The present disclosure generally relates to coaxial cables, and, more particularly, to systems and method for manufacturing coaxial cables having a modified impedance.
Generally, two radios co-located on the same computer platform (for example, but not limited to, located within a laptop, notebook netbook, and/or a tablet computer system) may need high isolation to function optimally. In particular, the isolation between the two radios in the computer platform may be necessary to prevent each radio from interfering with the reception of the other radio. The isolation may be achieved through highly selective filters on the front-end of a radio transceiver and/or a high isolation between the two radios' antennas.
As more and more radios and antennas are integrated in a computer system, achieving a high isolation between closely spaced antennas may be increasingly difficult and, as a result, a more stringent filter requirement may be forced upon the wireless module. The performance of the front-end filter on the wireless module may be compromised due to cost and real estate constraints. Consequently, many radio co-existence issues in computer systems (such as, but not limited to, mobile computing systems such as laptops, notebooks, netbooks, tablets and the like) are caused by front-end saturation and/or strong out-of-bound (OOB) interference from other embedded radios operating at a nearby frequency band.
Additionally, excessive filtering may be required to reject spurious emission of transmission in order to obtain regulatory compliance in a computer system comprising a single radio. This filtering may be inadequate in a radio module prototype or hard to achieve on a low cost radio solution. As a result, solving these problems at a modular level may incur significant cost increases and time to market delays.
Features and advantages of embodiments of the claimed subject matter will become apparent as the following Detailed Description proceeds, and upon reference to the Drawings, wherein like numerals depict like parts, and in which:
Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended that the claimed subject matter be viewed broadly.
In general, the present disclosure includes systems and methods employing modified controlled impedance coaxial cables as well as systems and methods for manufacturing the same. The modified controlled impedance coaxial cables of the present disclosure may include one or more sections having an impedance which is different from the remainder of the coaxial cable such that one or more radio frequencies (RF) are filtered (e.g., blocked) and the modified controlled impedance coaxial cables operates as an in-line-filter. The modified controlled impedance coaxial cables may be configured to connect an antenna to a wireless module in a variety of computer platforms (including, but not limited to, a desktop personal computer (PC), a laptop, a notebook, an ultra mobile pc (UMPC), a handheld computing device, a game console, a multimedia appliance, a digital recording device for audio/video, a smart phone, a netbook computer system, tablet computers and the like).
Providing a coaxial cable having an in-line filter may reduce and/or eliminate the requirements of the filter on a wireless module, thereby leading not only to cost savings, but also improving radio coexistence performances of the computing platform while also reducing the real estate requirements needed to provide the desired isolation. Additionally, a coaxial cable having an in-line filter may also suppress the out-of-band (OOB) spurious emissions of a radio to help the radio to pass any regulatory tests.
The present disclosure also includes systems and methods for manufacturing modified controlled impedance coaxial cables. For example, the present disclosure includes systems and methods for manufacturing modified controlled impedance coaxial cables which require minimal changes to existing manufacturing techniques. As a result, the modified controlled impedance coaxial cable may be manufactured at a cost the same as, or similar to, standard coaxial cables having a constant impedance.
Turning now to
The computing device 102 may include a processor core 104, a display device 106 (for example, but not limited to, a conventional monitor, a liquid crystal display (LCD), a projector, and the like), a network interface device 115, memory 108 and/or 110, one or more wireless radio systems 200. The processor core 104 may include a processing unit of any type of architecture which has the primary logic, operation devices, controllers, memory systems, and so forth of the computing device 102. For instance, the processor core 104 may incorporate one or more processing devices and a chipset having functionality for memory control, input/output control, graphics processing, and so forth. The processor core 104 may be communicatively coupled via an interconnect 113 to a network interface device and/or a plurality of input/output (I/O) devices (collectively 115). The interconnect 113 may represent the primary high speed interconnects between components/devices of the host computing device 102, such as those employed in traditional computing chipsets. The interconnect 113 may be point-to-point or connected to multiple devices (e.g., bussed). The I/O devices 115 may include a variety of I/O devices configured to perform I/O functions such as, but not limited to, controllers/devices for input functions (e.g., keyboard, mouse, trackball, pointing device), media cards (e.g., audio, video, graphic), network cards and other peripheral controllers, LAN cards, speakers, camera, and the like.
