US3803617A - High efficiency multifrequency feed - Google Patents
High efficiency multifrequency feed Download PDFInfo
- Publication number
- US3803617A US3803617A US00244158A US24415872A US3803617A US 3803617 A US3803617 A US 3803617A US 00244158 A US00244158 A US 00244158A US 24415872 A US24415872 A US 24415872A US 3803617 A US3803617 A US 3803617A
- Authority
- US
- United States
- Prior art keywords
- horn
- frequency band
- high efficiency
- feed system
- arms
- Prior art date
- 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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Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q25/00—Antennas or antenna systems providing at least two radiating patterns
- H01Q25/02—Antennas or antenna systems providing at least two radiating patterns providing sum and difference patterns
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
- G01S13/06—Systems determining position data of a target
- G01S13/42—Simultaneous measurement of distance and other co-ordinates
- G01S13/44—Monopulse radar, i.e. simultaneous lobing
- G01S13/4409—HF sub-systems particularly adapted therefor, e.g. circuits for signal combination
-
- 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
- H01Q5/40—Imbricated or interleaved structures; Combined or electromagnetically coupled arrangements, e.g. comprising two or more non-connected fed radiating elements
- H01Q5/45—Imbricated or interleaved structures; Combined or electromagnetically coupled arrangements, e.g. comprising two or more non-connected fed radiating elements using two or more feeds in association with a common reflecting, diffracting or refracting device
Definitions
- the apparatus of the present invention relates to antenna systems and particularly to compact and simple antenna feeds which can transmit and receive simultaneously in at least three frequency bands, each with high efficiency and polarization diversity.
- the feed system is especially applicable for frequency bands having nominal frequency bands with the ratio 1:416.
- satellite communications telemetry bands operate in frequency bands 0.8 1.0 GHZ, 3.7 4.2 GHz and 5.9 6.4 GHz.
- the antenna system of the invention has monopulse capability for reception with circular or diverse polarization at frequency band 1.
- PATENTEDAPR slam 3303517 SHEET 6 BF 7 P Fig.6. I f m r J 50 v sl v 52 Two Poinf Fed Dipole Model Showing Currenr Disirlbuiion 369 @FEZIFigT.
- the crossed dipole is not a conventional dipole in that each dipole is excited at two points with edges of a 6/4 GHz horn. as the central portion of the dipole.
- the primary pattern of the feed must illuminate the reflector or lens without an undue amount of spillover or without being too directive so as to under illuminate the reflector or lens.
- the net result is that the feed pattern for all three frequency bands must be nearly identical in all planes and have a common center of phase.
- One or more quarter wavechokes surrounding the 6/4 GHz horn aperture prevent coupling to the 1 GHz frequency wave dipole.
- a choke is built into the dipole wings to further prevent coupling with 4 GHz frequencies.
- the 6 GHz frequencies are sufficiently far removed from the 1 GHz frequency band so that the coupling to the l GHz dipole is sufficiently suppressed by the choke around the horn alone. Separation between the 6 GHz and 4 GHz frequencies is achieved with conventional diplexers.
- the two feed points of the dual feedpoint dipole are connected with a hybrid (e.g., a magic tee). When the difference port is used, the currents in the dipole wings are in phase resulting in a good sum" pattern.
- the sum port of the hybrid When the sum port of the hybrid is used, the currents in the dipole wings are in anti-phase creating a null pattern. Hence, for certain polarizations, the sum port of the hybrid can be used for monopulse tracking applications. This type of tracking is especially applicable in circularly polarized systems.
- FIG. 1 shows a plan view of a C band UHF aperture of a high efficiency multifrequency feed in accordance with the present invention
- FIG. 2 shows a cross-sectional view of the C Band UHF aperture of FIG. 1;
- FIGS. 3-5 illustrate the feed patterns'for the H, E and diagonal planes for each of the frequency bands of the apparatus of FIGS. 1 and 2;
- FIG. 6 illustrates a schematic of a two point pole model showing current distribution
- FIG. 7 illustrates a schematic showing the manner in which a higher frequency horn feed serves as a central portion of the two point fed dipole in the illustration of FIG. 6;
- FIG. 8 illustrates the manner in which the two point fed dipole of FIG. 7 is fed by the use of a 4-Pont Hybrid
- FIGS. 9-l2 show alternative configurations of the plan view of the aperture of the multifrequency feed of FIGS. 1 and 2.
- FIGS. 1 and 2 of the drawings there is shown a plan view of the aperture and a cross-section 22 thereof, respectively, of the high efficiency multifrequency feed antenna system of the present invention.
