Patent Publication Number: US-2009231223-A1

Title: Compact remote tuned antenna

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/065,788, filed Feb. 14, 2008. 
    
    
     FIELD OF THE DISCLOSURE 
     This disclosure relates to antennas which are compact and electrically long, are effective for frequencies from long wave to microwave, and have remotely tuned narrow bandwidths for use in radio communications. More specifically, the disclosure relates to compact antenna devices including planar, coplanar and combined planar/coplanar sets of radiating/receiving elements made of spaced apart conducting loops. 
     BACKGROUND OF THE DISCLOSURE 
     The Amateur Radio Service of the United States and Amateur Radio Services of other countries are often the only communications services that remain working after the occurrence of natural and other disasters. There is a need in these services for a compact light weight antenna that can be easily stored in a hardened structure and then, when needed under post disaster conditions, transported and quickly set up without requiring long adjustments in a temporary tent or damaged, but usable, structure. 
     There is also a need for an antenna that is low profile; that trades off height and length for volume; and that can replace in operation at ground height the conventional tall monopole and long dipole antennas (as well as their supporting structures) now used for permanent point to point mobile and broadcast applications, with useable effective radiated power (ERP) results over the frequency ranges of VLF (very low frequency, nominally 3-30 KHz), LF (low frequency, normally 30-300 kHz), MF (medium frequency, nominally 300-3,000 kHz) and HF (high frequency, nominally 3-30 MHz) communications. 
     The advantages of such antenna devices have been recognized by amateur and professional planners of disaster communications since the early days of radio. Attempts to improve and develop such antenna devices have continued in more recent years with only moderate success. 
     The advantages of low radiation angle and horizontal polarization for long range HF communication have been recognized for many years and have driven the development of the HF beam and quad-type directional antennas to their present state in the art. However, the development of an omni-directional antenna with improved low radiation angle and horizontal polarization characteristics still leaves much to be desired. This is particularly true in the case of portable, compact omni-directional antennas which, because of their unique simplicity, are far more favorable for use in disaster communications than the larger, heavier and more complicated HF beam and quad antennas. 
     Because of their simplicity, omni-directional antennas are more adaptable to use with remote controlled tuning enabling operation from a location distant from the antenna itself. For example, in the case of a natural disaster, the omni-directional antenna might be erected on top of a damaged building, while the station itself could be controlled from a remote location. Also, under certain field conditions, where a generator and fuel supply are necessary, the antenna might be installed at a distance of several hundred feet from the operating position for safety and for mechanical and electrical noise considerations. 
     SUMMARY OF THE DISCLOSURE 
     In accordance with the disclosure, a compact antenna device includes planar, coplanar and combined planar/coplanar sets of radiating/receiving elements made of spaced apart loops of wire, sheet metal, or other electrical conductors embedded, printed or plated on or in an insulating substrate material that is transparent to radio frequencies. Suitable substrates include ribbon wire and circuit board with the width, diameter, thickness, length and spacing of the conductors ranging in size from meters to millimeter and in configurations that maximize useful radio frequency (RF) radiation in a horizontal direction plane with high phase coherency of radiation and optionally including a remote controlled tuning capability. 
     An improved compact antenna embodying the disclosure may replace the high radiation efficiency, full size electrical length dipole and monopole antennas commonly used in VLF to microwave frequency ranges, and can efficiently transmit RF energy in a reduced volume, length, width and height package, both in temporary and in permanent applications. Such a compact antenna may also have remote controlled tuning over entire bandwidth ranges of the VLF, HF and microwave frequency bands. 
     Furthermore, in accordance with the disclosure, an improved antenna system is provided for introducing RF energy at high RF current levels to an antenna-radiating element, which has a low series inductance value to reduce voltage across the element. Such an improved antenna system may be compact and efficient and have an improved receive aperture that can support remote indoor or outdoor operation. 
     An improved compact antenna system according to the disclosure may be configured for omni-directional, horizontal, low angle of radiation operation in a relatively small package and at the same time can be operated at high RF power levels; the system may also include an RF tuning component that can tune the antenna at high RF power levels from a remote location. The antenna may be configured and fitted to a number of existing towers, supports and other structures. 
     In addition, an RF tuning apparatus is provided for tuning a compact antenna that can efficiently handle high RF power levels of greater than about 1500 watts RMS, and may remotely tune a compact antenna system at high RF current levels. In an embodiment, this RF tuning apparatus has a minimum number of moving parts, may be configured for a number of bands and be tuned relatively quickly within a given band, and may be housed in a small waterproof box at an antenna location remote from the transmitter and receiver. 
     In accordance with the disclosure, a simple and reliable parallel interface capability may be provided to a wide variety of remotely located computer devices in order to support automatic program control and turning of an antenna system. 
     Furthermore, in accordance with the disclosure, an improved compact antenna system is provided that is configured for omni-directional, isotropic all angle radiation operation in a relatively small package, and which at the same time can be operated at high RF power levels. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         FIG. 1  is an electrical schematic view of an antenna system in accordance with an embodiment of the disclosure. 
         FIG. 1A  is a detail view of a capacitor/inductor series circuit for use in the system of  FIG. 1 , to improve the effective radiated power (ERP) of the system. 
         FIG. 1B  is a detail view of a capacitor/inductor circuit for use in the system of  FIG. 1 , to improve tuning of the system for maximum ERP. 
         FIG. 2  is a schematic diagram illustrating planar RF radiation emanating from a less than ½ wavelength loop. 
         FIG. 3  is a schematic diagram illustrating planar RF radiation emanating from a coplanar stack of a set of two less than ½ wavelength loops connected in a series circuit. 
         FIG. 4  is a schematic diagram illustrating planar RF radiation emanating from a series connected set of five less than ½ wavelength rectangular loops. 
         FIG. 5  is an electrical schematic view of a single round loop that with connection leads form a less than ⅛ wavelength coplanar loop antenna with apparatus normally required to tune and match that antenna. 
         FIG. 6  is an electrical schematic view of a set of two round loops of the  FIG. 5  description type in series connection that with leads form a less than ¼ wavelength coplanar loop set antenna with apparatus normally required to tune and match such an antenna. 
         FIG. 7  is an electrical schematic view of a set of four round loops of the  FIG. 5  type in series connection that form a less than  1  wavelength greater than ½ wavelength coplanar loop set antenna with apparatus normally required to tune and match such an antenna. 
         FIG. 8  is an electrical schematic view of a set of eight round loops of the  FIG. 5  type in series connection with leads that form a 1 wavelength loop antenna with apparatus normally required to match such an antenna. 
         FIG. 9  is an electrical schematic view of a single planar square loop in the plane indicated. 
         FIG. 10  is an electrical schematic view of a single planar set of four wide spaced series connected rectangular loops in the plane indicated. 
         FIG. 11  is an electrical schematic view of a single planar set of four very close spaced series rectangular loops in the plane indicated. 
         FIG. 12  is an schematic view of two of  FIG. 9  planar loops in a coplanar arrangement in and above the plane indicated; 
         FIG. 13  is a schematic view of a combination of two  FIG. 11  single planar sets of four very close spaced series connected rectangular loop sets mounted over four rectangular planar close spaced series connected loops to form a coplanar set of planar loop sets. 
         FIG. 14  is a schematic view of  FIG. 13  coplanar loop set with connection method to form a set of eight planar loops. 
         FIG. 15  is a side view of  FIG. 14  showing radiation and placement of energy guide plates. 
         FIG. 16  is a top view of  FIG. 14  showing omni directional horizontal radiation from the set of planar loops. 
         FIG. 17  is a planar set of close spaced wire loops with a binary 1:2:4 length ratios with leads back to a set of relays, where insulated wire is used. 
         FIG. 18  is a planar set of printed wire circuit board loops with a binary 1:2:4 length ratios with leads back to a set of relays, where insulation by board gap space is used. 
