional geometries.

In some embodiments, this coarse pointing may not be enough to make the retroreflector suitable. Thus, in step 1256,
The transmit beam is scanned to search for retroreflectors. Once the scanning beam is fixed on the unique signal from the retroreflector, at step 1258, the transmitter is centered on the acquired cube. In one embodiment, this is achieved similar to the profiling technique described above, in which the transmitted beam is scanned over an angular cube to find a point where the maximum signal strength is returned to the receiver at the transmitter location. Can be.

Here, the transmitter starts scanning in another direction to actually illuminate the receiver with respect to the designated transceiver at node 108. This is indicated by step 1260. In one embodiment, this scan is in a worst case 10x10 degree uncertainty field and can be performed well within one minute. Once the detector is acquired, the transmit beam can be centered on the detector at step 1264. Centering techniques may include the spatial detector and beam profile techniques described above. In this way, according to this technique, a corner cube or other similar reflection pair can be directed to perform a coarse acquisition and fine tuning can occur. In one embodiment, the degree of accuracy obtained using the installation fixture is sufficient to illuminate the retroreflector, if not enough to illuminate the receiver. Thus, in this embodiment, no manual or coarse pointing is required.

In one embodiment, the retroreflector is mounted on a node, on an installation fixture, or some other location where the pointing difference between this location and the actual receiver is known. Can be. As such, once the retroreflector has been acquired, the beam can be directed to the receiver.

Since the offset between the retroreflector and the receiver requires different transmitter angle offsets in different ranges, the range between nodes 108 should be such that the correct transmitter angle offset is cut off by hair. It is. In one embodiment, the motor drive system comprises:
There is a function of one tenth of the transmitter beam width resolution so that it can accurately point the transmit beam at the receiver. Again, once the receiver picks up the signal, a communication link can be established between the two nodes via the phase shift channel 100. The pointing angle optimization itself can then begin.

While various embodiments of the present invention have been shown and described above, it should be understood that they have been presented by way of example only, and not limitation. It should be apparent to those skilled in the art that many other embodiments are possible without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example communication network according to an embodiment of the present invention.

FIG. 2 is an operational flow diagram illustrating a process in which a communication network operates according to an embodiment of the present invention.

FIG. 3 is a block diagram illustrating an embodiment in which a service provider may use a SO in order to interface with a root node in accordance with an embodiment of the present invention.
Use the NET ring.

FIG. 4 is an operational flow diagram illustrating a method for utilizing the architecture shown in FIG. 3 to provide communication to an end user in accordance with one embodiment of the present invention.

FIG. 5 is a diagram illustrating an example software protocol architecture for performing ATM / SONET, such as that shown in FIG.

FIG. 6 is a diagram illustrating functionality provided at a root node according to an embodiment of the present invention.

FIG. 7 is a diagram illustrating functionality provided at a destination node for interfacing between the node and user equipment at a facility in accordance with an embodiment of the present invention.

FIG. 8 is a diagram illustrating a specific example of a node according to an embodiment of the present invention.

FIG. 9 is a block diagram illustrating a logical breakdown of components that can be included in an example node head according to an embodiment of the present invention.

FIG. 10 is a block diagram illustrating a specific example of a communication receiver circuit according to an embodiment of the present invention.

FIG. 11 is a block diagram illustrating a specific example of a transmission circuit according to an embodiment of the present invention.

FIG. 12 is a diagram illustrating a specific example of a beacon laser according to an embodiment of the present invention.

FIG. 13 is a block diagram illustrating a logical breakdown of components of a node-based example in accordance with one embodiment of the present invention.

FIG. 14 is a diagram illustrating an example of an auxiliary channel using the ReFlex 25 or 50 protocol according to an embodiment of the present invention.

FIG. 15 is a block diagram illustrating a specific example of an installation fixture according to an embodiment of the present invention.

FIG. 16 is an operational flow diagram that uses an installation fixture to determine the pointing of a node or its components according to an embodiment of the present invention.

FIG. 17 is an operational flow diagram illustrating an example process by which a node can be started using an installation fixture in accordance with an embodiment of the present invention.

FIG. 18 is a diagram illustrating an example optical communication system that uses a second transmitter / receiver pair to align optical components.

