A system for use in a drilling operation that includes uphole electronic equipment and a drill string suspended in an earth borehole, a section of wired drill pipe that is part of a communication link between a downhole tool and the uphole electronic equipment, an interface for communicating between the section of wired drill pipe and a communication source/destination. The system includes a housing having a generally cylindrical outer shape which has a passage there through. The housing has a WDP end connectable to the section of wired drill pipe and a further end connectable to the communication source/destination. The system also includes a WDP circuit module disposed within the housing. The WDP circuit module electrically coupleable with the wired drill pipe section. The system includes a further circuit module, disposed within the housing, which is electrically coupled with the WDP circuit module and electrically coupleable with the communication source/destination.

PRIORITY CLAIMS AND RELATED APPLICATIONS 
     The present Application claims priority from U.S. Provisional Patent Application No. 60/705,326, filed Aug. 4, 2005, and also claims priority from U.S. Provisional Patent Application No. 60/708,561, filed Aug. 16, 2005, and both said U.S. Provisional Patent Applications are incorporated herein by reference. Also the present Application contains subject matter that relates to subject matter disclosed in copending U.S. patent application Ser. No. 11/498,845 and copending U.S. patent application Ser. No. 11/498,847. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to telemetry systems for use in wellbore operations. More particularly, the present invention relates to wellbore telemetry systems for passing signals between a surface processor unit and a downhole tool positionable in a wellbore penetrating a subterranean formation. 
     BACKGROUND OF THE INVENTION 
     Wellbores are drilled to locate and produce hydrocarbons. A downhole drilling tool with a bit at one end thereof is advanced into the ground via a drill string to form a wellbore. The drill string and the downhole tool are typically made of a series of drill pipes threadably connected together to form a long tube with the bit at the lower end thereof. As the drilling tool is advanced, a drilling mud is pumped from a surface mud pit, through the drill string and the drilling tool and out the drill bit to cool the drilling tool and carry away cuttings. The fluid exits the drill bit and flows back up to the surface for recirculation through the tool. The drilling mud is also used to form a mudcake to line the wellbore. 
     During the drilling operation, it is desirable to provide communication between the surface and the downhole tool. Wellbore telemetry devices are typically used to allow, for example, power, command and/or communication signals to pass between a surface unit and the downhole tool. These signals are used to control and/or power the operation of the downhole tool and send downhole information to the surface. 
     Various wellbore telemetry systems may be used to establish the desired communication capabilities. Examples of such systems may include a wired drill pipe wellbore telemetry system as described in U.S. Pat. No. 6,641,434, an electromagnetic wellbore telemetry system as described in U.S. Pat. No. 5,624,051, an acoustic wellbore telemetry system as described in PCT Patent Application No. WO2004085796, the entire contents of which are hereby incorporated by reference. Other data conveyance or communication devices, such as transceivers coupled to sensors, may also be used to transmit power and/or data. 
     With wired drill pipe (“WDP”) telemetry systems, the drill pipes that form the drill string are provided with electronics capable of passing a signal between a surface unit and the downhole tool. As shown, for example, in U.S. Pat. No. 6,641,434, such wired drill pipe telemetry systems can be provided with wires and inductive couplings that form a communication chain that extends through the drill string. The wired drill pipe is then operatively connected to the downhole tool and a surface unit for communication therewith. The wired drill pipe system is adapted to pass data received from components in the downhole tool to the surface unit and commands generated by the surface unit to the downhole tool. Further documents relating to wired drill pipes and/or inductive couplers in a drill string are as follows: U.S. Pat. No. 4,126,848, U.S. Pat. No. 3,957,118 and U.S. Pat. No. 3,807,502, the publication “Four Different Systems Used for MWD,” W. J. McDonald, The Oil and Gas Journal, pages 115-124, Apr. 3, 1978, U.S. Pat. No. 4,605,268, Russian Federation Published Patent Application 2140527, filed Dec. 18, 1997, Russian Federation Published Patent Application 2,040,691, filed Feb. 14, 1992, WO Publication 90/14497A2, U.S. Pat. No. 5,052,941, U.S. Pat. No. 4,806,928, U.S. Pat. No. 4,901,069, U.S. Pat. No. 5,531,592, U.S. Pat. No. 5,278,550, and U.S. Pat. No. 5,971,072. 