The network interface device 115 may be configured to establish a connection (for example, wireless and/or wired connection) between the computing device 102 and one or more networks (such as, but not limited to, the Internet, an intranet, a peer-to-to peer network, and the like). The network interface 115 may be configured to perform a variety of signal processing functions associated with network communications.
The processor core 104 may also be coupled via a memory bus 117 to memory 108 and/or 110. According to one embodiment, memory 108 may include a “main” memory configured to store and/or execute system code and data. The “main” memory 108 may be implemented with dynamic random access memory (DRAM), static random access memory (SRAM), or any other types of memories including those that do not need to be refreshed. The “main” memory 108 may include multiple channels of memory devices such as DRAMs. The DRAMs may include Double Data Rate (DDR2) devices.
The computing device 102 may also include additional memory 110 such as, but not limited to, hard drive memory, removable media drives (for example, CD/DVD drives), card readers, flash memory and so forth. The memory 110 may be connected to the processor core 104 in a variety of ways such as via Integrated Drive Electronics (IDE), Advanced Technology Attachment (ATA), Serial ATA (SATA), Universal Serial Bus (USB), and so on. The memory 110 may also include one or more application modules 112 stored thereon that may be executed by the computing device 102 to provide a variety of functionality to the computing device 102. Examples of application modules 112 include, but are not limited, to an operating system, a browser, office productivity modules, games, email, photo editing and storage, multimedia management/playback, and the like. A variety of other examples are also contemplated.
As noted above, the computing device 102 may also include one or more wireless radio systems 200. The wireless radio systems 200 may include one or more antennas 114a-n, wireless radio module 116a-n, and modified controlled impedance coaxial cables 118a-n. For example, each antenna 114 may be communicatively coupled to a wireless radio module 116a-n via a modified controlled impedance coaxial cables 118a-n, for example, a radio frequency (RF) coaxial cable. The antennas 114a-n and wireless radio modules 116a-n may be located anywhere within/on the computing device 102. While the location of the antennas 114a-n and/or wireless radio modules 116a-n may be determined based on the specific application (for example, but not limited to, the size and/or shape limitations of the computing device 102), the antennas 114a-n may be disposed within the lid 120 while the wireless radio modules 116a-n may be disposed within the base 122. Those of ordinary skill in the art will recognize that the exact locations of the antennas 114a-n and/or wireless radio modules 116a-n may vary depending on the specific application and that the present disclosure is not limited to the arrangement illustrated unless specifically claimed as such.
Turning now to
According to at least one embodiment, the modified controlled impedance coaxial cable 118 may include at least one section 215a-n having a first impedance and at least one discontinuity section 228a-n. The first impedance section 215a-n may have any impedance. For example, the first impedance section 215a-n may include a 50 ohm RF coaxial cable such as, but not limited to, RG58, RG142, RG174, RG188, RG213, RG223, RG316, and the like. The present disclosure will refer to the first impedance section 215a-n as “a standard coaxial cable section 215a-n”; however, it will be understood that the first impedance section 215a-n is not limited to a 50 ohm RF coaxial cable unless specifically claimed as such.
The discontinuity section 228a-n may have a different impedance compared to the standard coaxial cable section 215a-n. Each discontinuity section 228a-n may have the same impedance; however, one or more of the discontinuity sections 228a-n may have a different impedance compared to one or more of the other sections 228a-n. As discussed herein, the length and/or number of the discontinuity sections 228a-n may be selected to allow one or more frequencies or frequency ranges to pass through the modified controlled impedance coaxial cable 118 with minimal attenuation while other frequencies or frequency ranges are either reflected and/or attenuated. As a result, a modified controlled impedance coaxial cable 118 consistent with the present disclosure may have two or more impedances along the length of the cable 118 rather than a constant impedance and the discontinuity sections 228a-n may therefore provide in-line filtering.