- a square horn 10 having dimensions suitable to provide a 6 GHz and 4 GHz common aperture extends through the central portion of a conductive ground plane 12.
- the square horn 10 On the back side of ground plane 12 relative to the antenna aperture, the square horn 10 extends into a multimode step section 14 dimensioned for 6 GHz which section 14 terminates in a flange 15.
- the multimode step section 14 is symmetrically disposed about the center line through horn l0.
- a choke section 16 Surrounding the outer periphery of horn 10 at the lip thereof is disposed a choke section 16 primarily designed to inhibit the flow of 4 GHz energy thereacross.
- a dielectric disc 18 extends radialy outwards from the outer lip of choke section 16 for a sufficient distance to support UHF choked dipole arms 20, 21, 22 and 23 which extend outwards from the center of the four sides of horn 10.
- the outer periphery of dielectric disc 18 is supported by metallic posts 24 which extend to the ground plane 12.
- a UHF cavity is formed by metal bands 26, 28 disposed about the central portion and adjacent ground plane 12, respectively, of the metallic posts 24.
- the extremity of the center leg of the UHF choked dipole arms 20-23 nearest horn 10 are fed by the respective center conductors of coaxial lines 30-33, respectively.
- the coaxial lines 3033 extend through the ground plane 12 parallel to the center line of horn 10 and are terminated by connectors 34-37, respectively.
- the outer conductors of coaxial lines 30-33 are electrically connected to the outer periphery of choke section 16 and to the ground plane 12.
- a metal cylinder 40 terminating in a flange 42 is disposed symmetrically about metallic posts 24.
- Metal cylinder 40 is attached to ground plane 12 and has a height slightly greater than the dimension of square horn 10 which extends through the ground plane 12.
- the flange 42 provides a support for a radome if desired.
- the 4 GHz and 6 GHz frequency band signals are fed through the multimode step section 14 to the horn 10.
- Contemporary multimoding techniques are employed to obtain the mu ltimoding at the 6 G Hz frequency band and single moding at the 4 GHz frequency band.
- the mode exciters coupled to flange 15 are designed for both the 4 GHz and 6 GHz frequency bands and the common aperture of horn is dimensioned to be below cutoff for the higher modes at 4 GI-lz.
- the separation of the 4 GHz and 6 GHz frequency bands is achieved with conventional diplexers, not shown.
- Quarter wave choke 16 surrounding the 6/4 GI-Iz horn 10 aperture prevents coupling from the 4 GHz and 6 GHz frequency bands to the 1 GHz frequency dipoles 20-23. Also, there is a choke built into each ofthe dipoles 20-23 to further prevent coupling with the 4 GI-Iz frequencies. The 6 GHz frequencies are sufficiently far removed that coupling to the 4 GHz dipoles 20-23 is suf ficiently suppressed by the choke 16 around the horn 10 alone. 7
- FIG. 6 illustrates a two point fed dipole having segments 50, 51, and52 driven by voltage sources 53, 54 which supply a signal voltage, V.
- voltage sources 53, 54 drive the dipole segments 50, 51, 52 in phase
- the current, I increases from the left extremity, as shown in the drawing, to a, maximum along center segment 51 and then decreases to zero at the right extremity of segment 52.
- This current distribution is similar to that of a typical dipole, with the exception that it is fed at two points instead of one.
- the center segment 51 of FIG. 6 is replaced with the horn 10.
- the current that previously flowed through the center segment 51 divides and flows around opposite sides of the horn 10.
- FIG. 8 shows the dipoles 50, 52 replaced with the choked dipoles 23, 21, respectively, and the voltage sources 53, 54 provided by coaxial lines 33, 31, as in FIG. 1.
- the coaxial lines 31, 33 are, in turn, fed with a 180 four-port hybrid 56.
- the voltages at the outputs of coaxial lines 31, 33 are in anti-phase, creating a null pattern.
- the difference input (A) 58 when fed through the difference input (A) 58, the voltages at the outputs of coaxial lines 31, 33 are in phase, resulting in a good sum pattern.
- the sum and null patterns can be used for monopulse tracking applications.
- the remaining dipoles 20, 22 are fed in phase with a hybrid (not shown) which, in turn, may be fed 90 out of phase relative to the signal applied to hybrid 56, thereby to generate a circularly polarized output signal.
- the feed pattern for each of the three frequency bands be nearly identical in all planes and have a common'center of phase.
- this is achieved by multimoding at 6 GI-Iz so that its effective aperture is less by about three-fourths linear dimension than the physical aperture of the 6/4 GI-Iz horn 10, while at the 4 GHz frequency it is not multimoded so that it has its full physical aperture.
