Patent Publication Number: US-6217380-B1

Title: Connector for different sized coaxial cables and related methods

Description:
FIELD OF THE INVENTION 
     The present invention relates to the field of cables and connectors, and, more particularly, to a connector and associated method for joining together different sized coaxial cables, as may be particularly advantageous in a wireless base station. 
     BACKGROUND OF THE INVENTION 
     Coaxial cables are widely used to carry high frequency electrical signals. Coaxial cables enjoy a relatively high bandwidth, low signal losses, are mechanically robust, and are relatively low cost. One particularly advantageous use of a coaxial cable is for connecting electronics at a cellular or wireless base station to an antenna mounted at the top of a nearby antenna tower. For example, the transmitter located in an equipment shelter may be connected to a transmit antenna supported by the antenna tower. Similarly, the receiver is also connected to its associated receiver antenna by a coaxial cable path. 
     A typical installation includes a relatively large diameter cable extending between the equipment shelter and the top of the antenna tower to thereby reduce signal losses. For example, CommScope, Inc. of Hickory, N.C. and the assignee of the present invention offers its CellReach® coaxial cable for such applications. The cable includes a smooth wall outer conductor which provides superior performance to other cable types. The smooth outer wall construction also provides additional ease of attaching connector portions to the cable ends in comparison to other coaxial cable types, such as including corrugated outer conductors, for example. 
     Each end of the large diameter coaxial cable is connected to a respective smaller diameter, and relatively short, jumper cable. The jumper coaxial cable has a smaller diameter with greater flexibility to thereby facilitate routing at the equipment shelter and also at the top of the antenna tower. More particularly, a relatively large diameter (about 1 and ⅝ inch) main coaxial cable extends from the shelter to the top of the tower, typically about 90 to 300 feet, to reduce attenuation. The main cable may be a CellReach® model 1873 cable, for example. A short smaller diameter (about ½ inch) coaxial jumper cable is connected to each end of the main cable, and may be a CellReach® model 540 cable, for example. The top jumper is typically 3 to 6 feet long, and the bottom jumper is typically 6 to 10 feet long. 
     At present, and as understood with reference to the prior art arrangement shown in FIGS. 2 and 3, first and second connectors  33 ,  34  are typically assembled in a back-to-back relation to couple an end of the main coaxial cable  31  to an end of a jumper coaxial cable  32 . The first connector  33  includes a first back-nut assembly  35  and a first body portion  36  which are threadingly engaged together. A rear  0 -ring, not shown, may seal the cable sheath  54  to the first back-nut assembly  35 . Similarly, the second connector  34  includes a second back-nut assembly  41  which threadingly engages a second connector body portion  42 . As shown in the illustrated prior art connector arrangement  30 , the first or main cable  31  includes an elongate central strength member  43 , a surrounding dielectric layer  45 , and a surrounding adhesive layer  46  for attachment to the tubular copper center conductor  47 . A tubular dielectric layer  48  surrounds the center conductor  47 . In the illustrated embodiment, a portion of the dielectric layer  48  has been removed by a coring tool to thereby facilitate assembly. A tubular plastic body  51  is inserted into the cored cable end. 
     A portion of the outer smooth wall conductor  53  is exposed beyond the end of the cable sheath  54 . A metal clamping ring  56  is urged against the exposed outer conductor  53  as the back-nut outer cylinder  55  is threaded onto the connector body portion  36 . The connector body portion  36  includes a hollow metal member  57  in which is positioned an annular dielectric spacer  61 , which, in turn, supports a center contact  62 . The center contact  62  includes a tubular proximal end which receives and establishes contact with the inner conductor  47 . An annular dielectric body  63  provides a radially compressive force to the tubular end  63  of the center contact  62  as the back-nut  35  and connector body portion  36  are threadingly engaged. A rubber  0 -ring  67  seals the interface between the first back-nut assembly  35  and the connector body portion  36 . A distal end  65  of the center contact  62  is centered within a hollow tubular distal end  66  of the hollow metal member  57 . The distal end  66  includes threads on its outer surface to mate with the second connector body portion  42 . Another  0 -ring  94  is positioned at the distal end  66  for sealing the interface with the hollow metal member  85 . 