         FIG. 19  is an exploded view showing a part of a loop stack assembly with an arrangement of energy guide plate, flat insulator plate, planar loop set, inside cavity insulator, flat insulator plate, energy guide plate, flat insulator plate, second planar loop set, cavity insulator, and flat insulator plate. 
         FIG. 20  shows a top view of a portable or mobile unit with a plastic cover over an aluminum base plate. 
         FIG. 21  shows a side view of the portable or mobile unit with the plastic cover removed. 
         FIG. 22  depicts a land vehicle with isotropic all angle radiation type unit, suitable for ground to air and short range ground to ground communications. 
         FIG. 23  depicts a vessel with omni directional low angle long range low angle radiation type unit mounted below radar antenna on a mast. 
         FIG. 24  shows an aircraft with isotropic all angle radiation type unit, suitable for air to ground and air to air communications. 
         FIG. 25  shows an emergency shelter set up with an isotropic all angle radiation type unit. 
         FIG. 26  schematically illustrates an antenna system including an RF input section circuit and a control monitor connected by a wire buss. 
         FIG. 27  schematically illustrates an antenna system as in  FIG. 26 , with the addition of a remote controlled inductance device. 
         FIG. 28  schematically illustrates an antenna system as in  FIG. 27 , with the addition of a second remote controlled inductance device and a remote controlled capacitor device. 
         FIG. 29  schematically illustrates an antenna system as in  FIG. 26 , with the addition of a twin “T” manual adjustable matching device, capacitor devices and a manual adjustable inductor device. 
         FIG. 30  schematically illustrates an antenna system as in  FIG. 26 , with the addition of a fixed capacitor ratio twin “T” remote controlled adjustable inductor device and a fixed matching capacitor device. 
     
    
    
     Like reference numbers and designations in the various drawings indicate like elements. 
     DETAILED DESCRIPTION  
     The term “electrical length,” when used herein, means the length of a conductor corrected for the speed of light in that conductor (a wire or other type of conductor, or transmission line device). 
     In the embodiments described herein, an electromechanical relay or other switch device is used to control, remotely and by a parallel binary bit pattern, one or more arbitrary radiating structures. These structures are formed of series connected, absolute binary sequence electrical length radiating elements in a main circuit loop; the main loop is characterized by a total main loop electrical length. The radiating arbitrary structures are formed from individual electrical length elements, and/or sets of elements insulated and isolated from each other. These binary electrical length elements may also be insulated and isolated by 1:1 balun or other transformer devices. The binary length elements may be connected to switch devices by wire or coax cable. The binary controlled switch devices may un-short (and thereby connect or disconnect), or short out (and thereby bypass) the binary length elements in the main loop circuit. The electrical length of this main loop circuit can be set to a desired length, which may range from a maximum length given by the total length of all the binary length elements in series (un-shorted) to a minimum length where all the binary elements are shorted out and effectively bypassed. This operation can be performed by a remote control, by establishing a binary control bit pattern by manual or computer or other automatic means. This binary control bit pattern can then be sent over the control cable, over a great distance, to control switch devices in a binary pattern. The ascending binary electrical length radiating elements of a main loop can be any combination of radiating structures; loop, dipole or monopole. The electrical length of this arbitrary structure is adjusted to natural fundamental or harmonic resonance conditions. The establishment of such resonance conditions simplifies the requirements to match a standard transmission line to antenna to a very efficient wide band 1:1 type transmission line or other 1:1 transformer device. Adjustment of the main loop length, and use of a 1:1 transformer, can effect an efficient matching condition to coax cable in the 35 ohm to 52 ohm characteristic impedance range with very low standing wave ratios, so as to assure a very high effective radiated power level. 
     In an embodiment, the radiating structure comprises a set of planar conducting loops having an electrical length of less than ½ wavelength, in a series connection with switching devices (e.g. relays). In other embodiments, the radiating structure may comprise a set of coplanar loops, or a set of planar and coplanar loops in combination. 
     In alternative embodiments, one or more of the radiating structures may comprise 
     (a) a dipole device having an electrical length of less than ½ wavelength, with a balun, coax cable, and balun in a switched series circuit connection; 
     (b) a monopole device having an electrical length less than ¼ wavelength, with a balun, coax cable, and balun in a switched series circuit connection; 
     (c) a set of planar loops in a series connection, the loops having a rectangular, square, round or some other shape and having an electrical length of less than ½ wavelength, with a wide spacing of loops, to produce low angle linearly polarized omni directional horizontal radiation; 
     (d) a set of planar loops in a series connection, the loops having a rectangular, square, round or some other shape and having an electrical length of less than ½ wavelength, with a narrow spacing of loops (that is, about ¼ inch between the planes of neighboring loops), to produce all angle isotropic type un-polarized radiation; 
     (e) a set of coplanar loops in a series connection, the loops having a rectangular, square, round or some other shape and having an electrical length of less than ½ wavelength, with a wide spacing of loops, to produce low angle linearly polarized omni directional horizontal radiation; 
     (f) a set of coplanar loops in a series connection, the loops having a rectangular, square, round or some other shape and having an electrical length of less than ½ wavelength, with a narrow spacing of loops, to produce all angle isotropic type un-polarized radiation; 
     (g) a set of planar and coplanar loops in combination, in a series connection and having a rectangular, square, round or some other shape and having an electrical length of less than ½ wavelength, with a narrow spacing of loops, to produce all angle isotropic type un-polarized radiation; or 
     (h) a set of planar and coplanar loops in combination, in a series connection and having a rectangular, square, round or some other shape and having an electrical length of less than ½ wavelength, with a wide spacing of loops, to produce low angle linearly polarized omni directional horizontal radiation. 
     In any and all of the above arrangements, the loop sets, when switched into the main loop, contribute to the main loop length. Accordingly, the main loop length may be adjusted by switching selected elements to effect an efficient matching condition to coax cable in the 35 ohm 52 ohm characteristic impedance range with very low standing wave ratios. Using a 1:1 transformer assures a very high effective radiated power level. 
     An antenna system according to the disclosure has a series arrangement of closely spaced apart, small, rectangular or circular loops stacked together in a plurality of sets, each set being separately connected electrically via separate relays for each set of loops. The tuning device can be manual or automatic, which in the case of the latter would be digitally controlled to achieve minimum SWR (standing wave ratio, a measure of how much radio energy being sent into an antenna system is being reflected back to the transmitter). The manual or computer controlled remote tuning system has a set of switched planar, coplanar or combined planar/coplanar loop radiating receiving loop element sets, connected in a series circuit. The total inside loop perimeter length of all loop set series loops, added to the total length of the wires connecting the loops in a set to each relay switch device contact, is made to be a specific total length. The relay contacts are arranged to disconnect series loop element sets and bypass loop element sets if relays are un-energized. A typical total of 16 relay devices are employed to disconnect and bypass series loop element sets into and out of a main RF series loop circuit. In addition, in series with this main RF circuit loop, a 1:1 type wide band transmission line balun device may be connected. This balun device, in series with all other main loop switched elements, is used to output received RF signals to a coaxial cable with connection to coax through a standard, female type, UHF (ultra high frequency, nominally 300-3000 MHz) or other panel connector device. 
     This main loop circuit has the series connected, relay switched, planar, coplanar and combined planar/coplanar collection of radiating/receiving series loop set elements with total loop set lengths arranged in a descending absolute binary electrical length sequence. The electrical length of individual loop set elements is arranged in a binary sequence: 2 0 , 2 1 , 2 2 , 2 3 , 2 4 , . . . , 2 n . The loop set elements thus have lengths in the ratio 1:2:4:8:16 and so forth. The shortest wire length may be 1 meter, 1 ft, 1 inch, 1 cm, etc.; the other wire lengths are then multiplied according to the sequence 2, 4, 8, 16, . . . , 2 n . In the embodiments described herein, the basic (shortest) length is taken to be 1 ft. 