     With the advent and expected growth of wired drill pipe technology, various types of circumstances will arise where it is necessary to connect a section of wired drill pipe to various types of uphole equipment or various types of tools or other downhole equipment. In some cases, the wired drill pipe may be incompatible with one or more components in the downhole tool and/or surface units. 
     It is, therefore, desirable to provide an interface to establish a communication link between a section of the wired drill pipe and the downhole tool and/or surface unit to facilitate communication between the downhole tool and a surface unit. It is further desirable to provide wellbore telemetry systems capable of providing added reliability, increased data rate, compatibility between a variety of downhole systems and increased power capabilities. Such a system is preferably capable of one or more of the following, among others: improving reliability, reducing communication failures, improving connectability, increase bandwidth, increase data rates, providing flexibility for a variety of downhole configurations and adapting wellbore telemetry tools to various wellsite configurations. 
     SUMMARY OF THE INVENTION 
     A form of the present invention has application for use in a drilling operation that includes uphole electronic equipment and a drill string suspended in an earth borehole, the drill string having at least one downhole tool thereon, the drill string also having a section of wired drill pipe that is part of a communication link between the downhole tool and the uphole electronic equipment. In accordance with an embodiment of the invention, an interface is provided for communicating between said section of wired drill pipe and a communication source/destination. [As defined herein, the communication source/destination can be any part of the communication link, between and including the uphole electronic equipment and the downhole tool. For example, without limitation, the communication source/destination can be the uphole electronic equipment or an uphole sub that is coupled with the uphole electronic equipment (in which case, the interface is sometimes referred to as an uphole interface), or the communication source/destination can be the downhole tool, a bottom hole assembly containing the dowhhole tool, or another section of WDP (in which case the interface is sometimes referred to as a downhole interface).] A housing is provided, the housing having a generally cylindrical outer shape and having a passage therethrough. The housing has a WDP end connectable to the section of wired drill pipe and a further end connectable to the communication source/destination. A WDP circuit module is disposed within the housing, the WDP circuit module being electrically coupleable with the wired drill pipe section. A further circuit module is also disposed within the housing, the further circuit module being electrically coupled with said WDP circuit module and electrically coupleable with the communication source/destination. 
     As previously noted, with the advent and expected growth of wired drill pipe technology, various types of circumstances will arise where it is necessary to connect a section of wired drill pipe to various types of uphole equipment or various types of tools or other downhole equipment. If and when usage of interfaces for wired drill pipe systems becomes more common, the number of different types of interfaces is expected to increase, by virtue of sections of WDP being connected to various types of uphole and downhole equipment. Accordingly, in the described embodiment of the present invention, interfaces are provided in an advantageous modular form. In this manner, it will be necessary to produce and stock less interfaces having specific pairs of endpoint characteristics. Also, modules can, if desired, be fabricated by different entities having particular expertise with regard to the module's electrical and mechanical composition as it relates, especially, to the external equipment to which the particular module's external end will ultimately be coupled. 
     Accordingly, in an embodiment of the invention, the WDP circuit module and the further circuit module are removably coupled, and the WDP circuit module and further circuit module are separately removable from the housing. In a form of this embodiment, the housing is comprised of two separable and connectable housing modules including a WDP housing module containing said WDP end of the housing and containing said WDP circuit module, and a further housing module containing said further end of the housing and containing said further circuit module. 
     In an embodiment of the invention, said further circuit module comprises a power source that provides power using an internal power module and/or a battery, and/or an external power source. 
     In an embodiment of the invention, at least one of said WDP circuit module and said further circuit module includes one or more of the following: a readout port, diagnostics circuitry, a controller, a real-time clock, and one or more sensors. 
     In an embodiment of the invention the passage in the housing comprises at least a partial central axial passage, and the WDP circuit module and further circuit module are mounted in the housing generally adjacent the central axial passage. In this embodiment, said further end includes a connector, electrically coupled with said further circuit module, for connection to the communication source/destination, said connector being axially within an annular passage that communicates with said partial central axial passage. Also in this embodiment, said connector further comprises an electronics module. 
     In a further embodiment of the invention, the passage in the housing comprises at least a partial annular passage, and one of said WDP circuit module and further circuit module are mounted in a central portion of the housing within said partial annular passage. 
     Further features and advantages of the invention will become more readily apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the above recited features and advantages of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof that are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
         FIG. 1  is a schematic view, partially in cross-section of wellsite having a downhole tool deployed from a rig and into a wellbore via a drill string having a wired drill pipe telemetry system therein. 
