US3699452A - Active antenna arrangement for a plurality of frequency ranges - Google Patents

Active antenna arrangement for a plurality of frequency ranges Download PDF

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Publication number
US3699452A
US3699452A US11569A US3699452DA US3699452A US 3699452 A US3699452 A US 3699452A US 11569 A US11569 A US 11569A US 3699452D A US3699452D A US 3699452DA US 3699452 A US3699452 A US 3699452A
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US
United States
Prior art keywords
set forth
active antenna
antenna
frequency band
amplifier
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US11569A
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English (en)
Inventor
Heinz Lindenmeier
Hans-Heinrich Meinke
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Hans Kolbe and Co
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Hans Kolbe and Co
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Publication of US3699452A publication Critical patent/US3699452A/en
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/16—Circuits
    • H04B1/18—Input circuits, e.g. for coupling to an antenna or a transmission line
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/27—Adaptation for use in or on movable bodies
    • H01Q1/32—Adaptation for use in or on road or rail vehicles
    • H01Q1/325—Adaptation for use in or on road or rail vehicles characterised by the location of the antenna on the vehicle
    • H01Q1/3266—Adaptation for use in or on road or rail vehicles characterised by the location of the antenna on the vehicle using the mirror of the vehicle
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q23/00—Antennas with active circuits or circuit elements integrated within them or attached to them
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
    • H01Q5/30—Arrangements for providing operation on different wavebands
    • H01Q5/307—Individual or coupled radiating elements, each element being fed in an unspecified way
    • H01Q5/314—Individual or coupled radiating elements, each element being fed in an unspecified way using frequency dependent circuits or components, e.g. trap circuits or capacitors
    • H01Q5/321—Individual or coupled radiating elements, each element being fed in an unspecified way using frequency dependent circuits or components, e.g. trap circuits or capacitors within a radiating element or between connected radiating elements