     In an exemplary embodiment, 16 relays are arranged in parallel to form a sequence ranging from a least significant bit, LSB (0) to a most significant bit, MSB (15); accordingly, the control lines for the relays express a binary code value. When the control lines of the  16  relays are energized with a LSB to MSB digital code bit pattern, the electrical length in feet is the decimal number equivalent of the binary code value. In actual operation any energized relay is a binary 1 and any un-energized relay is a binary 0 value. The LSB bit is the control line status of the relay that is switching the shortest length of wire; the MSB bit is the control line status of the relay that is switching the greatest length of wire with all relay status bits in ascending order according to the lengths of wire switched. The total length of a switched loop set is given by the perimeter lengths of the loops plus the length of the loop connecting wires. For example, if the length of the wires connecting the loops to the relays is 5 ft, then a setting for a decimal value of 975 feet of loops, plus 5 ft of typical inter relay and other main loop series wire, will cause the main loop to have 980 ft of electrical length. The coaxial connector will present a good 1.11 SWR to 1.2 SWR match to 50 ohm signal source of approximate frequency of 936/980=0.960 MHz frequency. The fact that the main loop electrical length can be set to any maximum to minimum length value permits the main loop to be remotely set to any frequency (in theory) remotely by relays from a total loop length value in feet divided into 936, to a minimum loop set length (that is, the shortest loop set length in feet) divided into 936. If this length is 25 ft, then the corresponding frequency is 936/25=37 MHz. The actual range can be less by about 20 percent on each end of the range due to loop to loop capacitance, mutual inductance and other effects. The above-described binary loop gives the widest tuning range for the least amount of loop conductor/wire and switching relays and is accordingly a desirable configuration for remote control by a digital computer parallel output port. 
     Some portable, fixed and mobile applications for the present antenna in the HF frequency range include: amateur radio service transmitting and receiving, and receiving short wave listening with reduced signal fade. Some special MF frequency range applications include: low power AM radio broadcast for public service information and traffic warnings and advisories; private AM broadcast systems for ski and other resorts; high power AM broadcast station use as primary and emergency antenna or split site applications; FM broadcast band and television broadcast receiving applications; and VHF, UHF and microwave communications services. Some particular MF to long wave applications include: affordable two way underground-to-surface communications (e.g. from coal and other mines) for normal and emergency communications; and underground natural resource exploration for commercial and scientific research applications. 
       FIG. 1  illustrates an embodiment of a compact remote tuned antenna having planar co-planar and combined planar co-planar loop sets of rectangular loop antennas of varying descending binary lengths (that is, lengths expressed as powers of 2). Exemplary is planar loop set  35  across terminals  79 ,  80  of length 16 ft, in combination with planar loop set  34  across terminals  77 ,  78  of length 8 ft, in combination with planar loop set  33  across terminals  75 ,  76  of length 4 ft, in combination with planar loop set  32  across terminals  73 ,  74  of length 2 ft, in combination with planar loop set  31  across terminals  71 ,  72  of length 1 ft. Operation of relays  51 ,  52 ,  53 ,  54 ,  55  permits the selection of all antenna lengths from 1 ft to 31 ft in 1 ft increments. Each individual loop and the connecting wire are counted in the total loop set length connected to the relay terminals. 
     The terminals described herein are generally standard wire, spade-lug, banana-jack terminals. Planar loop  31  connected across terminals  71 ,  72  is 1 ft in length. Planar loop  32 , connected across terminals  73 ,  74  is 2 ft in length. Planar loop  33  connected across terminals  75 ,  76  is 4 ft in length. Planar loop set  34  connected across terminals  77 ,  78  is 8 ft in length. Planar loop set  35  connected across terminals  79 ,  80  is 16 ft in length. Coplanar loop set  36  connected across terminals  81 ,  82  is 32 ft in length. Coplanar loop set  37  connected across terminals  83 ,  84  is 64 ft in length. Coplanar loop set  38  connected across terminals  85 ,  86  is 128 ft in length. Coplanar loop set  39  connected across terminals  87 ,  88  is 256 ft in length. Planar loop set  40  connected across terminals  89 ,  90  is 512 ft in length. Planar loop set  41  connected across terminals  91 ,  92  is 1024 ft in length. Planar loop set  42  connected across terminals  93 ,  94  is 2048 ft in length. Planar loop set  43  connected across terminals  95 ,  96  is 4096 ft in length. Planar loop set  44  connected across terminals  97 ,  98  is 8192 ft in length. Planar loop set  45  connected across terminals  99 ,  100  is 16384 ft in length. Planar loop set  46  connected across terminals  101 ,  102  is 32768 ft in length. Planar loop sets  42 - 46  may be used to verify operation from 0.014 MHz to 35 MHz. 
     In the construction of this embodiment, the individual planar loops  31 ,  32  and  33  are made from stranded (number 14) 600 volt insulated wire tacked to ⅜ inch thick wood panels with standard wire tacks. The individual planar loop sets  34  and  35  are constructed of stranded (number 14) 600 volt insulated wire tacked to a ⅜ inch thick wood panel with standard wire tacks as two series connected rectangular planar loops. The individual loops in these sets are generally rectangular, 1.5 ft by 0.5 ft. The length of the four long loop wires is approximately 1.5 ft long with 2 inch spacing. The individual planar loops of coplanar loop sets  36 ,  37 ,  38 ,  39  are constructed of stranded (number 14) 600 volt insulated wire mounted above each other in a vertical wood insulating frame with the coplanar space between individual loops being nominally 5 inch. The individual coplanar loops of loop sets  36 ,  37 ,  38  and  39  are 2 ft by 2.5 ft when mounted in a frame; the length of a loop with a 1 ft lead length is 10 ft. To form the 32 ft total length loop, 3 coplanar loops of 10 ft are mounted and 2 ft of wire used for leads. To form the 64 ft total length loop, 6 coplanar loops of 10 ft are mounted and 4 ft of wire used for leads. To form the 128 ft total length loop, 12 coplanar loops of 10 ft are mounted and 8 ft of wire used for leads. To form the 256 ft total length loop, 24 coplanar loops of 10 ft were mounted and 14 ft of wire used for leads; the 12 ft structure of 24.5 ft spaced loops was made in two approximately 6 ft tall frames. The 14 ft length of lead wire in the 256 ft total was used to interconnect the two coplanar loop frames. To verify operation from 460 kHz to 30 MHz, two temporary planar rectangular closely spaced loops were constructed of 512 ft and 1024 ft of stranded number 14 600 volt insulated wire. Construction of these loops was accomplished by laying out twenty 25 ft long wires with 5 inch spacing to form ten 25 ft by 5 inch spaced rectangular loops. The same procedure was used for the 1024 ft loop to form loops  40  and  41  shown schematically in  FIG. 1 . 
     As shown in  FIG. 1 , four contact standard RS232 connectors  25  are used. Connector  23  is a fixed chassis mount contact female connector; connector  24  a movable contact male connector; connector  26  a movable contact female connector; and connector  27  a fixed chassis mount contact male connector. 
     As shown in  FIG. 1 , at connectors  23 - 27  wires  69  and  70  connect to wires  68  and  67  respectively, wire  103  serves as a common chassis ground return, and the sixteen relays  51 - 66  connect to a tuning box with an array of sixteen switches  1 - 16 , described in more detail below. 
     Closing switch  1  connects  12  VDC source  20  to relay  51 , which energizes relay  51  and un-shorts and connects loop  31  (1 ft long). Closing switch  2  connects  12  VDC source  20  to relay  52 , which energizes relay  52  and un-shorts and connects loop  32  (2 ft long), and so forth. 