         FIG. 2A  is a schematic view of an embodiment of an uphole interface for passing signals between a surface unit and a wired drill pipe telemetry system. 
         FIG. 2B  is a schematic view of an embodiment of a downhole interface for passing signals between a surface unit and a wired drill pipe telemetry system. 
         FIG. 3  is a schematic view of an embodiment of a modem usable in the downhole interface of  FIGS. 2A and 2B . 
         FIGS. 4A-D  are schematic views of various configurations of interfaces used in combination with wired drill pipe telemetry systems and downhole tools. 
         FIGS. 5A and 5B  are cross-sectional views of embodiments of the interface of the invention. 
         FIGS. 6A and 6B  are cross-sectional views of modularized interfaces in accordance with embodiments of the invention. 
         FIGS. 6C and 6D  are cross-sectional views of interfaces in accordance with further embodiments of the invention. 
         FIGS. 7A-7C  are schematic diagrams, in block form, of the electronics used in embodiments of the interfaces of the invention. 
         FIGS. 8 and 9  show block diagrams of a controller and modem, respectively, used in embodiments of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Presently preferred embodiments of the invention are shown in the above-identified figures and described in detail below. In describing the preferred embodiments, like or identical reference numerals are used to identify common or similar elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness. 
       FIG. 1  illustrates a wellsite system  1  with which the present invention can be utilized to advantage. In the illustrated system, a borehole  11  is formed by rotary drilling in a manner that is well known. Those of ordinary skill in the art given the benefit of this disclosure will appreciate, however, that the present invention also finds application in drilling applications other than conventional rotary drilling (e.g., mud-motor based directional drilling and rotary steerable systems), and is not limited to land-based rigs. 
     The downhole system  3  includes a drill string  12  suspended within the borehole  11  with a drill bit  15  at its lower end. The surface system  2  includes the land-based platform and derrick assembly  10  positioned over the borehole  11  penetrating a subsurface formation F. The assembly  10  includes a rotary table  16 , kelly  17 , hook  18  and rotary swivel  19 . The drill string  12  is rotated by the rotary table  16 , energized by means not shown, which engages the kelly  17  at the upper end of the drill string. The drill string  12  is suspended from a hook  18 , attached to a traveling block (also not shown), through the kelly  17  and a rotary swivel  19  which permits rotation of the drill string relative to the hook. 
     The surface system further includes drilling fluid or mud  26  stored in a pit  27  formed at the well site. A pump  29  delivers the drilling fluid  26  to the interior of the drill string  12  via a port in the swivel  19 , inducing the drilling fluid to flow downwardly through the drill string  12  as indicated by the directional arrow  9 . The drilling fluid exits the drill string  12  via ports in the drill bit  15 , and then circulates upwardly through the region between the outside of the drill string and the wall of the borehole, called the annulus, as indicated by the directional arrows  32 . In this manner, the drilling fluid lubricates the drill bit  15  and carries formation cuttings up to the surface as it is returned to the pit  27  for recirculation. 
     Below the drill string  12 , there is a bottom hole assembly (BHA), generally referred to as  100 , near the drill bit  15  (in other words, within several drill collar lengths from the drill bit). The bottom hole assembly includes capabilities for measuring, processing, and storing information, as well as communicating with the surface. The BHA  100  thus includes, among other things, an apparatus  110  for determining and communicating one or more properties of the formation F surrounding borehole  11 , such as formation resistivity (or conductivity), natural radiation, density (gamma ray or neutron), and pore pressure. 
     The BHA  100  further includes drill collar  150  for performing various other measurement functions. Drill collar  150  houses a measurement-while-drilling (MWD) tool. The MWD tool further includes an apparatus (not shown) for generating electrical power to the downhole system. While a mud pulse system is depicted with a generator powered by the flow of the drilling fluid  26  that flows through the drill string  12  and the MWD drill collar  150 , other power and/or battery systems may be employed. 
     Sensors may be provided about the wellsite to collect data, preferably in real time concerning the operation of the wellsite, as well as conditions at the wellsite. For example, such surface sensors may be provided to measure standpipe pressure, hookload, depth, surface torque, rotary rpm, among others. Downhole sensors may be disposed about the drilling tool and/or wellbore to provide information about downhole conditions, such as wellbore pressure, weight on bit, torque on bit, direction, inclination, drill collar rpm, tool temperature, annular temperature and toolface, among others. The information collected by the sensors are conveyed to the surface system, the downhole system and/or the surface control unit. 