Turning now to
The impedance of the various sections 215a-n, 218a-n of the modified controlled impedance coaxial cable 118 may be determined, for example, based on the ratios of the diameters of the inner conductor 302, and outer diameter of dielectric layer 304 (inner diameter of outer conductive layer 306), as well as the configuration, dielectric material properties, and spacing of the layers 302-306 relative to one another. The impedance of coaxial cable 118 may be independent of the dimensions of the outer jacket 308. The length of the standard coaxial cable section 215a-n may have little impact on the overall impedance of the modified controlled impedance coaxial cable 118. For example, the following formula may be used for calculating the characteristic impedance of the modified controlled impedance coaxial cable 118 at the various sections 215a-n, 218a-n:
impedance=(138/ê(1/2))*log10(D/d)
Wherein d equals the diameter of the inner conductor 302, D equals the inner diameter of the cable shield 306 and e equals the dielectric constant of the dielectric layer 304.
Turning now to
The present disclosure also discloses systems and methods for manufacturing a modified controlled impedance coaxial cable 118,
Turning now to
Turning now to
According to one embodiment, the dies 724a-n may move along arrow A generally towards and away from each other. As the dies 724a-n move towards each other, the overall diameter of the inner conductor 702 may be reduced in at least one cross-sectional direction to form one or more discontinuity sections 728a-n having a different overall diameter relative to the standard coaxial cable sections 715a-n.
Alternatively, the dies 724a-n may be stationary relative to each other and one or more of the dies 724a-n may include one or more indentations and/or protrusions 726 configured to reduce the diameter of the inner conductor 702 to form the discontinuity sections 728a-n.
According to yet another embodiment, the system 700 may stretch the inner conductor 702, thereby reducing the outer diameter of the inner conductor 702 to form discontinuity sections 728a-n. For example, the system 700 may optionally include one or more heaters 718a which may heat the inner conductor 702, for example to a temperature at and/or near the glass transition and/or melting point. The heated inner conductor 702 may then be fed into one or more wheels 724a-n which may stretch the heated inner conductor 702, thereby reducing the overall diameter to form one or more discontinuity sections 728a-n with a different overall diameter relative to the standard coaxial cable sections 715a-n. The system 700 may also optionally include one or more coolers 718b to reduce the temperature of the inner conductor 702, for example, after the discontinuity sections 728a-n have been formed.
Turning now to
With reference now to
According to one embodiment, the dies 924a-n may move along arrow A generally towards and away from each other. As the dies 924a-n move towards each other, the overall diameter of the dielectric layer 904 may be reduced in at least one cross-sectional direction to form one or more discontinuity sections 928a-n with a different overall diameter relative to the dielectric layer 904 of the standard coaxial cable sections 915a-n. The dies 924a-n may be configured to reduce the diameter of only the dielectric layer 904 and/or to reduce the diameter of the dielectric layer 904 and the inner conductor 902 in one or more discontinuity sections 928a-n.
Alternatively, the dies 924a-n may be stationary relative to each other and one or more of the dies 924a-n may include one or more indentations and/or protrusions 926 configured to increase and/or reduce the diameter of the dielectric layer 904 and/or inner conductor 902 to form one or more discontinuity sections 928a-n. The dies 924a-n may also be configured to remove either at least a portion of the dielectric layer 904 in one or more of the discontinuity sections 928a-n (for example, but not limited to, all of the dielectric layer 904).
According to yet another embodiment, the system 900 may stretch the dielectric layer 904 and/or inner conductor 902, thereby reducing the outer diameter of the dielectric layer 904 and/or inner conductor 902 to form discontinuity sections 928a-n. For example, the system 900 may optionally include one or more heaters 918a which may heat the dielectric layer 904 and/or inner conductor 902, for example to a temperature at and/or near the glass transition and/or melting point. The heated dielectric layer 904 and/or inner conductor 902 may then be fed into one or more wheels 924a-n which may stretch the heated dielectric layer 904 and/or inner conductor 902, thereby reducing the overall diameter to form one or more discontinuity sections 928a-n with a different overall diameter relative to the standard coaxial cable sections 915a-n. The system 900 may also optionally include one or more coolers 918b to reduce the temperature of the dielectric layer 904 and/or inner conductor 902 after the discontinuity sections 928a-n have been formed.