     A local manual control monitor tune box includes connector  23 , wiring conductive chassis common ground, single pole single throw (SPST) switches  1 - 16 , forward SWR indicator display  12  volt DC meter  22  reverse SWR indicator display meter  21  and 12 volt battery  20 . Note that battery  20  can be replaced by a 12 VDC type power supply in some applications. The local manual control monitor tune box may be constructed in various waterproof cases for outdoor use, as well as rack panel instrument cases for indoor use. Various on/off switch indicator lamps and fuse arrangements may be used, as is known to those skilled in the art. Other improvements, such as transient diodes and transient suppressor devices to prevent switch erosion, may be readily implemented by those skilled in the art. 
     In this embodiment, the remote control monitor tune box also includes connector  27 ; wiring conductive chassis as common ground  103 ; connector  28 ; sensor  29 ; transformer  30 ; relays  51 - 66 ; and spade lug connectors  71 - 102 . The remote control monitor tune box is a plastic NEMA (National Electrical Manufacturers Association) style outside power plastic junction box the antenna loop set leads are all connected by spade lug banana wire jack connectors through individual holes in side of plastic NEMA type box. If a metal box is used the spade lug connectors can be insulated by rubber grommets or other suitable insulators. 
     The sixteen contacts of connector  27 , connected to the respective planar loop sets  31 - 46 , may be viewed as control bits for the remote control box. The contact for loop set  31  is the LSB binary control bit 0; the contact for loop set  46  is the MSB binary control bit 15. 
     Device  30  is a one to one wide band transmission line transformer made of ten turns of number RG 58-coax cable on an AMIDON FT-240-K core device (Amidon Inc. Casa Mesa, Calif.). Connector  28  is an UHF type coax panel connector. Device  29  is a standard 50-ohm coax input and output SWR power sensor device. Wire  68 , connected to wire  69  through the connectors described above, is the forward SWR signal voltage line to remote display unit meter  22 . Wire  67 , connected to wire  70 , is the reverse SWR signal voltage line to remote display unit meter  21 . The return signal voltage from the remote display units is returned through common ground  105 . Connector  27  has several pins connected to the common ground and return line through cable  25 , as shown schematically in  FIG. 1 . 
     In this embodiment, cable assembly  25  is a standard shielded plastic molded 25-wire straight wired connector contact (PHILMORE ROCKFORD, Ill. 51109 U.S.A. RS232 DATA CABLE FULL SHIELD-DB25 MALE/FEMALE 100 FT. STRIGHT THRU WIRING NO. 70-2580) to contact one to one RS-232 standard cable assembly. Antenna control and monitor lines are connected from manual control to using this cable. Remote control may be performed with cables at least as long as 400 feet. 
     In the embodiment shown in  FIG. 1 , relays  51 - 66  are type Magnecraft General Purpose Relays DPDT 15 A, MINI POWER Mfg Part NUMBER: 782XBXM4L-12D. In mounting the relays to a board or chassis, Magnecraft Relay Sockets and Accessories Mfg P/N 70-401-1 8 PIN SOLDER TERM may be used. 
     The radiating elements shown in  FIG. 1  are generally folded with close spacing, as schematically illustrated in planar loop sets  34  and  35  of  FIG. 1 . This has an effect on the observed self-inductance of the radiating elements. In the case of a long wire or a large circular or square loop, this inductance is obtained from the physical length: the length of the loop in ft (or a section of a loop element spacing with physical length in ft) when multiplied by 0.384 micro henry/ft., corresponds to the universal permeability constant 1.26×10 −6  henry/meter converted to 0.384 micro henry/ft. When the conductor is folded with close spacing, however, the self-inductance is reduced, and may approximate 0.192 micro henry/ft (that is, half the amount for an unfolded conductor), which in turn increases the value of the self-resonant frequency by a factor of 4. This effect has been observed in the closely spaced folded loop sets used in the embodiment of  FIG. 1 , over the frequency range 1.8 MHz to 800 MHz. It has also been observed that the reduced inductance at resonance conditions, due to closely spaced planar loops as in  FIG. 1 , results in reduced effective radiated power (ERP). This problem is addressed by adding a circuit as shown in  FIG. 1A  at location  1000  (that is, between the balun device  30  and the array of planar loop sets). The two wires connecting the balun device and the planar loop sets connect with this circuit at terminals  1001 - 1004 , as shown in  FIG. 1A . The circuit includes a binary switched inductor  1010  in series with a variable capacitor  1020 ; the capacitor is preferably variable in the range 0.7 pF to 1000 pF and has a high voltage rating (20000 V or more). 
       FIG. 1B  schematically illustrates a tuning circuit that may advantageously be located at  1000  in the system of  FIG. 1 , in order to maximize ERP output of the antenna system. Variable capacitors  1051 ,  1052  are connected in series between terminals  1001  and  1003 ; variable capacitors  1053 ,  1054  are connected in series between terminals  1002  and  1004 . Capacitors  1051 - 1054  are all variable from 2 pF to 2000 pF. Pairs of capacitors  1051 ,  1053  and  1052 ,  1054  may be tuned together, for example by being turned from common insulated rotor shafts shown schematically at  1055 ,  1057  respectively. A variable inductance  1060  connects the junctions between the pairs of capacitors, as shown. With this circuit added to the arrangement of  FIG. 1 , it has been observed that the planar loop array electrical length may be set to ⅝ to ⅞ of a wavelength for the frequency of interest, while the capacitors  1051 - 10545  and inductor  1060  are used to adjust the antenna for resonance; a 1:1 SWR may then be obtained. 
     It will be appreciated that relays  51 - 66 , with their associated contacts and connectors, together comprise a relay switching device for the antenna system; this device is advantageously remotely controlled. 
     A simple radiating structure, illustrated in  FIG. 2 , is a less than ½ wavelength perimeter planar loop, with emitted planar radiation symbol  201 . The radiation pattern indicated in plane  200  is also the same general type planar low angle radiation pattern that has been observed to occur in square and triangular loops and rectangular loops with length to width ratio of 2:1.  FIG. 5  depicts a round, approximately 5.25 ft diameter and 16.5 ft perimeter loop, which may be a fraction of a wavelength (perhaps less than ⅛ of a wavelength).  FIG. 5  also depicts a circuit and devices used to tune and match the loop to a standard 50-ohm transmission line and transmitter. The transformer device  205  in this case has approximately a 64:1, 500:1 and 10,000:1 turns ratio, to produce radiation across the respective frequency ranges of 7 to 7.3 MHz, 3.5 to 4 MHz and 0.505 to 0.510 MHz. With 100 watts of power input, ranges of 25 miles (day or night) may be obtained, with a low angle radiation pattern in plane  200  as depicted in  FIG. 2 . With loop  202  mounted in a horizontal or vertical plane approximately 20 to 22 ft off earth ground radiation is as shown in  FIG. 2 . In all planes, when the loop was mounted relative to earth ground the received polarization was in the same plane. To observe the above-described pattern, a 3.5 ft diameter one turn loop with a balanced input gain of 100 from a pre-amp circuit device and receiver was used.  FIG. 6  depicts circuit and devices used to tune and match loops to a standard 50-ohm transmission line and transmitter. 
       FIG. 3  depicts a set of two less than ½ wavelength perimeter planar loops in a series circuit, coplanar arrangement and radiation symbols  201  depicting a low angle omnidirectional radiation pattern in plane  200 . Radiation may be produced as shown in  FIG. 3  and  FIG. 4  in the 7 to 7.3 MHz, 3.5 to 4 MHz and 0.505 to 0.510 MHz frequency ranges with 100 watts of power input, with ranges up to 25 miles. As with the single loop of  FIG. 2 , to observe the radiation pattern a 3.5 ft diameter single turn loop with balanced input gain of 100 from a pre-amp circuit device and receiver was used.  FIG. 6  depicts circuit devices and arrangement of devices used to produce  FIG. 3  radiation pattern over 7 to 7.3 MHz 3.5 to 4 MHz and 0.505 to 0.510 MHz frequency ranges.  FIG. 4  depicts a set of 5 less than ½ wavelength perimeter planar loops in a series circuit in a planar arrangement; radiation symbols  201  depict a low angle partly directional radiation pattern in plane  200 . 