     Turning now to the right-hand portion of FIG. 3, the second connector  34  is briefly described. The second connector  34  includes a second back-nut assembly  41  which is connected to the end of the second or jumper cable  32 . The second cable  32  includes a central metallic conductor  71 , surrounded by a dielectric layer  73 , a portion of which is removed to prepare the cable end. A plastic insert  74  is positioned within the cable end to support the outer conductor  75 . A cylindrical member  77  is secured on the cable end and clamps to an exposed portion of the outer conductor  75  which extends outwardly beyond the end of the cable sheath  76 . Additional metal rings  81 ,  82  and  83  cooperate with the second connector body portion  42  and cylinder  77  to provide the necessary clamping action on the outer conductor  75  and also on the inner conductor  71 . A rear  0 -ring, not shown, may seal the cable sheath  76  to the second back-nut assembly  41 . 
     The second connector body portion  42  includes a hollow metal member  85  which mounts an annular dielectric spacer  86  and which, in turn, carries a center contact  87 . The center contact  87  includes a tubular distal end  88  which receives and is clamped against the inner conductor  71  by the annular dielectric body  90 . An  0 -ring  91  seals the interface between the second connector body portion  42  and the second back-nut assembly  41 . A collar  92  including internal threads on its distal end is rotatably connected at its proximal end to a recess in the distal end of the hollow metal member  85 . The collar  92  secures the first connector  33  to the second connector  34 . The distal end  93  of the center contact  87  engages the distal end  65  of the center contact  62  in the region of the collar  92 . 
     As will readily be appreciated, the back-to-back connector arrangement  30  includes a relatively large number of component parts which is relatively expensive and may be difficult to assemble. Such an arrangement  30  will also typically have more loss per unit length than the coaxial cable. Such a back-to-back connector arrangement  30  can be unreliable, and presents multiple interfaces for water leakage into the cable. The connector arrangement  30  also presents a number of abrupt edge surfaces which may make routing through restricted openings difficult, such as at the tower entry and exit ports, or at collars at spaced heights within a monopole tower. 
     A number of patents disclose other arrangements of connectors for securing a larger diameter coaxial cable to a smaller diameter coaxial cable. For example, U.S. Pat. No. 4,853,656 to Guilou et al. discloses such a device. The device comprises a central core in the shape of a truncated cone, whose circular bases have sections respectively identical to those of the central cores of the coaxal cables to be connected together, as well as a peripheral sheath, whose internal wall is a truncated cone shaped surface, whose circular bases have sections respectively identical to the internal sections of the peripheral sheaths of the coaxial cables. The small bases of the truncated cones of the central core and the peripheral sheath are two parallels of a first sphere centered on the apex of the truncated cone surface of the internal wall. The large bases of the truncated cones of the central core and of the peripheral sheath are two parallels of a second sphere concentric with the first one. This arrangement is disclosed for enhancing the propagation of electromagnetic waves through the device. Unfortunately, this device is also relatively complicated and difficult to assemble. In addition, a number of threaded interfaces are present which may permit water to enter the device and thereby reduce its reliability. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing background, it is therefore an object of the present invention to provide a reliable and easy to assembly connector and associated method for joining together two coaxial cables having different diameters, as may commonly be used in a wireless base station, for example. 
     This and other objects, features and advantages in accordance with the present invention are provided by a coaxial cable connector for joining together a first coaxial cable having a first diameter and a second coaxial cable having a second diameter smaller than the first diameter, and comprising a hollow connector body for joining first and second back-nut assemblies together. Each coaxial cable has an inner conductor, a dielectric region surrounding the inner conductor, and an outer conductor surrounding the dielectric region. The first back-nut assembly preferably comprises a threaded distal end, and outer conductor clamping portions for coupling to the outer conductor of the first coaxial cable. Similarly, the second back-nut assembly preferably comprises a threaded distal end, and outer conductor clamping portions for coupling to the outer conductor of the second coaxial cable. 
     The hollow connector body preferably includes opposing first and second threaded ends to be threadingly engaged in the respective distal threaded ends of the first and second back-nut assemblies, AND an intermediate portion having a frusto-conical shape with a larger diameter portion adjacent the first end and a smaller diameter portion adjacent the second end. In addition, the connector also preferably includes a dielectric spacer positioned within a medial portion of the hollow connector body. A center contact is preferably positioned within an opening of the dielectric spacer. The center contact may have opposing ends for coupling to the respective inner conductors of the first and second coaxial cables. 