     As shown in  FIG. 1 , an uphole interface  120  is provided at the uphole end of the drill string  12 , a downhole interface is provided at the downhole end of the drill string  12 . A wired drill pipe telemetry system  145  extends through the drill string  12 . A communication link  130  is schematically depicted between the uphole interface and the surface unit  4 . This configuration provides a communication link from the surface telemetry unit  4 , through communication link  130 , to uphole interface  120 , through the wired drill pipe telemetry system, to interface  140  and to downhole tool (or BHA)  100 . 
     While only one surface unit  4  at one wellsite  1  is shown, one or more surface units across one or more wellsites may be provided. The surface units may be linked to one or more surface interface using a wired or wireless connection via one or more communication lines  130 . The communication topology between the surface interface and the surface system can be point-to-point, point-to-multipoint or multipoint-to-point. The wired connection includes the use of any type of cables (wires using any type of protocols (serial, Ethernet, etc.) and optical fibers. The wireless technology can be any kind of standard wireless communication technology, such as IEEE 802.11 specification, Bluetooth, zigbee or any non-standard RF or optical communication technology using any kid of modulation scheme, such as FM, AM, PM, FSK, QAM, DMT, OFDM, etc. in combination with any kind of data multiplexing technologies such as TDMA, FDMA, CDMA, etc. As one example, the antenna for the wireless connection can be put in the outer layer of the sub. 
     As shown in  FIG. 1 , the uphole interface is positioned at the uphole end of the wired drill pipe telemetry system. The uphole interface operatively connects the wired drill pipe telemetry system to the surface unit. As shown, a communication link is provided between the uphole interface and the surface unit. Optionally, in cases where the drill pipe extends above the rotary table and to the top drive, the interface sub may, for example, be positioned between the top drive and the wired drill pipe. 
     The uphole interface  120  is shown in greater detail in  FIG. 2A . The uphole interface is provided with a surface modem  200 , a WDP uphole modem  202 , sensors  204  and a power module  206 . Typically, the uphole interface is housed in a drill pipe connectable to the uphole end of the drill string. 
     A WDP connector  208  is provided to operatively link the uphole interface with the wired drill pipe telemetry system. The connector may be an inductive coupler similar to the ones used on adjacent drill pipe in the WDP telemetry system. Alternatively, the connector may be a conductive connector or any other connector capable of communicating with the wired drill pipe telemetry system. 
     A surface connector  210  is also provided to operatively link the uphole interface with the surface unit. The surface connector may be a wired, wireless or optical connector adapted to link to the surface unit. The connector may provide for conductive, inductive, wired, wireless and/or optical communication with the surface unit. 
     One or more sensors  204  may be provided in the uphole interface  120  to measure various wellbore parameters, such as temperature, pressure (standpipe, mud telemetry, etc.), mud flow, noise, drilling mechanics (i.e., torque, weight on bit, acceleration, pipe rotation, etc.), etc. The measurements for drilling mechanics are performed at high sampling rates (typically 120 Hz). In addition, the pressure measurements are performed at higher sampling rates (typically 480 Hz) to facilitate telemetry demodulation. The sensors may be linked to an analog front end for signal conditioning and/or to a processor for processing and/or analyzing data. The sensors may also be used to perform diagnostics to locate faults in the wired drill pipe system, measure noise and/or characteristics of the wired drill pipe telemetry system and perform other diagnostics of the wellsite. The sensors may be integrated into the uphole interface  120  or placed along its outer diameter or inner diameter. Sensor data may be recorded in a memory device. 
     The uphole interface  120  may further be provided with a power module  206 . The power module may generate power using any kind of power generator such as a turbine, piezoelectric, solar cell, etc., from any kind of potential energy source such as mud flow, rotation, vibration, RF signal, etc. The uphole interface may also be powered using batteries alone or as a backup of a power generator technique. The batteries may be rechargeable. Alternative power may be provided externally and stored or used by the uphole interface. In the wired drill pipe system, the uphole interface  120  may also be powered using a cable from a power generator located on or near the rig. 