     An unexpected result is observed when two more 12.5 ft perimeter loops of  FIG. 3  are combined: The measured real part radiation resistance increases to the real part radiation resistance expected for an equivalent of a 50 ft dipole or 25 ft monopole antenna with ideal ground with equal electrical length for the frequency of operation. This has been observed in the arrangements of both  FIG. 3  and  FIG. 4 , when (1) two additional co-planar loops were added to the arrangement of  FIG. 3  with same relationship and wired for lowest inductance, and (2) after five more loops (in plane  200 ) were added to  FIG. 4 ; the measured real part radiation load resistance increased non linearly for both  FIG. 3  and  FIG. 4  loop arrangements. The increased inductance was tuned out by capacitor device  209 . The measured effective radiated power was increased to that of a normal dipole or monopole antenna of the same electrical length. The radiation pattern of the individual loops remained the same planar low angle mostly omnidirectional. This suggests that adding loops in series may increase efficiency by increasing real part radiation resistance of the main loop and increasing the effective radiated power in the low angle plane. 
       FIGS. 5-8  illustrate the effect of adding planar loops, in accordance with embodiments of the disclosure.  FIG. 5  shows a single round loop  202  with leads, having a total electrical length slightly less than ⅛ wavelength. The loop set of  FIG. 6  has a length slightly less than ¼ wavelength total length with the two round  202  loop devices in series with leads. The loop set of  FIG. 7  is slightly longer than ½ wavelength with the four round  202  loop devices and leads in series. The loop set of  FIG. 8  loop set is 1 wavelength long with the eight round  202  loop devices and leads in series.  FIG. 5  loop and circuit include, as above, less than ⅛ wavelength loop with leads, variable tune capacitor  208 , transformer  205  and standard UHF coax connector  206 . The circuit of  FIG. 6  includes loops with less than ¼ wavelength, with leads, variable tune capacitor  209 , transformer  205  and standard UHF coax connector  206 . The circuits required are the same except capacitor  208  ( FIG. 5 ) must be capable of a higher maximum capacitance tune value than capacitor  209  ( FIG. 6 ) which needs to tune to a lower minimum value capacitance. 
     The turns ratio of the transformer in  FIG. 5  transformer is preferably higher than that in  FIG. 6  to match the lower real part of radiation resistance in the electrically shorter loop of  FIG. 5 . Comparing  FIG. 7  with  FIG. 6 , two circuit changes are made to tune the slightly longer than ½ wavelength sets of  FIG. 7  loops: The  208 / 209  variable capacitor devices of  FIG. 5  and  FIG. 6  are changed to a variable inductance device (variable inductor device  210  of  FIG. 7 ); and the transformer device  205  turns ratio of  FIG. 7  must also be decreased due to the increased real part resistance of the electrically longer total electrical length loop. 
     Another embodiment is shown in  FIG. 8 , where the planar loops and leads have a length of 1 wavelength, and only a 1:1 balun type transmission line transformer  205  is required to tune the loops to resonance. The arrangement of  FIG. 8  has been found to match transmitter power input devices of approximately 50 ohms, when such loads are connected to jack  206  with a less than 1.5 to 1 SWR ratio and when the total length of  FIG. 8  loop set is made to approximate a physical length of 936/(frequency in MHz) feet. 
     Without being bound by any theory of operation, the following observations are offered with respect to the embodiment of  FIG. 1 . A model to explain the load tune operation of a set of less than ½ wavelength loops in series is as follows: A length of transmission line, say open wire ladder line type, if shorted at one end and driven at the other end will act as a inductor or capacitor under two sets of conditions—if the physical length of line is increased and the frequency is held constant, or the line length is held constant and the frequency is varied. The results for the second set of conditions above are well known. As the frequency is increased from 0 frequency the reactance of a fixed length line will vary from inductive to real to capacitive to real and repeat. This case is well understood from transmission line theory. The case of increasing the length of a transmission line and holding the frequency constant also produces the same result; the reactance varies from current value for length to real to inductive or capacitive then to the next opposite type of reactance and repeats.  FIGS. 5-8  illustrate the case of increasing the length of a transmission line holding frequency constant. A general high loss inside out transmission line model covering loop antennas and antennas made up of loop sets in series can be developed. 
     An advantage of tuning by electrical length to natural resonance without using variable inductor or variable capacitor devices is the loop sets of binary electrical length elements can be switched in or out of a series circuit and bypassed at a very fast rate (switching on the order of milliseconds). At a great distance, using low cost relays as shown in  FIG. 1 , the loop length can be set to get correct conditions for matched operation with 1:1 balun by switching in sets of planar coplanar and combined planar coplanar loop sets. This permits a common interface and eliminates all analog feedback control circuits and slow anti-backlash gear drives used with motor driven variable capacitors and variable coils. Another advantage is the range of this system is effectively 65000:1, which exceeds the range available from existing variable capacitors or variable coils. Another advantage is higher efficiency; the voltages across all antenna element loop sets is the same as the voltage across the coaxial cable for any given power level. Furthermore, when series variable capacitors or variable inductors are used to bring a less than or greater than one wavelength loop to resonance, the voltage across the loop is increased; the current times the reactance at frequency of the reactive elements causes this voltage. This reactive voltage is effectively added to the driving voltage from coaxial input, increasing the voltage across the loop and its elements. The heating effects of this increased voltage potential across the antenna and components is a cause of heating and this infrared heat energy loss reduces the useful radiation effective radiated power (ERP) of the antenna. 
       FIGS. 9-13  illustrate additional arrangements of planar and coplanar loops, in accordance with embodiments of the disclosure. It has been found that loop element spacing and loop spacing in all planes may control polarization and radiation angle and velocity factor of a loop set antenna. For this work the term “wide spaced,” when applied to individual loops, loop sets and loop element spacing, is defined as follows: The total physical series length of the loop in ft (or a section of a loop element spacing with physical length in ft) when multiplied by 0.384 micro henry/ft., corresponds to the universal permeability constant 1.26×10 −6  henry/meter converted to 0.384 micro henry/ft. If the measured inductance (measured at a frequency low enough to avoid natural resonance; 10 kHz or 100 kHz are typically used) within (plus or minus) 10 percent of the above calculated inductance, then the individual loop sets or section of loop element spacing is wide spaced. The radiation from such an arrangement will be in the plane  200  as depicted in  FIG. 2 ,  FIG. 3 ,  FIG. 4 ,  FIG. 9  and  FIG. 10 . For example, if the loop element is a 128 ft physically long wire making up a planar square loop such as  FIG. 9 , or four series connected planar loops as in  FIG. 10 , and the measured inductance is within approximately 10 percent of the calculated 49.1 micro henry, the loop or loop set is wide spaced and most radiation will be in plane  200 . 
       FIG. 11  shows a planar loop set physically 100 ft long made of four rectangular loops, each 10 ft long, on sides constructed using number 14 stranded 600 volt wire. With wire insulation in contact on sides of wires the measured inductance is 8.37 micro henry with “Q” of 7.84 at a test frequency of 100 kHz. (The “Q” or quality factor value is defined as the dimensionless ratio of energy stored in a system or component to the energy lost over a sine wave cycle at a frequency.) The measured value of inductance of 8.37 micro henry is outside the plus or minus 10 percent value range of the calculated 38.4 micro Henry value. This then is a case of closely spaced loops, this arrangement will produce mostly all angle isotropic radiation relative to plane  200 . 