     The first and second threaded ends, and the intermediate portion of the hollow connector body are preferably integrally formed so that the hollow connector body is a monolithic unit. Accordingly, the connector is relatively straightforward to assemble and is reliable in service. First and second sealing rings may be provided for forming respective first and second seals between the first and second back-nut assemblies and the hollow connector body. Accordingly, resistance to moisture penetration is further enhanced. Each of the distal threaded ends of the first and second back-nut assemblies may be internally threaded, and, thus, each of the first and second threaded ends of the hollow connector body maybe externally threaded. 
     The hollow connector body may comprise portions defining an internal cylindrical passageway with a shoulder adjacent the smaller diameter end. In this embodiment, the dielectric spacer is positioned in the internal cylindrical passageway and abuts the shoulder. 
     The first and second ends of the center contact may have a tubular shape for receiving therein the first and second inner conductors respectively. The first and second ends of the center contact may also have elongate slots therein. The connector may also include first and second dielectric clamping members for clamping the first and second tubular ends of the center contact onto the respective inner conductors of the first and second coaxial cables responsive to progressive tightening of the threaded engagement between the first and second threaded ends of the hollow connector body and the respective threaded distal ends of the first and second back-nut assemblies. 
     The hollow connector body may include a generally cylindrical intermediate portion with a series of gripping portions on a periphery thereof. These gripping portions may be flats or spanner holes to facilitate gripping during assembly. The hollow connector body may comprise brass with a silver plating thereon. 
     Another advantageous feature of the present invention is that the outer conductor of the first coaxial cable may be a smooth wall conductor, and the outer conductor clamping portions of the first back-nut assembly are configured to engage the smooth wall conductor of the first coaxial cable. Of course, both cables may have a smooth wall outer conductor. In addition, one or both of the coaxial cables may have a corrugated outer conductor. 
     A method aspect of the invention is for joining together a first coaxial cable having a first diameter and a second coaxial cable having a second diameter smaller than the first diameter. Each coaxial cable has an inner conductor, a dielectric region surrounding the inner conductor and an outer conductor surrounding the dielectric region. The method preferably comprises the steps of: attaching a first back-nut assembly on the first coaxial cable, the first back-nut assembly comprising a threaded distal end, and outer conductor clamping portions coupling to the outer conductor of the first coaxial cable; and attaching a second back-nut assembly on the second coaxial cable. The second back-nut assembly may comprise a threaded distal end, and outer conductor clamping portions coupling to the outer conductor of the second coaxial cable. 
     More particularly, the method also preferably includes the step of attaching the first and second back-nut assemblies together using a hollow connector body comprising opposing first and second threaded ends to be threadingly engaged in the respective distal threaded ends of the first and second back-nut assemblies, and an intermediate portion having a frusto-conical shape with a larger diameter portion adjacent the first end and a smaller diameter portion adjacent the second end. A dielectric spacer is preferably positioned within a medial portion of the hollow conductive body and has an opening extending therethrough. An elongate center contact is preferably positioned within the opening of the dielectric spacer and has opposing ends for coupling to the respective inner conductors of the first and second coaxial cables. The first and second ends and the intermediate portion of the hollow connector body are preferably integrally formed so that the hollow connector body is a monolithic unit. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic view of a wireless base station including a pair of connectors joining upper and lower jumper coaxial cables to a larger diameter main coaxial cable in accordance with the present invention. 
     FIG. 2 is an exploded side elevational view of a back-to-back connector arrangement, partially assembled, and as used for joining together a smaller diameter jumper coaxial cable to a larger diameter main coaxial cable as in the prior art. 
     FIG. 3 is a cross-sectional view of the back-to-back connector arrangement of the prior art as shown in FIG. 2, with the components fully assembled. 
     FIG. 4 is an exploded side elevational view of the connector, partially assembled, and as used for joining together a smaller diameter jumper coaxial cable to a larger diameter main coaxial cable in accordance with the present invention. 
     FIG. 5 is a cross-sectional view of the connector as shown in FIG. 4, with the components fully assembled. 
     FIG. 6 is an exploded perspective view of a portion of the connector in accordance with the present invention. 
     FIGS. 7 and 8 are greatly enlarged end views of opposing ends of the center contact of the connector arrangement as shown in FIG.  6 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout. 
     Referring initially to FIG. 1, one particularly advantageous application of the connector  130  of the invention in a cellular or wireless base station system  20  is described. Two connectors  130  are illustrated to connect the main coaxial cable  131  to the upper and lower jumper or smaller diameter coaxial cables  132 . As noted above in the Background of the Invention section, the main coaxial cable  131  may be a suitable length of CellReach® model 1873 cable, for example. The smaller diameter jumper coaxial cables  132  may be suitable lengths of CellReach® model 540 cable, for example. Both cables may have a smooth wall outer construction and are available from the assignee of the present invention, CommScope, Inc. of Hickory, N.C. The top jumper may typically be about 3 to 6 feet long, and the bottom jumper may typically be about 6 to 10 feet long. 