     The surface modem  200  is adapted to communicate with one or more modems in the surface unit  4 . The WDP uphole modem  202  is adapted to communicate with one or more modems, repeaters, or other interfaces in the downhole tool via the wired drill pipe telemetry system. Preferably, the modems provide bi-directional communications. Any kind of digital and analog modulation scheme may be used, such as biphase, frequency shift keying (FSK), quadrature phase shift-keying (QPSK), Quadrature Amplitude Modulation (QAM), discrete multi tone (DMT), etc. These schemes may be used in combination with any kind of data multiplexing technologies such as Time Division Multiplexing (TDM), Frequency Division Multiplexing (FDM), etc. The modem may include functionality for drill pipe diagnostics and downhole tool diagnostics. 
     The surface modem  200  is shown in greater detail in  FIG. 3 . The modem may be analog or digital. The modem includes a transmitter  300 , a receiver  302 , a processor  304  and a memory unit  306 . The transmitter and receiver may be in the form of an analog or digital transceiver. The transmitter is provided to transmit data received by the receiver from the downhole unit to the surface unit. The transmitter may also be used to transmit commands received from the surface unit by the receiver to the downhole tool. Diagnostic signals may also be transmitted from the interface sub to the downhole tool and/or surface unit. For diagnostics, signals from the downhole tools/surface units can be looped back to the downhole tools/surface units, respectively. 
     The processor  304  of the modem is used to modulate and demodulate signals received from the downhole tool and/or surface unit for conversion so that they may be received by the downhole tool and surface unit. Error corrections, detection, compression, encryption and other data manipulation may be performed. The modulation scheme for the interface is preferably set at a baud rate capable of communicating between the surface unit and the downhole tool. The baud rates of corresponding modems for the surface unit and interface are provided with aligned baud rates. Similarly, the baud rates of the corresponding modems for the downhole tool and the uphole interface are aligned. 
     The memory unit  306  is provided to store data for future use. Sensor or diagnostic data, for example, may be stored. 
     Other items, such as a global positioning system  308 , may also be provided to perform additional functions, such as setting a real time clock, or for time synchronization between uphole surface and downhole tools/surface units. Additionally, an analog front end (amplifiers, filters, etc.) may also be required. 
     Referring now to  FIG. 2B , a downhole interface  140  is depicted. The downhole interface is positioned between the WDP telemetry system and the downhole tool for communication therebetween. In some cases, a separate downhole interface may not be necessary, where the downhole tool is provided with an internal interface. Such an internal interface is made up of existing modems, processors, sensors and other features in the current downhole tool. 
     The downhole interface  140  may be the same as the uphole interface, except that the downhole interface is provided with a WDP downhole modem  320 , a downhole modem  322 , a WDP connector  324  and a downhole tool connector  326 . The downhole interface provides a communication link between the uphole interface and the downhole interface. The downhole modem provides a communication link between the WDP telemetry system and one or more components in the downhole tool. Additionally, a downhole connector  326  will be provided in place of the surface connector. The downhole connector may be wired or wireless and provide an inductive, conductive or optical connection between the WDP telemetry and the downhole tool. The WDP connector  324  operatively connects the downhole interface to the wired drill pipe telemetry system. 
     Communication between the interface(s) and the downhole tool and/or surface unit is performed according to a protocol. The protocol defines the format and sequence for signals that are sent and received by the interface. The protocol may be, for example, a predefined set of rules that establish the communication scheme between corresponding modems. The protocol may be selectively adjusted to conform to the requirements of a given telemetry system. Alternatively, a given telemetry system may be adapted to conform to the protocol of the interface. The protocol and/or baud rates for the downhole interface may be adjusted to the uphole interface, and the protocol and/or baud rates for the uphole interface may also be adjusted to the downhole interface. 
       FIG. 4  schematically depicts a variety of possible configurations utilizing one or more interfaces. The interfaces may be positioned at a variety of locations along the wellsite. For example, one of the uphole interface may be positioned adjacent the top drive, and another located further downhole. In another example, one downhole interface may be positioned adjacent the wired drill pipe telemetry system, and another interface positioned further downhole along the downhole tool. 
       FIG. 4A  shows a wired drill pipe telemetry system  445  directly connected to a downhole tool  410 . An uphole interface  422  is positioned above the wired drill pipe telemetry system. A downhole interface  440  is integral to the downhole tool  410 . In this situation, the downhole interface may be formed from existing portions of the downhole tool, such as processors, modems and other devices that form portions of the components of the downhole tool. 