       FIG. 12  depicts two of the  FIG. 9  100 ft physical length loops in a co-planar arrangement. Inductance measurements made by connecting the loops in series with connection for lowest inductance and “Q” indicate that a coplanar spacing of approximately 10 inches has no measurable effect on polarization and the wide space case is indicated by inductance measurement. With coplanar spacing less than 2.5 inch, the 10 percent point to zero spacing (zero spacing defined as wires close enough to have insulation touching) inductance measurements indicate the close spacing case and all angle isotropic radiation.  FIG. 13  shows two of the  FIG. 11  close spaced planar series loop sets used to empirically check the coplanar and planar narrow spaced case. When these loop sets are connected for lowest “Q” and inductance the radiation observed is all angle isotropic relative to plane  200 . The fact that the spacing of loops and loop elements affects polarization is important to the design and development of embodiments of this disclosure. The  FIG. 1  switching arrangement and the use with it of binary length radiating elements makes it possible to select the best path set length. 
       FIG. 14  depicts two four loop, planar loop sets in a coplanar combination in a series circuit connection, in accordance with another embodiment. The loop arrangement of  FIG. 14  may optionally be used with three thin metal plates  300 . These energy guide plates  300  are placed as depicted below in  FIG. 14  and  FIG. 15  in the middle and on top of the two planar loop sets as depicted in  FIG. 15  (which is a side view of  FIG. 14 ). The energy guide plates are insulated from the loop wire and each other. The use of these plates is to convert the all angle isotropic energy produced by close spaced loops into low angle omni-directional radiation shown by  FIG. 16  (a top view of  FIG. 14  and  FIG. 15 ). If all angle isotropic radiation is desirable the energy guide plates can be eliminated.  FIG. 17  depicts a flat wire binary length set, of three planar loops having lengths of 1 ft, 2 ft, and 4 ft.  FIG. 18  also depicts a flat circuit board (possibly a printed wire board or board with stamped sheet metal) with a flat binary length set of three planar loops 1 ft, 2 ft, and 4 ft in length.  FIG. 19  from left to right depicts a partial assembly of a stack  407  (shown assembled in  FIG. 21 ) of combined planar and coplanar loop sets. Moving from left to right a 1 ft 1 inch energy guide plate or foil  400  is depicted. Next a square insulator  401 , 1 ft four inches square insulator made from ⅛-inch thick plywood or Plexiglas or other suitable plastic. Next  402  depicts a 64 ft total length, 1 ft by 1 ft flat planar wire loop set made of folded number 14 solid or stranded 600 volt insulated wire. Next,  403  depicts a 1 ft 4 inch square cavity insulator made of plywood, Plexiglas or other suitable plastic, with wire holes  403  and a 1 ft square cavity in the center. Next,  401  is an insulator 1 ft four inches square made as  403  above. Next device  400  is an energy guide plate made as  400  above. Next  401  insulator is made same as  401  above. Next in  FIG. 19 ,  402  depicts a 64 ft planar loop half of a 128 ft total loop set. Finally,  403  (cavity insulator) and  401  (insulator) complete the partial assembly illustration sequence. 
     Referring now to  FIG. 21 , this figure depicts planar loops in a stack with connection to relays  409  mounted in sockets on circuit board  411 , mounted on base plate  405  with two of four mounting legs  406  of base assembly. Operation is as described for the  FIG. 1  embodiment except the acceding binary length planar loop sets are stacked as shown in  FIG. 19  and  FIG. 21  stack  407 . In addition, in this miniature version the three way connectors of  FIG. 1  are eliminated and stacked loops and loop sets are connected to switch relay or other switch device by circuit board  405  mounted on base plate side view  FIG. 21 . 
     The use of devices embodying the disclosure to produce low angle omni directional radiation with energy guide plates is depicted in  FIG. 23 ,  FIG. 15  and  FIG. 16 . Devices using all angle isotropic radiation are depicted in  FIG. 22  and  FIG. 24 .  FIG. 20  depicts a top view of cover  404  installed on circuit board  405  base plate assembly.  FIG. 21  depicts a miniature device with a radio frequency transparent cover  404  removed; stack  407  of insulated loops  408 , some of the wires connecting stacked planar loops to printed  409  three of 9 relays or other switch devices performing the same function for a 1.8 to 30 MHz miniature embodiment. The balun device  410  can be a 1:1 transformer device,  411  circuit board  405  base plate 10 relays or other switching device assemblies that provide for the same function. Also the stacked planar loops with the above described assembly method, whose lengths with leads are 1 ft, 2 ft, 4 ft, 8 ft, 16 ft, 32 ft, 64 ft, 128 ft, 256 ft, 512 ft. These loop sets are wired to switch devices, as shown in ascending order in  FIG. 1 , and form the low profile 5 inch by 1.4 ft square loop set stack of  FIG. 21 . 
     Referring again to  FIG. 1 , in an additional embodiment an antenna system uses switched dipole antennas having lengths given by a binary sequence. A switching method is used in this embodiment where less than ½ wavelength dipole antennas are used as ascending binary length radiating elements in place of the ascending binary length loop or loop set radiating elements  31 - 46  of  FIG. 1 . For example, loop  31  across terminals  71 ,  72  in  FIG. 1  is replaced with a transmission line balun device of the construction disclosed for  30 . One side of this transmission line balun is connected across  71 ,  72 . The other side of the balun is connected to one end of a coax cable electrically 2 ft long. The other end of this coax cable is connected to one side of a second balun identical to the first  30  device. This second balun device two output leads are then connected to the center of a dipole. Each side dipole wires are each six electrical inches long. Loop  32  across  73 , 74  is next replaced with a transmission line balun device of the construction disclosed for  30 . One side of this transmission line balun is connected across  73 ,  74 . The other side of balun is connected to one end of a coax cable electrically 4 ft long. The other end of this coax cable is connected to one side of a second balun identical to the first device  30 . This second balun device two output leads are then connected to the center of a dipole. Each side dipole wires are each 1 ft electrical length long. The above procedure can be used to work out all values required to change  FIG. 1  embodiment from loops or loop sets to dipoles. This embodiment is desirable in the HF frequency range to microwave frequency ranges. 