- the horn-dipole assembly is contained in a l GI-Iz cavity formed by ground plane 18, and the metal bands 26, '28 whose parameters are adjusted to shape the 1 GHz patterns without afiecting the 6 and 4 GHz patterns.
- FIGS. 3-5 there is illustrated measured horizontal, vertical, and diagonal patterns for the 4 GI-Iz, 6 GHz, and 1 GHz frequency bands developed by the antenna system of FIGS. 1 and 2, respectively.
- FIG. 3 illustrates a horizontal pattern 60, a vertical pattern 61, and a diagonal pattern 62 for the 4 GHz frequency band
- FIG. 4 illustrates a horizontal pattern 63, a vertical pattern 64, and a diagonal pattern 68 for the 1 GHz frequency band.
- the feed patterns of the antenna system of FIGS. 1 and 2 is nearly identical in all planes for each of the three frequency bands, as is required for antenna feeds of this type.
- the described embodiment of the invention was designed for the 3.7 4.2 GHZ band, the 5.9 6.4 GHz band and the 0.8 1 GHzband, the principles embodied therein are applicable to other frequency bands.
- FIG. 9 shows an aperture view with double choke slots 70, 71' surrounding the periphery of horn 10.
- Choke slot 70 could be designed to impede the 4 GHz frequency band and choke slot 71 designed to impede the 6 CH2 frequency band.
- a circular horn 72 and a crossedhorn 73 are shown, respectively, in place of the square horn 10.
- the choked dipole arms 20-23 emanate from the inside corners thereof.
- FIG. 12 illustrates a horn 74 having indentations adapted to accommodate coaxial lines 30-33.
- a choke slot 75 about the periphery of the horn 74 follows the aforementioned indentations.
- a high efficiency antenna feed system capable of transmitting and receiving simultaneously in first, sec- 0nd, and third increasingly higher frequency bands, said antenna feed system comprising means including a horn for providing a common radiating aperture for signals within said second and third frequency bands;
- first and second arms resonant in conjunction with said horn at said first frequency band and extending outwards from opposite sides of the periphery thereof;
- the high efficiency antenna feed system as defined in claim 1 additionally including means disposed about the periphery of said horn for isolating said first frequency band from said second and third frequency bands.
- said means disposed about the periphery of said horn for isolating said first frequency band from said second and third frequency bands constitutes first and second parallel slots formed of conductive material, said first slot being one quarter wavelength deep at said second frequency band and said second slot being one quarter wavelength deep at said third frequency band, thereby to provide first and second chokes at said second and third frequency bands, respectively.
- the high efficiency antenna feed system as defined in claim 1 additionally including third and fourth arms resonant in conjunction with said horn at said first frequency band and extending outwards from opposite sides of the periphery thereof midway between said first and second arms.
- said means surrounding said horn for providing a cavity for said first frequency band includes means for providing a ground plane outwards from the exterior of the rear portion of said horn normal to the axis of rotation thereof, a plurality of metallic posts disposed intermediate said ground plane and the plane of said first, second, third, and fourth arms at periodic intervals along the circumference of a circle of predetermined radius and having a center coinciding with the axis of rotation of said horn, and first and second parallel metallic bands disposed about said plurality of metallic posts.
- first and second arms extending outwards from opposite sides of the periphery of said horn are connected to first and second arms, respectively, of a four-part hybrid junction, having said first and second arms, a sum arm, and a difference arm.