Definitions

  • the frequency ranges lie within the longwave, intermediate wave, shortwave and ultra shortwave regions, that is, between frequencies of 0.15 and H MHz a number of frequency ranges, with large gaps therebetween, exist.
  • Such short antennas tuned for the ultra shortwave region, represent only a small capacitive coupling to the electromagnetic field in the longwave, intermediate wave and shortwave regions.
  • Such antennas are almost exclusively energized by the electrical component of the electromagnetic field.
  • cables must be used interconnecting the antenna and the receiver, which represent a very small capacitive component, that is, cables, which do not have a well-defined characteristic impedance.
  • rod-like antennas which are generally employed in a telescopic arrangement in commercial vehicles, are constantly in danger of inadvertent damage.
  • active antenna Also presently known in the art, is a so-called active antenna, as disclosed in Belgian Patent No. 725,370, issued Feb. 14, 1969. It is disclosed in this patent that broadband matching may be achieved between the parts of the antenna receiving the electromagnetic energy and the receiver, or the receiver cable, by use of controllable, three-terminal active elements. These three-terminal, controllable active elements, preferably transistors, are used to make the signal to noise ratio an optimum. This type of matching is hereinafter called noise matching. Since active elements are used in these antenna arrangements with such noise matching, these antenna arrangements will hereinafter be called active antennas.
  • the active antennas described above, as disclosed in the Belgian patent, have a single signal transmission path between the antenna parts receiving the radiant energy and the antenna output, for all frequencies and frequency ranges to be received.
  • the active antennas disclosed in the Belgian patent still do not constitute an arrangement which eliminates all of the following drawbacks:
  • the present invention is an antenna arrangement for receiving radiant energy in a plurality of frequency ranges at an antenna input and furnishing corresponding antenna output signals to an antenna output. It comprises a plurality of passive impedance elements for receiving said radiant energy..lt further comprises active impedance means, and connecting means connecting said passive impedance elements and said active impedance means in such a manner that a signal transmission path having transmission characteristics independent of the transmission characteristics of all other signal transmission paths, is formed between said antenna input and said antenna output for each of said frequency ranges.
  • the active impedance means may be independently matched to the passive impedance elements.
  • the active impedance means may comprise a plurality of active impedance elements, each associated with one transmission path, and the operating point of each active impedance element may be adjusted independently. In this way, an optimum coupling to the electromagnetic field may be combined with an optimum coupling to a cable interconnecting antenna output to the receiver input, and, further, very small antennas may be used, thus decreasing the probability of damage.
  • Each signal transmission path with its associated active elements can be matched and adjusted to the corresponding frequency range, so that, in spite of large differences in the frequency ranges, a single antenna may be used for optimum reception in all of these different frequency ranges.
  • the frequency band to be received is divided into two frequency ranges and two signal transmission paths are provided between the antenna input and the antenna output.
  • Each path may have its appropriate matching and/or amplification.
  • the two frequency ranges to be received in a commercial vehicle namely the long, intermediate and shortwave region on the one hand, and the ultra shortwave region on the other hand, may each be received in an optimum manner.
  • each of the signal transmission paths may lead to a separate antenna output, thus permitting signals within the two separate frequency ranges to be separately transmitted to, for example, a separate receiver.
  • only the active element for the upper, for example the ultra shortwave frequency range, is matched to the passive impedance element on a noise-matching basis.
  • This embodiment is particularly suitable for commercial vehicle antennas functioning in widely-separated frequency regions. Very little equipment is required, and the mismatching in the lower frequency range is acceptable.
  • the active element for the upper frequency range is capacitively coupled to the passive impedance elements, which, in this embodiment, are part of both the first and second signal transmission path.
  • the capacitive coupling may be achieved via the shield of a coaxial conductor.
  • the above-mentioned coaxial conductor is a printed pseudo coaxial cable comprising a first, second and third conducting strip, the first and third conducting strip consisting outer conductors and the shield for the second, or inner conducting strip.
  • control electrode of each active element is connected to a choke.
  • the chokes are so designed that all frequencies not within the frequency range of the signal path with which the particular active element is associated, are blocked from said signal path. This type of connection will substantially eliminate coupling between the different signal paths and resulting noise.
  • an additional active element is connected in series with the active element associated with the signal transmission .path in the lower frequency range. This reduces the danger of non-linear distortion and results in signal amplification without corresponding noise amplification, thus improving the sensitivity of the antenna.
  • FIG. 1 is a diagrammatic view of the active antenna of this invention.
  • FIG. 2 is a schematic circuit diagram showing the active elements of an antenna in accordance with the present invention.
  • the embodiment shown in the drawing is a printed circuit, which is particularly suitable for placement into the mounting of a rear-view mirror in a commercial vehicle.
  • conducting strips 1 and 2 are printed as printed circuits on an insulating plate P. These strips serve as inductors.
  • These conducting strips in conjunction with a top-loading capacity 3, which may be embodied in a rear-view mirror and with the car body or other metallic ground plane, constitute the passive or receiving part of the antenna.
  • the capacity 3 may be varied within predetermined limits, that is as long as the mathematical product of the effective antenna height multiplied by this capacity remains unchanged.
  • Conducting strips 1 and 2 constitute the means for transforming the impedance of the parts of the antenna which receive the electromagnetic energy to a value which allows an optimum noise matching to the active impedance elements.
  • These active elements of the active antenna comprise, as will be described in more detail below, the transistors 4 and 5 in the circuit shown in FIG. 2.
  • the capacity 3 has a definite function both in the upper frequency range, for example the ultra shortwave region, as well as in the lower frequency range, for example the longwave region.
  • the capacity 3 together with the conducting strips 1 and 2 constitute the capacity of an oscillator circuit serving as input circuits; in the upper frequency region, that is in the longwave region, the capacity 3 constitutes the main antenna capacity.