       FIG. 4B  depicts multiple wired drill pipe telemetry systems  445 , each having its own downhole interface  450 . An uphole interface  422  is provided at an uphole end of the upper most wired drill pipe telemetry system. The downhole interfaces  450  can communicate simultaneously or independently with the downhole tool  410 . 
       FIG. 4C  depicts multiple downhole tools, each having its own downhole interface  450 . An uphole interface  422  is provided at an uphole end of the wired drill pipe telemetry system.  FIG. 4D  depicts a wired drill pipe telemetry system having multiple uphole interfaces  422  and multiple downhole interfaces  450 . 
       FIG. 5A  depicts an example of an interface  500  for use between a wired drill pipe system, such as the wired drill pipe system  145  of  FIG. 1  and a downhole tool or bottom hole assembly, such as the BHA  100  of  FIG. 1 . The interface  500  includes a housing  502 , a WDP connector  524 , a downhole connector  526  and electronics  550 . As shown, the electronics are positioned on an inner surface of the drill collar to permit the flow of mud therethrough as indicated by the arrows. The electronics are preferably removably loaded into the drill collar and mounted against a shoulder  527 . 
     The housing may be a drill collar or other tubing or sub connectable to the WDP system and/or downhole tool. Alternatively, the housing may be part of the WDP system and/or downhole tool. Preferably the ends  531  and  533  are threadably connected to corresponding drill pipes of the WDP system and/or downhole tool. As shown, ends  531  and  533  are box ends provided with mating internal threads adapted to threadably engage an adjacent drill pipe for operative connection therewith. The ends may optionally be box or pin ends as necessary to mate with adjacent collars. One or more such interface  500  may be connected together or separated by additional drill collars. The interface may be inverted, so long as the operative connections are mated to their respective tools. 
     The WDP connector  524  and the downhole connector  526  operatively connect the interface to the WDP system and the downhole tool, respectively. The electronics  550  are used to pass signals between the WDP system and the downhole tool. The electronics contain a WDP modem  520  and a downhole modem  522 . Additional electronics may also be included, such as the electronics shown in  FIGS. 2A, 2B and 3 .  FIGS. 7A-9  illustrate additional configurations for the electronics as will be described further below. 
     As shown in  FIG. 5A , additional features, such as a read out port  525  may also be provided. The read out port provides access to the electronics. For example, when the tool is retrieved to the surface, a surface unit may be plugged into the readout port to retrieve data, insert commands, terminate power or perform other procedures. 
       FIG. 5B  depicts an interface  500   a  with a partially annular and partially mandrel style configuration. Interface  500   a  is essentially the same as  FIG. 5A , except that a portion of the electronics is positioned in a mandrel layout. In other words, a portion of the electronics  550   a  are positioned along the inner surface of housing  502  as shown in  FIG. 5A , and another portion of the electronics  550   b  are positioned in a mandrel configuration within the housing. Centralizers  552  are positioned along the inner surface of the housing to support the electronics  550   b , and have apertures therethrough to permit the passage of drilling mud as indicated by the arrows. 
       FIGS. 6A-D  depict various configurations of a modular interface for use between a wired drill pipe system, such as the wired drill pipe system  145  of  FIG. 1  and a downhole tool or bottom hole assembly, such as the BHA  100  of  FIG. 1 . As shown in  FIG. 6A , the modular interface  600  includes a housing  602 , a WDP connector  624 , downhole connectors  626   a ,  626   b , and electronics  650   a ,  650   b . As shown, the electronics are positioned on an inner surface of the drill collar to permit the flow of mud therethrough as indicated by the arrows. The electronics are preferably removably loaded into the drill collar and mounted on along an inner surface thereof. 
     The housing may be the same as in  FIG. 5A . As shown in  FIG. 6A , uphole end  631  is a box end, and downhole end  633  is a pin end with threadable connections for operatively connecting to their respective tools. 
     The housing may be provided with one or more connections  660 . The connections  660  provide modularity for the interface  600 . Portions of the interface may be selectively connected or separated. The connections may be for example, shop joint, threaded, soldered, welded, or other joints that operatively connect portions of the interface. The connections permit separation of the interface as necessary, for example for maintenance or machining. For example, where a WDP system is developed by a first entity, the first entity may develop a WDP portion of the related interface, and where the downhole tool is developed by a second entity, that second entity may develop the downhole portion of the interface. In this manner, the interface may be separately manufactured and then jointly assembled. Electronics  650   a ,  650   b  are preferably positioned in separate modules to permit separate assembly. While two sets of electronics are depicted, additional modules with additional electronics may be provided. 