Turning now to
With reference to
According to one embodiment, the dies 1124a-n may move along arrow A generally towards and away from each other. As the dies 1124a-n move towards each other, the overall diameter of the outer conductor 1106 may be reduced in at least one cross-sectional direction to form one or more discontinuity sections 1128a-n with a different overall diameter relative to of the outer conductor 1106 of the standard coaxial cable sections 1115a-n. The dies 1124a-n may also reduce the diameter of the dielectric layer 1104 and/or the inner conductor 1102.
Alternatively, the dies 1124a-n may be stationary relative to each other and one or more of the dies 1124a-n may include one or more indentations and/or protrusions 1126 configured to or reduce the diameter of the outer conductor 1106 in the discontinuity sections 1128a-n. Again, the dies 1124a-n may also reduce the diameter of the dielectric layer 1104 and/or the inner conductor 1102.
According to yet another embodiment, the system 1100 may stretch the outer conductor 1106, thereby reducing the outer diameter of the outer conductor 1106 to form discontinuity sections 1128a-n. For example, the system 1100 may optionally include one or more heaters 1118a which may heat the outer conductor 1106, for example to a temperature at/near the glass transition and/or melting point. The heated outer conductor 1106 may then be fed into one or more wheels 1124a-n which may stretch the heated outer conductor 1106, thereby reducing the overall diameter in discontinuity sections 1128a-n relative to the standard coaxial cable sections 1115a-n. The system 1100 may also optionally include one or more coolers 1118b to reduce the temperature of the outer conductor 1106 after the discontinuity sections 1128a-n have been formed. Again, the system 1100 may also be configured to reduce the diameter of dielectric layer 1104 and/or the inner conductor 1102 at the same time as the outer conductor. Care should be taken when stretching the outer conductor 1106 to prevent leakage of the signal to be transmitted.
Turning now to
According to one embodiment, the dies 1224a-n may move along arrow A generally towards and away from each other. As the dies 1224a-n move towards each other, the overall diameter of the modified controlled impedance coaxial cable 1218 may be reduced in at least one cross-sectional direction to form one or more discontinuity sections 1228a-n with a different overall diameter relative to the standard coaxial cable sections 1215a-n. The dies 1224a-n may also reduce the diameter of the sheath 1208 and at least one of the outer conductor 1206, the dielectric layer 1204 and/or the inner conductor 1202.
Alternatively, the dies 1224a-n may be stationary relative to each other and one or more of the dies 1224a-n may include one or more indentations and/or protrusions 1226 configured to increase and/or reduce the diameter of the sheath 1208 in the discontinuity sections 1228a-n. Again, the dies 1224a-n may also reduce the diameter of the sheath 1208, the dielectric layer 1204 and/or the inner conductor 1202.
According to yet another embodiment, the system 1200 may stretch the modified controlled impedance coaxial cable 1218 (e.g., the sheath 1208 and at least one of the outer conductor 1206, dielectric layer 1204, and/or inner conductor 1202) thereby reducing the outer diameter of the modified controlled impedance coaxial cable 1218 to form discontinuity sections 1228a-n. For example, the system 1200 may optionally include one or more heaters 1218a which may heat the modified controlled impedance coaxial cable 1218, for example to a temperature at/near the glass transition and/or melting point. The heated modified controlled impedance coaxial cable 1218 may then be fed into one or more wheels 1224a-n which may stretch the heated modified controlled impedance coaxial cable 1218, thereby reducing the overall diameter in discontinuity sections 1228a-n relative to the standard coaxial cable sections 1215a-n. The system 1200 may also optionally include one or more coolers 1218b to reduce the temperature of the modified controlled impedance coaxial cable 1218 after the discontinuity sections 1228a-n have been formed.