  • the printed conducting strip 1 is continued as the printed inner conductor 7 of a pseudo coaxial cable, which consists of three substantially parallel conducting strips, 2 and 7.
  • the conducting strip 1 and the inner conductor 7 of the pseudo coaxial cable also serves as a connection between the capacity 3 and the active element used in the signal transmission path for the lower frequency range, namely transistor 4.
  • the outer conductor of the pseudo coaxial cable, that is the conducting strip 2 serves as partial inductivity of the input circuit for coupling the active element for the upper frequency region, that is transistor 5, to the receiving,
  • passive part of the antenna It further constitutes, together with the input impedance of transistor 4, a part of the transformation circuit for matching the receiving part of the antenna on a noise matching basis to the input impedance of the active impedance element for the upper frequency region, that is transistor 5.
  • connection from the conducting strip 2 of the pseudo "coaxial cable to transistor 5, is made via terminal 8 to the printed surface of a coupling capacitor 9 (FIG. 1) and then to terminal 10 (FIG. 1 and FIG. 2) over an additional capacitor 11 to the base of transistor 5.
  • the resistances 12 and 13 shown in FIG. 2 serve to set the operating point of transistor 5.
  • transistor 4 the active impedance element for the lower frequency range, with the receiving part of the antenna is made via terminal 14 connected to the inner conductor 7 to the terminal 15 (FIG. 2) and via a choke l6 and a resistance 17 to the base of transistor 4.
  • a diode 18, shown in FIG. 2 protects transistor 4, namely the transistor for the lower frequency range, from static charges.
  • an additional active element, or amplifier, such as transistor 6 may be connected in series to the active impedance element for the lower frequency range.
  • the cascade circuit of transistors 4 and 6 increases the amplification without a corresponding increase in noise, thus effectively improving the sensitivity of the antenna arrangement.
  • the resistance 30 in the emitter circuit of transistor 6 serves as a feedback resistance and serves to submerge interference resulting from intermodulation into the noise level.
  • the resistance 17 serves to flatten any possibly existing resonance curves.
  • the choke 16, in conjunction with the resistance 17, serves to decrease interference which may result from electrical equipment associated with the engine of a commercial vehicle, when the active antenna of this invention is used in such a vehicle.
  • Such electrical interference, generated by the abovementioned associated electrical equipment, is radiated into the receiving parts of the antenna and produced by mixing with higher frequencies.
  • Choke 20 together with capacitor 21 serve as a general filter for the input to transistor 4, while resistance 22 together with capacitor 23 blocks high frequency interference from the input to transistor 4.
  • This high frequency interference may, for example,-
  • Choke 25 and capacitor 26 serve to de-couple the output voltage of the lower frequency range from the output of transistor 5, which serves to amplify the voltages of the upper frequency range, that is the ultra shortwave region.
  • the output of transistor'6 for the lower frequency range, and the output of transistor 5 for the upper frequency range are both connected to the antenna output.
  • the connection between the antenna output and the receiving means may then be made, for example by a coaxial cable 29.
  • Capacitor 26 serves this function as well as the function mentioned above.
  • Capacitors 27 and 28 serve to supply bias voltages.
  • An integrated active antenna combination comprising a plurality of interconnected passive impedance elements jointly receiving energy in a first and second frequency band; first noise-matched amplifier means having a control electrode and an output circuit; second noise matched amplifier means having a control electrode and an output circuit; first coupling circuit means capacitively connected to said plurality of interconnected passive impedance elements for passing only frequencies in said first frequency band to said control electrode of said first amplifier means, while rejecting frequencies in said second frequency band; second coupling circuit means inductively connected to said interconnected passive impedance elements for passing only frequencies in said second frequency band to said control electrode of said second amplifier means, while rejecting said frequencies in said first frequency band; antenna output terminal means; and means connecting the output circuit of said first and second amplifier means to said antenna output terminal means, whereby said first coupling circuit means and first amplifier means constitute a first signal transmission path transmitting signals in said first frequency band only, and said second coupling circuit means and second amplifier means constitute a second signal transmission path passing frequencies in said second frequency band only.
  • Active antenna as set forth in claim 1, wherein said upper frequency range is in the ultra shortwave region.
  • said first amplifier means has a first and second output electrode and a control electrode further comprising means determining the operating point of said first amplifier means.
  • said means determining the operating point comprise a voltage source, voltage divider means having a voltage divider tap connected across said voltage source, and means connecting said control electrode to said voltage divider tap; and wherein the voltage at said voltage divider tap is a function of the frequencies in said first frequency band.
  • said antenna output terminal means comprise a first and second terminal respectively furnishing frequencies in said first and second frequency band.
  • said passive impedance elements comprise printed conducting strips; wherein said passive circuit means further comprise top-loading capacitor means; and wherein said first coupling circuit means comprise printed circuit capacitor means.
  • said passive impedance elements comprise pseudo-coaxial cable means having a first, second and third conducting strip, said first and third conducting strip being situated on either side of said second conducting strip; and wherein a printed circuit capacitor means is connected to said third conducting strip.
  • said second coupling circuit means comprise inductor means; and means connecting said inductor means to said second conducting strip.
  • Active antenna as set forth in claim 10, wherein said second amplifier means comprise emitter follower amplifier means.
  • Active antenna as set forth in claim 11, further comprising third amplifier means cascade-connected to said emitter-follower amplifier means.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Remote Sensing (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)
  • Details Of Aerials (AREA)
  • Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)
  • Amplifiers (AREA)
  • Noise Elimination (AREA)
US11569A 1969-04-18 1970-02-16 Active antenna arrangement for a plurality of frequency ranges Expired - Lifetime US3699452A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE1919749A DE1919749C3 (de) 1969-04-18 1969-04-18 Aktive Empfangsantenne mit Dipolcharakter