- a high efficiency antenna feed system capable of transmitting and receiving simultaneously in first, second, and third increasingly higher frequency bands, said antenna feed system comprising a ground plane;
- a horn disposed through said ground plane for providing a common radiating aperture for signals within said second and third frequency bands;
- a step section connected to the input of said horn for multimoding at said third frequency band therein;
- first, second, third, and fourth arms resonant in conjunction with said horn at said first frequency band extending outwards from quadrature points of the periphery thereof;
- first and second parallel metallic bands disposed about said plurality of metallic posts thereby to provide a cavity resonant at said first frequency band
Landscapes
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Computer Networks & Wireless Communication (AREA)
- General Physics & Mathematics (AREA)
- Waveguide Aerials (AREA)
- Aerials With Secondary Devices (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
Priority Applications (8)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US00244158A US3803617A (en) | 1972-04-14 | 1972-04-14 | High efficiency multifrequency feed |
CA167,786A CA977047A (en) | 1972-04-14 | 1973-04-03 | High efficiency multifrequency feed |
DE2316842A DE2316842C3 (de) | 1972-04-14 | 1973-04-04 | Mehrfrequenzantenne für drei Frequenzbänder |
GB1738573A GB1355030A (en) | 1972-04-14 | 1973-04-11 | Antenna feed system |
BR732624A BR7302624D0 (pt) | 1972-04-14 | 1973-04-11 | Alimentacao de alta eficiencia de frequencia multipla |
FR7313570A FR2180114B1 (hu) | 1972-04-14 | 1973-04-13 | |
JP48041489A JPS5224369B2 (hu) | 1972-04-14 | 1973-04-13 | |
IT49428/73A IT988143B (it) | 1972-04-14 | 1973-04-13 | Alimentatore multifrequenza d antenna ad alto rendimento |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US00244158A US3803617A (en) | 1972-04-14 | 1972-04-14 | High efficiency multifrequency feed |
Publications (1)
Publication Number | Publication Date |
---|---|
US3803617A true US3803617A (en) | 1974-04-09 |
Family
ID=22921594
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00244158A Expired - Lifetime US3803617A (en) | 1972-04-14 | 1972-04-14 | High efficiency multifrequency feed |
Country Status (8)
Country | Link |
---|---|
US (1) | US3803617A (hu) |
JP (1) | JPS5224369B2 (hu) |
BR (1) | BR7302624D0 (hu) |
CA (1) | CA977047A (hu) |
DE (1) | DE2316842C3 (hu) |
FR (1) | FR2180114B1 (hu) |
GB (1) | GB1355030A (hu) |
IT (1) | IT988143B (hu) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4028708A (en) * | 1975-10-10 | 1977-06-07 | The United States Of America As Represented By The Secretary Of The Navy | Antenna feed for dual beam conical scan tracking radar |
US4109254A (en) * | 1975-06-17 | 1978-08-22 | The Marconi Company Ltd. | Dipole radiators for feeding a parabolic reflector |
US4207573A (en) * | 1977-05-18 | 1980-06-10 | Thomson-Csf | Dual-frequency antenna system with common reflector illuminated by different feeds |
US4675685A (en) * | 1984-04-17 | 1987-06-23 | Harris Corporation | Low VSWR, flush-mounted, adaptive array antenna |
US4740795A (en) * | 1986-05-28 | 1988-04-26 | Seavey Engineering Associates, Inc. | Dual frequency antenna feeding with coincident phase centers |
US4843399A (en) * | 1986-07-30 | 1989-06-27 | Narco Avionics, Inc. | Portable navigational communications transceiver |
US4862187A (en) * | 1988-10-24 | 1989-08-29 | Microwave Components And Systems, Inc. | Dual band feedhorn with two different dipole sets |
US5003321A (en) * | 1985-09-09 | 1991-03-26 | Sts Enterprises, Inc. | Dual frequency feed |
US5038151A (en) * | 1989-07-31 | 1991-08-06 | Loral Aerospace Corp. | Simultaneous transmit and receive antenna |
US5041840A (en) * | 1987-04-13 | 1991-08-20 | Frank Cipolla | Multiple frequency antenna feed |
US5255003A (en) * | 1987-10-02 | 1993-10-19 | Antenna Downlink, Inc. | Multiple-frequency microwave feed assembly |
US5990838A (en) * | 1996-06-12 | 1999-11-23 | 3Com Corporation | Dual orthogonal monopole antenna system |
US6297782B1 (en) * | 2000-07-26 | 2001-10-02 | Gabriel Electronics Incorporated | Modular hub array antenna |
US6388633B1 (en) * | 1996-11-15 | 2002-05-14 | Yagi Antenna Co., Ltd. | Multibeam antenna |