     As will be readily appreciated by those skilled in the art, other coaxial cable types and sizes may be used with the connector  130  of the present invention. Typical cable pairings using the CellReach® designations may be: jumper 540, main 1873; jumper 1070, main 1873; jumper 540, main 1070; and jumper 396, main 1070. In other words, the jumper cable may be about ¼ inch to 1 and ¼ inches in diameter, and the main cable may be from about 1 to 3 inches in diameter. 
     The lower jumper coaxial cable  132  is connected to the schematically illustrated radio  23 . In addition, at the upper end of the antenna tower  22 , the upper jumper cable  132  is connected to the antenna  25 . Each transmitter and receiver of a radio  23  is connected to such a coaxial cable system including the main cable  131 , jumper cables  132 , and connectors  130  as will be readily appreciated by those skilled in the art. Of course, a typical system  20  may include a plurality of radios  23 , and antennas  25 . Although the illustrated example of the cellular or wireless base station system  20  greatly benefits from the connector  130  in accordance with the invention, the connector can be used in many other applications as well. 
     In the illustrated embodiment, the radio  23  is positioned within an equipment shelter  21  as is typically located in proximity to the base of the antenna tower or monopole  22  as would be appreciated by those skilled in the art. The radio  23  may also be mounted in its own relatively compact environmental housing. As schematically illustrated, the interior of the antenna tower  22  may present one or more restricted openings such as defined by the vertically spaced apart collars  24 . A conventional back-to-back connector arrangement  30  (FIGS. 2 and 3) may be difficult to route past such obstructions because of the abrupt edge surfaces presented by such a connector arrangement. 
     Referring now additionally to FIGS. 4 through 8, the coaxial cable connector  130  of the invention is now described in greater detail. To simplify the description and highlight the invention, the first and second cables  131 ,  132  and their respective components are indicated with reference numerals incremented by  100  to correspond with the elements already described for the prior art connector arrangement  30  of FIGS. 2 and 3. Accordingly, these cable components need no further discussion herein. Similarly, the first and second back-nut assemblies  135 ,  141  are similar to those assemblies  35 ,  41  for the prior art connector arrangement  30  described above with reference to FIGS. 2 and 3. The components of the first and second back-nut assemblies  135 ,  141  are similar and are designated by reference numerals incremented by  100  over those corresponding components in FIGS. 2 and 3. The first and second back-nut assemblies  135 ,  141  are not further described in detail, so that the ensuing discussion can focus more particularly on the connector portion  200  of the connector  130 . 
     In particular, the connector portion  200  includes a hollow connector body  201  for joining together first and second back-nut assemblies  135 ,  141 . The first back-nut assembly  135  includes a distal end defining an internally threaded first nut, and outer conductor clamping portions  156 ,  151  for coupling to the outer conductor  153  of the end of the first coaxial cable  131 . Similarly, the second back-nut assembly  141  comprises a distal end portion defining an internally threaded second nut and outer conductor clamping portions  177 ,  181  and  174  for coupling to the outer conductor  175  of the end of second coaxial cable  132 . 
     The hollow connector body  201  includes opposing first and second ends  203 ,  204  each having external threads to be threadingly engaged in the Crespective first and second nuts. The connector body  201  also illustratively includes a first cylindrical intermediate portion  205  adjacent the first end  203 , and a second intermediate portion  206  having a frusto-conical shape with a larger diameter portion adjacent the first intermediate portion and a smaller diameter portion adjacent the second end  204 . 
     The connector portion  200  also includes an annular dielectric spacer  211  positioned within a medial portion of the hollow connector body  201 . An elongate center contact  212  is preferably positioned within the opening of the dielectric spacer  211 . The center contact  212  has opposing first and second ends  213 ,  214  for coupling to the respective inner conductors  147 ,  171  of the first and second coaxial cables  131 ,  132 . 