     In another embodiment, a switching method as in  FIG. 1  is used with less than ½ wavelength monopole antennas. The monopole antennas, each with individual or common ground planes equal to monopole height in radius, are used as ascending binary length radiating elements in place of the ascending binary length loop or loop set radiating elements  31 - 46  of  FIG. 1 . For example, loop  31  across terminals  71 , 72  is replaced with a transmission line balun device of the construction disclosed for  30 . One side of this transmission line balun is connected across terminals  71 ,  72 . The other side of balun is connected to one end of a coax cable electrically 2 ft long. The other end of this coax cable is connected to one side of a second balun identical to the first  30  device. This second balun device has two output leads; one lead is connected to monopole, the other lead to ground plane. The monopole wire is six electrical inches in height. Loop  32  across terminals  73 , 74  is next replaced with a transmission line balun device of the construction disclosed for  30 . One side of this transmission line balun is connected across terminals  73 ,  74 . The other side of balun is connected to one end of a coax cable electrically 4 ft long. The other end of this coax cable is connected to one side of a second balun identical to the first device  30 . This second balun device has two output leads; one lead is connected to monopole ground plane, the other to monopole wire. The monopole wire is 1 electrical ft in height. This procedure can be used to work out all values required to change  FIG. 1  embodiment from loops or loop sets to monopole radiators. This embodiment is most practical from the HF frequency range to microwave frequency ranges 
     An additional low pass shifted harmonic resonance with binary value switched inductors embodiment under development is disclosed. Transmitting devices sometimes have harmonic energy in their output signals. The natural resonant  2 ,  3 ,  4  harmonics of arrangements such as in  FIG. 1  can radiate transmitter and other harmonics. It has been theorized and empirically proven that four or more inductor devices can be used with the basic switching arrangement of  FIG. 1 , to un-bypass and connect and disconnect and bypass inductor devices in the same manner of  FIG. 1  with loop, loop set or other binary length radiators. The correct inductance values for inductors was calculated by finding the equivalent inductance value for 8 ft, 4 ft, 2 ft and 1 ft wide spaced loops using the universal permeability constant (1.26×10 −6  henry/meter) converted to 0.384 micro henry/ft. The four respective switched inductor values are 3.072 microhenry, 1.536 microhenry, 0.768 microhenry and 0.384 microhenry. In operation with the coil devices the loop is set to a length of just less than 1 wavelength and the binary coil set is switched to a value to cancel the capacitive reactance of the main loop produced by the length less than one wavelength setting. This type of operation results in the antennas natural resonate frequency series 2, 3, 4, 5 harmonic radiating series being shifted off the operating frequency of the transmitter and the effective suppression of its 2, 3, 4, 5 harmonic series. Most modem transmitters and amplifier devices have filters to prevent and suppress harmonics. The above low pass shifted harmonic resonance using binary switched inductor devices embodiment will be of most use when active devices are used to replace the electromechanical switches of  FIG. 1 . Active devices in this case include such devices or arrangements of devices as, solid state diode, transistor devices, thermionic, gas tube or other types of active devices. All active devices are nonlinear over parts of their ranges when clean of harmonic energy signals from modern transmitters and amplifiers is switched through such devices a harmonic series of signals will be generated shifting the antenna harmonic series of the fundamental frequency will suppress low pass filter such harmonics. The use of active elements will permit the antenna tuned resonant frequency to be shifted under very high-speed conditions for some applications of invention. Shifting of the harmonic series using a set of binary value switch capacitor devices is also a possibility for some applications probably receive only versions or low power portable light weight transmit versions of the antenna. 
     Other additional embodiments include an interface to a frequency counter module for a computer to read frequency and remember settings and software to map setting for all bands and auto switch antenna. A relay under software control to disable transmitter to amplifier keying PTT (push to talk) and or relay with voltage to ALC (automatic level control) line of amplifier to reduce power during tuning. 
       FIGS. 22 to 25  depict some typical applications for miniature close spaced low profile embodiments of the disclosure. 
     An alternative 24 volt 60 cycle AC relay device that has been used in place of the sixteen 12 volt DC relays described above for relays  51 - 66  is the type “Tyco Electronics Potter &amp; Brumfield” (Philadelphia, Pa.), and are type ”PRD-11AGO-24 24 volt 50.60 HZ DPDT TYPE 10 amp, 600 volt rated contacts.” The 12 VDC source  20  must be replaced by a 24 volt transformer; all other above-described control operations are the same as described but at 24 VAC. 
     Again referring to  FIG. 1 , and coax UHF type panel jack  28 : A coaxial type lightning arrestor device required by electrical code for outside use with a direct to earth ground should be installed. This lightning safety earth ground is not used for transmitting or receiving by antenna. 
     The type of conductor used to construct the radiating loops is determined by structural and RF power level of operation. Individual loops of inside parameter and leads less than ½ wavelength have been made and combined into loop sets of various loop shapes from conductors such as IDC Type 3M3625 SERIES 1.0 MM ROUND CONDUCTOR FLAT CABLE 3M PART NO. 3625/50 ribbon wire. In this case all fifty of the individual number 28 stranded wire conductors are connected in parallel at each end. Copper strips as well as aluminum strips, copper, foil strips, copper tube, aluminum tube, #14 stranded wire, solid wire and many mixed conductors may be used to construct binary length loop sets. 
     Loop shapes including square, round and rectangular loops have been tested and found to perform as described above; accordingly, a wide variety of freestanding structures are possible where loops and insulating structural members are combined to form freestanding remote tunable structures. 
     In alternative embodiments, other components may be used to perform the functions of the various devices shown in  FIG. 1 . For example, the direct substitution of individual solid state devices for  FIG. 1  electromechanical relay devices to accomplish the same switch function; the substitution of other types of electromechanical or other switch devices performing the same switch function as  FIG. 1  relay devices; and the substitution of any solid state devices and other components, such as transformers, diodes, transistors, resistors, capacitors, inductors in any and all circuit combinations to perform the function of the  FIG. 1  electromechanical relay devices. An embodiment has been described with reference to  FIG. 1 , with loop set lengths required for binary operation and manual control switch box that can be used to operate the antenna under manual control. It will be appreciated that it is often preferred to operate the antenna system remotely and/or under computer automatic control. Arrangements including the relay switching device and loop sets of  FIG. 1 , and including automatic remote control, are described below. 
       FIG. 26  illustrates an antenna system according to a further embodiment of the disclosure, and including the relay switching device and radiating elements described in  FIG. 1 . Block  500  indicates a standard shielded transmitter device with signal frequency F o  of type function K sin(2 π F o  t+0) voltage source, with an internal series resistance of 50 ohms. UHF type coaxial jack  501  connects by coaxial cable with UHF type coaxial plug  502  to balun device  505  by 50 ohm coaxial cable through UHF type coaxial plug  503  to balun device UHF type coaxial jack  504 . Balun device  505  connects to standing wave ratio (SWR) detector device  506 , which is connected to remote indicator device  513  by monitor wiring buss  514 . Device  507  is the relay switching device as described with reference to  FIG. 1 , and used to set antenna electrical length by switching by remote control; Remote control  515  connects to relay switching device  507  via wire buss  516 . As described above, planar or co-planar series connected antenna loop sets of binary length 1, 2, 4, 8, 16,3 2, 64, 128, 256 etc. are switched in and out; five of the typical ten sets of planar loops are indicated at  508 - 512 . 
       FIG. 27  illustrates another antenna system with some features similar to  FIG. 26 . As in  FIG. 26 , block  520  depicts a standard shielded transmitter device with signal frequency F o  of type function K sin(2 π F o  t+0) voltage source, with internal series resistance of 50 ohms. UHF type coaxial jack  521  connects by coaxial cable with UHF type coaxial plug  522  to balun device  525  through UHF type coaxial plug  523  to balun UHF type coaxial jack  524 . Balun device  525  connects to standing wave ratio (SWR) detector device  532 , which is connected to remote indicator device  533  by monitor wiring buss  534 . Device  526  is the relay switching device as described with reference to  FIG. 1 , and used to set antenna electrical length by switching by remote control. Remote control  536  connects to device  526  by wire buss  538 . Planar or co-planar series connected antenna loop sets of binary length 1, 2, 4, 8, 16, 32, 64, 128, 256 etc. are switched in and out as described with reference to  FIG. 1 . Five of the typical ten sets of planar loops are shown at  527 - 531 . Device  539  is a remote controlled variable inductance device in series with SWR detector device  532  and relay switching device  526 . The remote control  535  for device  539  is connected by buss cable  537 . 
       FIG. 28  illustrates a further development of the antenna system with some features similar to  FIG. 27 . Block  540  depicts a standard shielded transmitter device with signal frequency F o  of type function K sin(2 π F o  t+0) voltage source, with internal series resistance of 50 ohms. Output UHF type coaxial jack  541  connects by coaxial cable  543  with UHF type coaxial plug  542  to balun device  546 , via UHF type coaxial plug  544  to balun UHF type coaxial jack  545 . Balun device  546  connects to SWR detector device  547 , which is connected to remote indicator device  554  by monitor wiring buss  555 . SWR detector device  547  is connected in series with devices  565 ,  566 ,  563 , each of which are connected to respective remote control and indicator devices  556 ,  558 ,  560  by buss cables  557 ,  559 ,  561 . Device  565  is a remote controlled capacitor device, and device  566  is a remote controlled variable inductance device. Device  563  is connected in series with relay switching device  548 , used to set antenna electrical length by switching by remote control  562 , connected by wire buss  564 . Planar or co-planar series connected antenna loop sets of binary length 1, 2, 4, 8, 16, 32, 64, 128, 256 etc. length are switched in and out as described with reference to  FIG. 1 . Five of the typical ten sets of planar loops are shown at  549 - 553 . 