The insertion loss of an exemplary modified controlled impedance coaxial cable consistent with at least one embodiment of the present disclosure is generally illustrated in
For example, a modified controlled impedance coaxial cable for a 2.4 GHz WiFi radio may be configured to reject 3G signals (e.g., signals at and below 2 GHz) while passing WiFi, WiMAX frequencies (e.g., 2.4 GHz, 2.6 GHz, 3.5 GHz, and 5 GHz). Such an arrangement may improve the antenna isolation between WiFi and 3G antennas and provide stronger rejection to uplink signal around 2 GHz transmitted by a 3G radio co-located on the same computing device platform and operating concurrently. Similarly, a modified controlled impedance coaxial cable may also be configured to operate at the Bluetooth radio transmitting band (e.g., 2.4 GHz range) to limit its out of band emission in 2.5 GHz band, which could significantly degrade a WiMAX radio's performance. Moreover, the modified controlled impedance coaxial cable may be configured to operate in the DTV radio band and to reject 3G radio band uplink frequencies (e.g., 700-900 MHz) to ensure a good UHF DTV reception.
Accordingly, the modified controlled impedance coaxial cable may improve the isolation between antennas of two different radios operating at close frequency bands, lowering susceptibility to front-end saturation due to very strong OOB interference signals. Additionally, the modified controlled impedance coaxial cable may improve the radio co-existence performances.
According to one aspect, there is disclosed a method for manufacturing a modified impedance coaxial cable. The method may include obtaining a coaxial cable having an inner conductor, a dielectric layer at least partially covering an outer surface of the inner conductor, and an outer conductor at least partially covering an outer surface of the dielectric layer. As used herein, the term “obtaining” is intended to mean either acquiring a coaxial cable which has already been manufactured as well as manufacturing a coaxial cable. The coaxial cable may include a first section having a first impedance configured to allow a first frequency band to pass. A discontinuity section may be formed in at least one of the inner conductor, the dielectric layer, and the outer conductor. The discontinuity section may have an impedance different than said first impedance and a length configured to attenuate a second frequency band.
According to another aspect, there is disclosed a method including forming a coaxial cable having a dielectric layer disposed around a least a portion of an inner conductor, the coaxial cable including a first section configured to allow a first frequency band to pass; and selectively modifying the coaxial cable to form a plurality of discontinuity sections, wherein at least one of the inner conductor, the dielectric layer, and the outer conductor has a different diameter in the discontinuity sections compared to the first section such that the each of the plurality of discontinuity sections has a length configured to attenuate a second frequency band.
According to yet another aspect, there is disclosed a method including forming a coaxial cable by selectively forming a first section and at least one discontinuity section, wherein the first section has a first impedance configured to allow a first frequency band to pass, and wherein at least one of an inner conductor, a dielectric layer, and an outer conductor of the coaxial cable has a different impedance in the discontinuity sections compared to the first impedance such that the each of the plurality of discontinuity sections is configured to attenuate a second frequency band.
Various features, aspects, and embodiments have been described herein. The features, aspects, and embodiments are susceptible to combination with one another as well as to variation and modification, as will be understood by those having skill in the art. The present disclosure should, therefore, be considered to encompass such combinations, variations, and modifications.
The terms and expressions which have been employed herein are used as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described (or portions thereof), and it is recognized that various modifications are possible within the scope of the claims. Other modifications, variations, and alternatives are also possible. Accordingly, the claims are intended to cover all such equivalents.
This application is a continuation-in-part of U.S. patent application Ser. No. 12/590,353, filed on Nov. 11, 2009 and entitled RADIO FREQUENCY FILTERING IN COAXIAL CABLES WITHIN A COMPUTER SYSTEM, which is fully incorporated herein by reference.
Number | Date | Country | |
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Parent | 12590353 | Nov 2009 | US |
Child | 12975433 | US |