FIG. 19 is a diagram illustrating an example quadrant detector in accordance with an embodiment of the present invention.

FIG. 20 is a diagram showing a beam spectrum reflected back to a spatial detector behind a main objective lens.

FIG. 21 is a diagram illustrating a phenomenon where an undesired light source can potentially cause a pointing error.

FIG. 22 is a diagram showing an example of a data signal that can be received by a receiver.

FIG. 23 is a diagram illustrating the modulation of an example data signal onto a low frequency carrier in accordance with an embodiment of the present invention.

FIG. 24 is an operational flow diagram illustrating a process of de-centering a transmitter to compensate for excessive transmitter power according to an embodiment of the present invention.

FIG. 25 is an operational flow diagram illustrating a process for utilizing a beam profile to determine pointing accuracy according to an embodiment of the present invention.

FIG. 26 is an operational flow diagram illustrating a process for utilizing a retroreflector to acquire a node according to an embodiment of the present invention.

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SL, SZ, TZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CR, CU, CZ, DE, DK, DM, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID , IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, TZ, UA, UG, US, UZ, VN, YU, ZA, ZWF terms (reference 5K002 DA09 FA03 FA04 5K033 DA06 DA20

Claims (48)

[Claims] An installation fixture for arranging and aligning nodes in a network, comprising: a position determining device configured to determine a position of the installation fixture; A digital compass configured to determine the orientation of the ration fixture; and providing the location and orientation information to a processor to determine a pointing of one or more transceivers in the node based on the location and orientation information. Fixture comprising a communication interface configured as described above. 2. The installation fixture according to claim 1, wherein said positioning device is a GPS receiver. 3. The installation fixture according to claim 1, wherein said positioning device is a differential GPS receiver. 4. The installation fixture of claim 1, wherein the digital compass is further configured to determine a roll angle and a pitch angle of the installation fixture. 5. The installation fixture according to claim 1, further comprising an alignment structure for facilitating alignment between the installation fixture and a network node. 6. The installation fixture according to claim 1, further comprising an operator interface. 7. The installation fixture according to claim 1, wherein said operator interface comprises a data input device. 8. The installation fixture according to claim 1, wherein said operator interface further comprises a display device. 9. The installation fix of claim 1, further comprising a communication interface configured to interface with a pointing mechanism at a network node to direct one or more node transceivers in a proper direction. Cha. 10. The installation fixture according to claim 1, further comprising a network interface. 11. The installation fixture according to claim 1, wherein said communication interface is an internal communication path, and said processor is a processor of said installation fixture. 12. The installation fixture according to claim 1, wherein said communication interface is an external communication path, and said processor is located remotely from said installation fixture. 13. The installation fixture of claim 12, wherein said processor is part of a processing system located at a central office. 14. The installation fixture of claim 12, wherein the communication interface is at least one of a paging channel, a wireless communication channel, and a hardwired communication channel. 15. A system for locating and aligning nodes in a network, comprising: means for locating nodes within the network; and means for determining node orientation within the network. And means for determining pointing of one or more transceivers at the node based on the position and orientation information. 16. The means for determining pointing of the one or more transceivers comprises: transmitting location information from the means for determining location to a remote location from which pointing information is determined; The system of claim 15, comprising communication means for receiving the pointing information from a remote location. 17. The means for determining the pointing of one or more transceivers comprises the step of determining the pointing of at least one transceiver at a node based on the location of the installation fixture within the network. 16. The system of claim 15, comprising processing means in the tea. 18. The method according to claim 1, wherein the means for determining a position is a GPS receiver.
5. The system according to 5. 19. The system of claim 15, further comprising means for determining a roll angle and a pitch angle of the node. 20. The system of claim 15, wherein said system is an installation fixture configured to be implemented on a node inside a network. 21. The system of claim 20, wherein said installation fixture comprises means for fixedly aligning the installation fixture with said node. 22. The system of claim 15, further comprising interface means for allowing an operator to operate the installation fixture. 23. The system of claim 15, further comprising communication means for providing pointing data to a pointing mechanism at a network node to direct one or more node transceivers. 24. A method for aligning a network node, comprising: determining a location of an installation fixture installed on a network node; determining an orientation of the installation fixture; A method comprising determining a pointing of one or more transceivers at a node based on position and orientation information. 25. The method of claim 24, further comprising installing the installation fixture on the node. 26. Determining the pointing comprises transmitting the location of the installation fixture to a central office,