Publications (1)

Publication Number Publication Date
US3699452A true US3699452A (en) 1972-10-17

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Family Applications (1)

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US11569A Expired - Lifetime US3699452A (en) 1969-04-18 1970-02-16 Active antenna arrangement for a plurality of frequency ranges

Country Status (14)

Country Link
US (1) US3699452A (de)
JP (1) JPS5549444B1 (de)
AT (1) AT354521B (de)
BE (1) BE743971A (de)
CH (1) CH519253A (de)
DE (1) DE1919749C3 (de)
DK (1) DK137909B (de)
ES (1) ES375206A1 (de)
FR (1) FR2039253B1 (de)
GB (1) GB1296535A (de)
LU (1) LU60028A1 (de)
NL (1) NL173116C (de)
NO (1) NO134074C (de)
SE (1) SE351529B (de)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3827053A (en) * 1970-07-23 1974-07-30 E Willie Antenna with large capacitive termination and low noise input circuit
FR2425736A1 (fr) * 1978-05-09 1979-12-07 Communications Patents Ltd Agencement d'antennes
US4201988A (en) * 1979-03-05 1980-05-06 The United States Of America As Represented By The Secretary Of The Navy Wideband VHF antenna
US4243992A (en) * 1979-04-16 1981-01-06 The United States Of America As Represented By The Secretary Of The Navy Method and apparatus for fabricating a wideband whip antenna
US4559539A (en) * 1983-07-18 1985-12-17 American Electronic Laboratories, Inc. Spiral antenna deformed to receive another antenna
WO1991000626A1 (en) * 1989-06-27 1991-01-10 Crowe, Brian, John Rear view mirrors including radio aerials
EP1191557A2 (de) * 2000-09-12 2002-03-27 Robert Bosch Gmbh Integrierter einstellbarer Kondensator
US6393264B1 (en) * 1995-09-15 2002-05-21 Siemens Aktiengesellschaft Radio terminal apparatus
US20040113854A1 (en) * 2002-10-01 2004-06-17 Heinz Lindenmeier Active broad-band reception antenna with reception level regulation
US20060267138A1 (en) * 2005-05-30 2006-11-30 Semiconductor Energy Laboratory Co., Ltd. Semiconductor device

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2122341B1 (de) * 1971-01-21 1974-04-26 Radiotechnique Compelec
DE2115657C3 (de) * 1971-03-31 1983-12-22 Flachenecker, Gerhard, Prof. Dr.-Ing., 8012 Ottobrunn Aktive Unipol-Empfangsantenne
NL7901901A (nl) * 1978-03-10 1979-09-12 Blankenburg Antennen Antenne voor meerdere ontvangstgebieden met elektroni- sche versterker.
DE2952793C2 (de) * 1979-12-31 1983-04-28 Flachenecker, Gerhard, Prof. Dr.-Ing., 8012 Ottobrunn Abstimmbare Empfängereingangsschaltung
DE3315458A1 (de) * 1983-04-28 1984-11-08 Gerhard Prof. Dr.-Ing. 8012 Ottobrunn Flachenecker Aktive windschutzscheibenantenne fuer alle polarisationsarten
GB9114720D0 (en) * 1991-07-08 1991-08-28 Electronic Advanced Research L Radio receiving circuits

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1647474A (en) * 1923-10-25 1927-11-01 Frederick W Seymour Variable pathway
US2531438A (en) * 1947-03-21 1950-11-28 William J Jones Multiple distribution radio receiving system
US2578973A (en) * 1946-12-11 1951-12-18 Belmont Radio Corp Antenna array
US3465344A (en) * 1967-01-26 1969-09-02 Sylvania Electric Prod Single antenna dual frequency band signal coupling system