     One or more connectors, such as link  662 , may be used to operatively connect the electronics  650   a  and  650   b . Links  670   a  and  670   b  are provided to operatively connect the electronics  650   a  to WDP connector  624  and electronics  650   b  to downhole connector  626   b , respectively. The connections, links, read out ports or other devices may communicate via wired, wireless, or any type of connector that permits an operative connection. Where such connections extend across a connection  660 , an additional joint may be used. 
     The WDP connector  624  and the downhole connector  626   a  may be the same as the connectors  524 ,  526 , respectively. Optionally, an additional or alternative downhole connector  626   b  may be used, such as an inductive or conductive connector operatively connectable to the downhole tool. The electronics  650   a ,  650   b  are used to pass signals between the WDP system and the downhole tool. The electronics  650   a  and  650   b  are depicted as having a WDP modem  620  and a downhole modem  622 , respectively to enable communication therethrough. Connectors, such as  624 ,  626   a  and  626   b  may be positioned at various locations within the interface, so long as an operative connection is provided. 
     Additional electronics may also be included, such as the electronics shown in  FIGS. 2A, 2B and 3 .  FIGS. 7A-9  describe additional configurations for the electronics as will be described further below. As shown in  FIG. 6A , read out ports  625   a, b  may also be provided with read out circuitry positioned therein. For example, such read out circuitry may include sensors and other electronics, such as those shown in  FIGS. 7A-9  and described further herein. The read out ports  625   a ,  625   b  may be the same as the read out port  525  of  FIG. 5A , except that circuitry may be provided therein to facilitate connections and signal transfers. 
     As shown in  FIG. 6A , one or more additional components  672  may be positioned in the interface to perform a variety of additional functions. For example, the component may be used to perform a variety of downhole operations, such as downhole sensing (ie. pressure), power generation, telemetry, memory or other operations. 
       FIG. 6B  shows an alternate configuration of a modular interface  600   a  is the same as the modular interface  600   a  of  FIG. 6A , except that additional electronics  650   c  and  650   d  are provided. As shown electronics  650   c  are additional electronics positioned in an annular position along the inner surface of the housing  602  adjacent the electronics  650   a . Electronics  650   d  are supported on centralizers  652  in a mandrel position within the housing. In this configuration, the modular connection may be separate along connection  660  such that a first portion of the interface contains electronics  650   a  and  650   c , and a second portion contains electronics  650   b  and  650   d . Additional connections  660  may be provided to permit additional separations, for example for threaded end  631  with coupler  624  and threaded end  633  with downhole connector  626   b.    
       FIG. 6C  shows an alternate modular interface  600   b . In this configuration, electronics  650   a  are positioned along the inner surface, and electronics  650   e  is positioned on an inner surface of the housing adjacent electronics  650   a . Electronics  650   a  is provided with WDP modem  620 , and electronics  650   e  is provided with downhole modem  622 . Preferably, electronics  650   e  are removably positioned within the drill collar. In this manner, the electronics  650   e  may be separated from the interface for separate maintenance, installation, etc. 
     As shown in  FIG. 6C , the housing has a first box end  631 , and a pin end  633   a . As described above, the ends may be box and/or pin or other connections capable of operatively connecting the interface with the drill string and/or downhole tool. 
       FIG. 6D  shows an alternate modular interface  600   c . The modular interface  600   c  may be the same as the modular interface  600   b  of  FIG. 6C , except that the electronics  650   e  is replaced with electronics  650   f  in a mandrel configuration. Downhole modem  622  is positioned in electronics  650   f  for communication with the downhole tool. 
     Centralizers  652   a ,  652   b  are provided to support the electronics  650   f  in the housing. Centralizer  652   a  may be, for example, supports positioned about the electronics. Centralizer  652   b  may be, for example, a ring or spider used to support the electronics. 
     While the configurations shown in  FIGS. 5A-6D  depict specific arrangements of electronics, connectors and other devices within a housing, it will be appreciated that these arrangements may be varied. For example, WDP connectors and modems may be positioned in various locations about the housing. 
       FIGS. 7A-C  are schematic diagrams depicting a detailed view of the electronics  750  usable with the interfaces provided herein. As shown, the electronics include a WDP modem  720 , a downhole modem  722  and power module  781 . As shown, power may be provided internally using power module  781  and/or battery  771  and/or external power source  772 . Additional electronics may also be provided, such as diagnostics  773 , controller  774 , sensors  775 , GPS/real time clock  776  and read out port (ROP)  725 . 