26. The method of claim 24, wherein the central office determines pointing information for a node, and comprises receiving the pointing information from the central office. 27. The method of claim 24, further comprising instructing a transceiver of a node to point according to the pointing information. 28. Determining the pointing of one or more transceivers at the node comprises determining a location of the node relative to other nodes in the network based on a location of the installation fixture; 25. The method of claim 24, comprising determining a pointing angle of a given transceiver in the network with respect to other nodes based on its position with respect to the node. 29. The method of claim 28, wherein the pointing angle is determined based on an orientation of the node with respect to an installation fixture. 30. A program readable by one or more machines that explicitly includes a program of instructions executable by one or more machines for performing the method steps for aligning a network node. A storage device, the method comprising: determining a location of an installation fixture installed on a network node; determining an orientation of the installation fixture; and based on the location and orientation information. Determining the pointing of one or more transceivers at the node. 31. The program storage device of claim 30, wherein the method steps further comprise installing the installation fixture on the node. 32. The step of determining the pointing includes transmitting the location of the installation fixture to a central office.
31. The program storage device of claim 30, wherein the central office determines pointing information for a node, and receiving the pointing information from the central office. 33. The program storage device of claim 30, wherein the method steps further comprise: instructing a transceiver of a node to point according to the pointing information. 34. Determining the pointing of one or more transceivers at the node comprises determining a location of the node relative to other nodes in the network based on a location of the installation fixture; Determining a pointing angle of a given transceiver in the network relative to other nodes based on its location relative to the node. 35. The program storage device according to claim 34, wherein the pointing angle is determined based on an orientation of the node with respect to the installation fixture. 36. A computer program product for use with a computer system, the computer program product having computer readable program code means embedded within a medium to facilitate alignment of the network node to the computer system. Said computer readable program code means comprising said medium readable by said computer, said computer readable program code means for determining the location of an installation fixture, and said installation fix within a network. Computer readable program code means for determining the orientation of the channel, and one or more transactions at the node based on the location and orientation information. A computer program product comprising a read program code means according to a computer for determining the pointing over server. 37. Computer readable program code means for determining the pointing of the one or more transceivers comprises means for determining a location from the means for determining a location to a remote location from which pointing information is determined. 37. The computer program product of claim 36, comprising means for transmitting information and receiving said pointing information from said remote location. 38. The computer readable program code means for determining pointing of one or more transceivers comprises pointing to at least one transceiver at a node based on a location of an installation fixture within a network. 37. The computer program product of claim 36, comprising computer readable program code means in the installation fixture for determining 39. The computer program product of claim 36, further comprising computer readable program code means for determining a roll angle and a pitch angle of the installation fixture. 40. The computer readable medium of claim 36, further comprising computer readable program code means for providing pointing data to a pointing mechanism at a network node to orient the one or more node transceivers. Computer program product. 41. A system for arranging and aligning nodes in a network, wherein the fixture comprises a position determining device configured to determine the position of the node. A digital compass configured to determine the orientation of the node within the network; and providing the location and orientation information to a processor, and pointing to one or more transceivers within the node based on the location and orientation information. A communication interface configured to determine the system. 42. The system according to claim 41, wherein said position determining device is at least one GPS receiver or an active GPS receiver. 43. The system of claim 41, wherein said digital compass is further configured to determine a roll angle and a pitch angle of a node. 44. The system of claim 41, further comprising an alignment structure that facilitates alignment of a node with a network node. 45. The system of claim 41, further comprising an operator interface. 46. The system of claim 1, further comprising a communication interface configured to interface with a pointing mechanism at the network node to direct the one or more node transceivers in the proper orientation.
(41 ?: translator's note) 47. The system of claim 41, wherein said communication interface is an internal communication path and said processor is a processor of said node. 48. The system of claim 41, wherein said communication interface is an external communication path and said processor is located remotely from said node.