CN103700924A (zh) * | 2013-12-05 | 2014-04-02 | 清华大学 | 圆极化角度分集天线 |
CN107946746A (zh) * | 2017-10-16 | 2018-04-20 | 西安雷通科技有限责任公司 | Uhf/s双频段卫星通信天线及无线通信系统 |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5816602Y2 (ja) * | 1978-03-16 | 1983-04-04 | シャープ株式会社 | 空気調和装置 |
FR2442519A1 (fr) * | 1978-11-24 | 1980-06-20 | Thomson Csf | Source primaire monopulse imprimee pour antenne de radar aeroporte et antenne comportant une telle source |
DE3544092A1 (de) * | 1985-12-13 | 1987-06-19 | Licentia Gmbh | Mehrbereichsantenne fuer den ghz-bereich |
DE19608622A1 (de) * | 1996-03-06 | 1997-09-11 | Sel Alcatel Ag | Antennenanordnung und Sende- und Empfangsanlage damit |
FR2773271B1 (fr) * | 1997-12-31 | 2000-02-25 | Thomson Multimedia Sa | Emetteur/recepteur d'ondes electromagnetiques |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3205499A (en) * | 1956-08-30 | 1965-09-07 | Avco Mfg Corp | Dual polarized horn antenna |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3325817A (en) * | 1964-06-01 | 1967-06-13 | Hughes Aircraft Co | Dual frequency horn antenna |
-
1972
- 1972-04-14 US US00244158A patent/US3803617A/en not_active Expired - Lifetime
-
1973
- 1973-04-03 CA CA167,786A patent/CA977047A/en not_active Expired
- 1973-04-04 DE DE2316842A patent/DE2316842C3/de not_active Expired
- 1973-04-11 GB GB1738573A patent/GB1355030A/en not_active Expired
- 1973-04-11 BR BR732624A patent/BR7302624D0/pt unknown
- 1973-04-13 JP JP48041489A patent/JPS5224369B2/ja not_active Expired
- 1973-04-13 IT IT49428/73A patent/IT988143B/it active
- 1973-04-13 FR FR7313570A patent/FR2180114B1/fr not_active Expired
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3205499A (en) * | 1956-08-30 | 1965-09-07 | Avco Mfg Corp | Dual polarized horn antenna |
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4109254A (en) * | 1975-06-17 | 1978-08-22 | The Marconi Company Ltd. | Dipole radiators for feeding a parabolic reflector |
US4028708A (en) * | 1975-10-10 | 1977-06-07 | The United States Of America As Represented By The Secretary Of The Navy | Antenna feed for dual beam conical scan tracking radar |
US4207573A (en) * | 1977-05-18 | 1980-06-10 | Thomson-Csf | Dual-frequency antenna system with common reflector illuminated by different feeds |
US4675685A (en) * | 1984-04-17 | 1987-06-23 | Harris Corporation | Low VSWR, flush-mounted, adaptive array antenna |
US5003321A (en) * | 1985-09-09 | 1991-03-26 | Sts Enterprises, Inc. | Dual frequency feed |
US4740795A (en) * | 1986-05-28 | 1988-04-26 | Seavey Engineering Associates, Inc. | Dual frequency antenna feeding with coincident phase centers |
US4843399A (en) * | 1986-07-30 | 1989-06-27 | Narco Avionics, Inc. | Portable navigational communications transceiver |
US5041840A (en) * | 1987-04-13 | 1991-08-20 | Frank Cipolla | Multiple frequency antenna feed |
US5255003A (en) * | 1987-10-02 | 1993-10-19 | Antenna Downlink, Inc. | Multiple-frequency microwave feed assembly |
US4862187A (en) * | 1988-10-24 | 1989-08-29 | Microwave Components And Systems, Inc. | Dual band feedhorn with two different dipole sets |
US5038151A (en) * | 1989-07-31 | 1991-08-06 | Loral Aerospace Corp. | Simultaneous transmit and receive antenna |
US5990838A (en) * | 1996-06-12 | 1999-11-23 | 3Com Corporation | Dual orthogonal monopole antenna system |
US6388633B1 (en) * | 1996-11-15 | 2002-05-14 | Yagi Antenna Co., Ltd. | Multibeam antenna |
US6864850B2 (en) | 1996-11-15 | 2005-03-08 | Yagi Antenna Co., Ltd. | Multibeam antenna |
US6297782B1 (en) * | 2000-07-26 | 2001-10-02 | Gabriel Electronics Incorporated | Modular hub array antenna |
CN103700924A (zh) * | 2013-12-05 | 2014-04-02 | 清华大学 | 圆极化角度分集天线 |
CN107946746A (zh) * | 2017-10-16 | 2018-04-20 | 西安雷通科技有限责任公司 | Uhf/s双频段卫星通信天线及无线通信系统 |
CN107946746B (zh) * | 2017-10-16 | 2019-11-22 | 西安雷通科技有限责任公司 | Uhf/s双频段卫星通信天线及无线通信系统 |
Also Published As
Publication number | Publication date |
---|---|
JPS4921045A (hu) | 1974-02-25 |
IT988143B (it) | 1975-04-10 |
DE2316842A1 (de) | 1973-10-18 |
FR2180114B1 (hu) | 1977-02-04 |
DE2316842B2 (de) | 1978-05-24 |
GB1355030A (en) | 1974-06-05 |
DE2316842C3 (de) | 1979-01-18 |
BR7302624D0 (pt) | 1974-07-11 |
CA977047A (en) | 1975-10-28 |
JPS5224369B2 (hu) | 1977-06-30 |
FR2180114A1 (hu) | 1973-11-23 |
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