     The controller may be used for processing signals, analyzing data, controlling the power supply and performing other downhole operations. The diagnostics may be used for monitoring the electronics, the downhole tool, the WDP system and other related systems. The sensors may be the same as the sensors  204  of  FIG. 2B . The GPS/real time clock may be used, for example, to provide a time stamp for the data acquired from the sensor and time synchronization. The read out port may be the same as the read out port  625  described herein. 
       FIG. 7B  depicts an alternate configuration for the electronics  750   a . In this configuration, the electronics  750  of  FIG. 7A  are separated into a WDP portion  782 , and a downhole portion  780  with a connector  762  therebetween. As shown, the electronics  780  are the same as the electronics  750  of  FIG. 7A , except that the WDP modem  720  has been moved to the WDP portion  782 , and a signal/power interface  778  is provided to operatively communicate with the WDP portion  782 . 
     The WDP portion  782  is provided with the WDP modem  720  and a signal/power interface  778   b  that communicates with signal power interface  778   a  of the downhole portion  780 . Connector  762  is optionally provided to operatively connect the upper and lower portions. In some cases, this may be a field joint or other type of connector capable of passing signals between the portions  780 ,  782 . The connection may be, for example, inductive, conductive or optical and wired or wireless. 
       FIG. 7C  depicts another configuration of electronics  750   b . This configuration is the same as the electronics  750   a  of  FIG. 7B , except that the WDP portion  782   a  is provided with additional electronics. The WDP portion  782   a  contains the WDP modem  720  and the signal power interface  778   b  (as with previous WDP portion  782  of  FIG. 7B ), plus power module  781 , battery  771 , GPS/real time clock  776 , ROP  725 , sensors  775 , controller  774 , diagnostics  773  an external power  772 . This configuration shows that a variety of electronics may be used with the one or more portions of the electronics. While two portions are depicted, multiple portions containing various portions of the electronics may be provided. Connectors may be needed to join the respective electronics. 
       FIGS. 8 and 9  show an alternate configuration of the surface modem  200  of  FIG. 3 , split into separate portions.  FIG. 8  is a detailed view of a controller  774 . The controller may be provided with a processor  892 , memory  894 , Application Specific Integrated Circuit (ASIC)/Field Programmable Device (FPD)  893  and other circuitry. 
       FIG. 9  is a detailed view of downhole modem  772 . The same configuration may be used for WDP modem  720 . The modem may include, for example, a transmitter and receiver (or transceiver)  995 . In cases where analog is used, the modem may also be provided with a filter  996 , an amplifier  997 , a gain control  998 , a modulator  999 , a demodulator  989  and a data converter  988 . 
     The interfaces as shown in  FIGS. 5A-6D  may be positioned about a WDP system and/or downhole tool as shown in  FIGS. 4A-4D . For example, the interfaces of  FIGS. 5A-6D  may be configured as surface interfaces, such as the interfaces  422  of  FIGS. 4A-4D , integral interface  440  of  FIG. 4A  and/or downhole interfaces  450  of  FIGS. 4B-4D . The interfaces as described herein may also be provided with one or more repeaters to amplify and/or reshape the signal. Repeaters and other devices, such as the modem depicted in  FIG. 9 , may be used to improve the signal as it is passed through the wellbore. 
     These configurations allow, among other things, flexibility in adapting to a variety of downhole tools and wired drill pipe telemetry systems. In addition to the figure depicted, various combinations of integral and separate interfaces may be used. Multiple integral interfaces may also be used. 
     It will be understood from the foregoing description that various modifications and changes may be made in the preferred and alternative embodiments of the present invention without departing from its true spirit. For example, the communication links described herein may be wired or wireless. The devices included herein may be manually and/or automatically activated to perform the desired operation. The activation may be performed as desired and/or based on data generated, conditions detected and/or analysis of results from downhole operations. 
     This description is intended for purposes of illustration only and should not be construed in a limiting sense. The scope of this invention should be determined only by the language of the claims that follow. The term “comprising” within the claims is intended to mean “including at least” such that the recited listing of elements in a claim are an open group. “A,” “an” and other singular terms are intended to include the plural forms thereof unless specifically excluded.