     As shown in the illustrated embodiment, the first and second ends  203 ,  204  and the first and second intermediate portions  205 ,  206  of the hollow connector body  201  are preferably integrally formed so that the hollow connector body is a monolithic unit. Accordingly, the connector  130  is relatively straightforward to assemble and is reliable in service. The connector  130  includes only three major portions to assemble as perhaps best shown in FIG.  4 . In addition, the connector  130  in accordance with the invention may use conventional back-nut assemblies  135 ,  141  to thereby facilitate compatibility for replacement of conventional back-to-back connector arrangements  30  as in the prior art (FIGS.  2  and  3 ). 
     The connector  130  of the invention may also include the illustrated first and second sealing rings  167 ,  191  for forming respective first and second seals between the first and second back-nut assemblies  135 ,  141  and the respective first and second ends  203 ,  204  of the hollow connector body  201  as will be readily appreciated by those skilled in the art. The resistance to moisture penetration is further enhanced by these  0 -rings  167 ,  191  and because the number of interface locations is reduced by one as compared to the prior art. Of course, the back-nut assemblies  135 ,  141  may also each include a respective rear  0 -ring seal, not shown, for sealing the interface with the cable sheath as will be readily appreciated by those skilled in the art. 
     As seen perhaps best in the cross-sectional view of FIG. 5, the hollow connector body  201  may include interior portions defining an internal cylindrical passageway  215  with a shoulder  216  adjacent the smaller diameter end  204 . In this illustrated embodiment, the dielectric spacer  211  is snugly positioned in the internal cylindrical passageway  215  and abuts the shoulder  216  to ease assembly and provide secure positioning of the spacer  211  and thus proper alignment of the center contact  212 . 
     As shown in FIGS. 7 and 8, the first and second ends  213 ,  214  of the center contact  212  may have a tubular shape for receiving therein the first and second inner conductors  147 ,  171  respectively. The first and second ends  213 ,  214  of the center contact  212  may also have respective elongate slots  221 ,  222  therein. These slots  221 ,  222  facilitate clamping radially downwardly onto the respective center conductors  147 ,  171  as will now be further explained. 
     The connector  130  also includes first and second dielectric clamping members  163 ,  190  for clamping the first and second tubular ends  213 ,  214  of the center contact  212  onto the respective inner conductors  147 ,  171  of the first and second coaxial cables  131 ,  132 . This clamping occurs responsive to progressive tightening of the threaded engagement between the first and second ends  203 ,  204  of the hollow connector body  201  and the respective first and second back-nut assemblies  135 ,  141  as will be readily appreciated by those skilled in the art. 
     The first intermediate portion of the hollow connector body may have a series of flats  223  (FIGS. 4 and 6) on a periphery thereof. These flats  223  facilitate gripping during assembly. In another embodiment, the gripping portions may be provided in the form of spanner holes around the periphery as will be readily appreciated by those skilled in the art. The hollow connector body  201  may comprise brass with a silver plating thereon; however, those of skill in the art will recognize that other electrically conductive and corrosion resistant materials may be used as well. In addition, the hollow connector body  201  may include a surface treatment rather than a plating, for example. 
     Another advantageous feature of the present invention is at least that the outer conductor  147  of the first coaxial cable  131  may be a smooth wall conductor. In this embodiment, the outer conductor clamping portions of the first back-nut assembly  135  are configured to engage the smooth wall conductor of the first coaxial cable. Both cables  131 ,  132  may have a smooth wall outer conductor, and the outer conductor clamping portions of the second back-nut assembly  141  may also be configured to cooperate with the smooth wall cable. The smooth wall outer conductor is generally stronger under tensile forces than a corrugated conductor, for example. 
     In other embodiments, one or both of the cables  131 ,  132  may have a corrugated outer conductor as will be readily appreciated by those skilled in the art. As will also be understood by those skilled in the art, the respective outer conductor clamping portions of the back-nut assemblies may be configured to cooperate with the corrugated outer conductors without requiring further discussion herein. For typical corrugated outer conductor back-nut assemblies, the threaded distal ends are typically external rather than internal as described above. Accordingly, in such an embodiment, the hollow connector body would include internally threaded first and second ends as will be readily understood by those skilled in the art. 
     A method aspect of the invention is for joining together a first coaxial cable  131  having a first diameter and a second coaxial cable  132  having a second diameter smaller than the first diameter. Each coaxial cable preferably has an inner conductor, a dielectric region surrounding the inner conductor and an outer conductor surrounding the dielectric region. The method preferably comprises the steps of: attaching a first back-nut assembly  135  on the first coaxial cable  131 , the first back-nut assembly comprising a threaded distal end, and outer conductor clamping portions for coupling to the outer conductor of the first coaxial cable; and attaching a second back-nut assembly  141  on the second coaxial cable  132 , the second back-nut assembly comprising a threaded distal end, and outer conductor clamping portions for coupling to the outer conductor of the second coaxial cable. 