       FIG. 29  illustrates an antenna system according to an embodiment of the disclosure, with features similar to those in  FIGS. 26-28 . Block  570  depicts a standard shielded transmitter device with signal frequency F o  of type function K sin(2 π F o  t+0) voltage source, with internal series resistance of 50 ohms. Output UHF type coaxial jack  571  connects by 50 ohm coaxial cable with UHF type coaxial plug  572 , and by 50 ohm coaxial cable to UHF type coaxial plug  573  and UHF type coaxial jack  574  to balun device  575 . Balun device  575  connects to SWR detector device  578 , which is connected to remote indicator device  579  by monitor wiring buss  580 . SWR detector device  578  is connected in series with device  581  (a variable capacitor device mechanically ganged to capacitor device  582  by a insulated shaft such that both devices are set to the same capacitance value). A variable inductance device  585  is connected across capacitor devices  581 ,  582 . A variable capacitor device  583  is connected between the junction of  584  and  585  in series to device  586 , which is a relay switching device described above with reference to  FIG. 1 . Variable capacitor device  584  is connected between the junction of  581  and  585  in series to device  586 . Variable capacitor device  583  is mechanically ganged to capacitor device  584  by a insulated shaft such that both devices are set to the same capacitance value. Relay switching device  586  is used to set antenna electrical length by switching by remote control. Remote control  592  is connected to device  586  by wire buss  593 . Planar or co-planar series connected antenna loop sets of binary length 1, 2, 4, 8, 16, 32, 64, 128, 256 etc. are switched in and out as described for  FIG. 1  operation. Five of the typical ten planar loop sets are shown at  587 - 591 . The circuit shown in  FIG. 29  is a twin “T” balanced matching network connected from the two output leads of SWR detector  578  to relay switching device  586  used to set antenna electrical length. 
       FIG. 30  illustrates an antenna system with some features similar to  FIGS. 26-29 . Block  600  depicts a standard shielded transmitter device with signal frequency F o  of type function K sin(2 π F o  t+0) voltage source, with internal series resistance of 50 ohms. Output UHF type coaxial jack  601  connects by coaxial cable through UHF type coaxial plug  602  to balun device  605 , by UHF type coaxial plug  603  to balun UHF type coaxial jack  604 . Balun device  605  connects to SWR detector device  606 , which is connected to remote indicator device  607  by monitor wiring buss  608 . SWR detector device  606  connects in series with fixed value capacitor  610 , fixed value capacitor  612 , and relay switching device  614  (described above with reference to  FIG. 1 ). 
     As shown in  FIG. 30 , SWR detector device  606  is also connected in series with fixed value capacitor  611  and fixed value capacitor  613 , which connects to relay switching device  614 . Device  614  is used to set antenna electrical length by switching by remote control. Remote control  622  is connected to device  614  by wire buss  623 . Planar or co-planar series connected antenna loop sets of binary length 1, 2, 4, 8, 16, 32, 64, 128, 256 etc. are switched in and out as described with reference to  FIG. 1 . Five of the typical ten planar loop sets are shown at  615 - 619 . 
     Remote controlled variable binary value switched inductor device  609  is connected from the junction of devices  610 ,  612  to the junction of devices  611 ,  613  to form a twin “T” balanced matching network, where the antenna electrical length is set by device  614  to ⅝ to ⅞ wavelength and resonance of the network is set by binary value switched inductance device  609 . Device  609  is controlled by a remote device  620 , connected to device  609  by wire buss  621 . 
     A specific embodiment, as shown schematically in  FIG. 30 , has been constructed as follows: 
     Fixed capacitor device  612  is made up from two fixed value 2 pf 25,000 volt DC vacuum capacitor devices in series to form a 1 pf 50,000 volt DC device. 
     Fixed capacitor device  613  is made up from two fixed value 2 pf 25,000 volt DC vacuum capacitor devices in series to form a 1 pf 50,000 volt DC device. 
     Fixed capacitor device  610  is one 300 pf 25,000 volt DC vacuum capacitor device. 
     Fixed capacitor device  611  is one 300 pf 25,000 volt DC vacuum capacitor device. 
     Remote controlled variable inductor device  609  is made of air coil inductor devices switched in out and bypassed by relays. 
     The total inductance value is 512 micro henrys. This device uses inductor values; 256 micro henrys, 128 micro henrys, 64 micro henrys, 32 micro henrys, 16 micro henrys, 8 micro henrys, 4 micro henrys, 2 micro henrys, 1 micro henry. 
     The coplanar loop sets are constructed in the form of  FIGS. 17 and 19  in a stack such as shown in  FIG. 21 , with parallel series loop wires spaced 0.5 inch and 12 inches long. Referring to  FIG. 19 , number 10 stranded 600 volt wire  402  was stapled onto ⅛ thick spacer board  401 , then a cavity spacer board  403 , ⅛ inch thick, was placed over wire; the next ⅛ inch spacer board  401  provides an approximate 0.5 inch space between coplanar loop sets. 
     An antenna system according to the disclosure offers important advantages in that it is both compact and tunable. Referring again to the antenna system shown in  FIG. 30 , and without being bound by any theory of operation, suppose that the transmitter AC voltage from transmitter section  600  is given by 
         v ( t )= K  sin(2  π F   o    t ) 
     where F o  is the transmitter frequency. The peak voltage K may be evaluated from the RMS power input to the transmitter, and the transmitter series resistance R. The antenna may be tuned, using relay switching device  614 , so that the antenna electrical length is less than or equal to one wavelength at F o . The input current as a function of time is 
         i ( t )= v ( t )/ R=K  sin(2  π F   o    t )/ R    
     and the power input 
         p ( t )= i ( t ) 2   R=K   2  sin 2 (2  π F   o    t )/ R    
     The energy input forcing function j(t)=d/dt p(t) 
         j ( t )=2 K   2  sin(2  π F   o    t ) cos(2 π F   o    t ) 2 π F   o   /R =(2 π F   o    K   2   /R ) sin(4 π F   o    t ) 
     and the total energy input over one RF cycle 
         E=∫p ( t )  dt=K   2 /2 RF   o    
     and applying conservation of energy, 
     
       
      
       E=|IR|+|RF| 
      
     
     where IR and RF represent infrared energy radiation and radio frequency energy radiation, respectively, and |x| denotes absolute value or magnitude: |x|=sqrt(x 2 ). 
     The RF energy into the antenna at the frequency of operation F o  is split and converted by the antenna into radiated IR heat energy and radiated RF energy according to the ratio of the antenna wire physical length to the radiation wavelength: 
     antenna wire physical length=x 
     radiation wavelength=λ 
         E =|(1−( x /λ)) E |+|( x /λ) E|   
     where the first term is the IR heat radiation term and the second term is the RF radiation term. The balance between IR and RF radiation thus depends on the antenna length relative to the wavelength of radiation. If the antenna total physical length is ½ the wavelength, IR radiation equals RF radiation. If the antenna total physical length is much less than the wavelength, nearly all the radiation is IR heat radiation. If the antenna total physical length is equal to the wavelength, nearly all the radiation is RF radio frequency radiation. This has been observed for the long electrical length, folded conductor antennas described herein, despite the compactness of the overall system. Antenna systems embodying the present disclosure therefore offer significant practical advantages. 
     While the disclosure has been described in terms of specific embodiments, it is evident in view of the foregoing description that numerous alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the disclosure is intended to encompass all such alternatives, modifications and variations which fall within the scope and spirit of the disclosure and the following claims.