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT157792B (de) * 1934-11-15 1940-01-25 Hazeltine Corp Schaltung zur Kopplung zweier elektrischer Stromkreise.
US2169358A (en) * 1936-07-18 1939-08-15 Telefunken Gmbh Receiver for ultra-short waves
DE975147C (de) * 1950-02-22 1961-09-07 Siemens Elektrogeraete Gmbh Koppelvorrichtung zum gleichzeitigen Anschluss einer UKW-Antenne und einer Kurz-Mittel-Langwellenantenne an Hochfrequenzempfaenger fuer mehrere Wellenbereiche
US3424984A (en) * 1964-02-28 1969-01-28 Antenna Res Ass Directional broad band antenna array
NL6517121A (de) * 1965-12-30 1967-07-03
DE1272391B (de) * 1967-04-28 1968-07-11 Hirschmann Radiotechnik Anordnung zur Anschaltung mehrerer selektiver Antennenverstaerker an einen gemeinsamen Verbraucher

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1647474A (en) * 1923-10-25 1927-11-01 Frederick W Seymour Variable pathway
US2578973A (en) * 1946-12-11 1951-12-18 Belmont Radio Corp Antenna array
US2531438A (en) * 1947-03-21 1950-11-28 William J Jones Multiple distribution radio receiving system
US3465344A (en) * 1967-01-26 1969-09-02 Sylvania Electric Prod Single antenna dual frequency band signal coupling system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Mayes, Tiny Antennas Push State of Art , Electronics World; March, 1968; pp. 49 51 *

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3827053A (en) * 1970-07-23 1974-07-30 E Willie Antenna with large capacitive termination and low noise input circuit
FR2425736A1 (fr) * 1978-05-09 1979-12-07 Communications Patents Ltd Agencement d'antennes
US4201988A (en) * 1979-03-05 1980-05-06 The United States Of America As Represented By The Secretary Of The Navy Wideband VHF antenna
US4243992A (en) * 1979-04-16 1981-01-06 The United States Of America As Represented By The Secretary Of The Navy Method and apparatus for fabricating a wideband whip antenna
US4559539A (en) * 1983-07-18 1985-12-17 American Electronic Laboratories, Inc. Spiral antenna deformed to receive another antenna
WO1991000626A1 (en) * 1989-06-27 1991-01-10 Crowe, Brian, John Rear view mirrors including radio aerials
US6393264B1 (en) * 1995-09-15 2002-05-21 Siemens Aktiengesellschaft Radio terminal apparatus
EP1191557A2 (de) * 2000-09-12 2002-03-27 Robert Bosch Gmbh Integrierter einstellbarer Kondensator
EP1191557A3 (de) * 2000-09-12 2007-04-04 Robert Bosch Gmbh Integrierter einstellbarer Kondensator
US20040113854A1 (en) * 2002-10-01 2004-06-17 Heinz Lindenmeier Active broad-band reception antenna with reception level regulation
US6888508B2 (en) 2002-10-01 2005-05-03 Fuba Automotive Gmbh & Co. Kg Active broad-band reception antenna with reception level regulation
US20060267138A1 (en) * 2005-05-30 2006-11-30 Semiconductor Energy Laboratory Co., Ltd. Semiconductor device
US7688272B2 (en) * 2005-05-30 2010-03-30 Semiconductor Energy Laboratory Co., Ltd. Semiconductor device

Also Published As

Publication number Publication date
ES375206A1 (es) 1972-03-01
DE1919749B2 (de) 1973-07-19
AT354521B (de) 1979-01-10
DE1919749A1 (de) 1970-10-08
NL173116B (nl) 1983-07-01
BE743971A (de) 1970-05-28
DE1919749C3 (de) 1982-05-13
NL6919443A (de) 1970-10-20
FR2039253B1 (de) 1977-01-14
GB1296535A (de) 1972-11-15
DK137909B (da) 1978-05-29
NO134074C (de) 1976-08-11
SE351529B (de) 1972-11-27
LU60028A1 (de) 1970-02-16
JPS5549444B1 (de) 1980-12-12
NO134074B (de) 1976-05-03
NL173116C (nl) 1983-12-01
CH519253A (de) 1972-02-15
FR2039253A1 (de) 1971-01-15
ATA1206869A (de) 1977-10-15

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