     More particularly, the method also preferably includes the step of attaching the first and second back-nut assemblies  135 ,  141  together using a hollow connector body  201  comprising opposing first and second threaded ends to be threadingly engaged in the respective threaded distal ends of the first and second back-nut assemblies, and an intermediate portion  206  having a frusto-conical shape with a larger diameter portion adjacent the first end and a smaller diameter portion adjacent the second end. A dielectric spacer  211  is preferably positioned within a medial portion of the hollow conductive body  201  and has an opening extending therethrough. An elongate center contact  212  is preferably positioned within the opening of the dielectric spacer  211  and has opposing ends coupling to the respective inner conductors of the first and second coaxial cables. The first and second ends and the intermediate portion of the hollow connector body  201  are preferably integrally formed so that the hollow connector body is a monolithic unit. 
     One preferred assembly sequence for the first and second back-nut assemblies  135 ,  141  and hollow connector body  201  may include securing the first back-nut assembly onto the first cable, securing the hollow connector body  201  to the first back-nut assembly, positioning the second back-nut assembly on the second cable, and tightening the second back-nut assembly onto the hollow connector body. Of course other assembly sequences are also contemplated by the invention as will be appreciated by those skilled in the art. 
     The method may also preferably include the step of positioning first and second sealing rings  167 ,  191  for forming respective first and second seals between the first and second back-nut assemblies  135 ,  141  and the hollow connector body  201 . Each of the ends of the first and second back-nut assemblies is may be internally threaded, and each of the first and second threaded ends of the hollow connector body  201  may be externally threaded. 
     The first and second ends of the center  212  contact may have a tubular shape for receiving therein the first and second inner conductors respectively. The first and second ends of the center contact  212  may also have elongate slots therein. Accordingly, the method may further comprise the step of positioning first and second dielectric clamping members  163 ,  190  for clamping the first and second tubular ends of the center contact  212  onto the respective inner conductors of the first and second coaxial cables  131 ,  132  responsive to progressive tightening of the threaded engagement between the first and second ends of the monolithic hollow connector body  201  and the respective first and second back-nut assemblies. 
     The hollow connector body  201  preferably further comprises a cylindrical intermediate portion  205  between the intermediate portion  206  having a frusto-conical shape and the first end. The cylindrical intermediate portion  205  of the hollow connector body  201  also preferably has a series of gripping portions, such as flats  223 , on a periphery thereof. Accordingly, the method also preferably includes the step of gripping the cylindrical intermediate portion  205  using the gripping portions thereon. 
     The first back-nut assembly  135  may have a corresponding size to receive the first cable  131  having a diameter within a range of about 1 to 3 inches. The second back-nut assembly  141  may have a corresponding size to receive the second cable  132  having a diameter within a range of about ¼ inch to 1 and ¼ inches in diameter. In addition, at least the outer conductor of the first coaxial cable may be a smooth wall conductor, and the outer conductor clamping portions of the first back-nut assembly may be configured to engage the smooth wall conductor of the first coaxial cable. Of course, one or both of the cables may also have a corrugated outer conductor. 
     The connector  130  of the invention provides a number of significant advantages over the conventional back-to-back connector arrangement  30  of the prior art. For example, the connector  130  of the invention when used for a coaxial cable route for a wireless base station  20  as shown in FIG. 1 eliminates two connections, that is, it replaces six connections with four connections. The connector  130  provides a secure weather seal and eliminates the conventional N interface. The connector  130  has improved mechanical robustness, less interfaces to cause problems, and makes secondary weatherproofing easier. The connector  130  has reduced insertion loss versus conventional back-to-back connector arrangements  30 . The connector  130  can also be mixed and matched with conventional connector parts, such as the back-nut assemblies. In addition, the connector  130  is less expensive than conventional connector arrangements. The frusto-conical shape of the second intermediate portion  206  facilitates passage through openings or adjacent edges, such as may be found in a wireless base station system  20  (FIG.  1 ). In other words, the connector  130  of the invention presents a clean, streamlined outer shape in contrast to the prior art back-to-back connector arrangement  30 . 
     Many modifications and other embodiments of the invention will come to the mind of one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed, and that modifications and embodiments are intended to be included within the scope of the appended claims.