CN1996661A - The method for making the vehicular antennal with the leaky coaxial cable - Google Patents

Abstract

The invention relates to a method for making a vehicle-mounted antenna by using a leaky coaxial cable, which utilizes a long longitudinal slot to leak a coaxial nλ/4 short-circuit line as the transmitting and receiving antenna of the vehicle-mounted system. Where n is an odd number of 1, 3, 5, 7, 9, 11, 13, 15..., and λ is the electromagnetic wave wavelength of the vehicle-mounted transmitting antenna or receiving antenna, respectively. The coupling performance between the antenna and the leaky coaxial is stable and reliable, so that the vehicle-mounted antenna receiving system has a high degree of defense against external electromagnetic wave interference, and the field strength of the vehicle-mounted transmitting antenna system decays rapidly with the increase of distance, which has great social benefits and economic benefits.

Description

The Method of Using Leaky Coaxial Cable to Make Vehicle-mounted Antenna

technical field

The invention relates to the technical field of rail transit vehicle-ground communication. Specifically, it is a method of using leaky coaxial cables to make vehicle-mounted antennas, which is applied in high-speed railway vehicle-to-ground communication.

Background technique

At present, the vehicle-mounted antennas in leaky coaxial vehicle-to-ground communication generally use "dipole" antennas, surface wave antennas or other antennas with strong directivity, but these antennas are open antennas, and the vehicle-mounted transmission system will Electromagnetic field interference is generated, and the vehicle receiving system is also susceptible to interference from external electromagnetic waves. The vehicle-ground communication system is related to the safety of driving. If it is interfered by external sources, it will increase error codes and even cause errors in driving instructions. Especially in extraordinary times, it is easy for the enemy to use many radio stations in remote areas to attack the vehicle-ground communication system of the traffic command, resulting in the paralysis of the vehicle-ground traffic system. There is an urgent need to develop a new type of vehicle-mounted antenna with high directivity and rapid attenuation of field strength with increasing distance.

Contents of the invention

The object of the present invention is to provide a method for making a vehicle-mounted antenna by using a leaky coaxial cable, which can be used to make a new type of vehicle-mounted antenna with extremely high directivity and rapid attenuation characteristics of field strength with increasing distance.

The present invention is achieved like this:

1. Copper strips are longitudinally wrapped on the leaky coaxial physical foaming insulating medium to form the leaky coaxial outer conductor, and then directly enter the sheath extruder to extrude the sheath.

2. Intercept a leaky coaxial section with a length of nλ/4, where n is an odd number of 1, 3, 5, 7, 9, 11, 13, 15..., and λ is the electromagnetic wave wavelength of the vehicle-mounted transmitting antenna or receiving antenna. Then the intercepted leaky coaxial terminal inner conductor and outer conductor are sealed and short-circuited with a copper sheet with the same diameter as the outer conductor, and the inner and outer conductors at the beginning end are respectively connected to the inner and outer conductors of the feeder line to form a longitudinal long slot leaky coaxial vehicle antenna.

The coupling performance between the antenna and the leaky coaxial is stable and reliable, so that the vehicle-mounted antenna receiving system has a high degree of defense against external electromagnetic wave interference, and the field strength of the vehicle-mounted transmitting antenna system decays rapidly with the increase of distance, which has great social benefits and economic benefits.

Description of drawings

Accompanying drawing 1 is the structure schematic diagram of coaxial vehicle-mounted antenna with longitudinal slot leakage.

Detailed ways

1. Copper tape is longitudinally wrapped on the leaky coaxial physical foamed polyethylene insulating medium (2), and the width of the copper tape is about 2/3 of the diameter of the outer layer of the physical foamed polyethylene insulating layer, forming a leaky coaxial The outer conductor (3) then directly enters the sheath extruder to extrude a polyethylene sheath (4) with a thickness of 2.5 mm.

2. Intercept the leaky coaxial with a length of nλ/4, where n is an odd number of 1, 3, 5, 7, 9, 11, 13, 15..., and λ is the electromagnetic wave wavelength of the vehicle-mounted transmitting antenna or receiving antenna. Seal and short-circuit the intercepted leakage coaxial terminal inner conductor (1) and outer conductor (3) with a copper sheet (5) whose diameter is the same as that of the outer conductor. Leaky coaxial vehicle antenna (6).

Claims (1)

1. a method of utilizing leaky coaxial cable to make car antenna is characterized in that

1) goes up vertical copper-clad band at the physical foam insulation medium (2) of leakage coaxial, constitute the outer conductor (3) of leakage coaxial, directly enter sheath plastic extruding machine extrusion molding sheath (4) then;

2) intercepting one segment length is the leakage coaxial of n λ/4, and wherein n is 1,3,5,7,9,11,13,15 ... odd number, λ is respectively the electromagnetic wavelength of vehicle-mounted transmitting antenna or reception antenna; And then the terminal inner wire (1) of leakage coaxial and the outer conductor (3) of intercepting sealed short circuit with the diameter copper sheet (5) consistent with the outer conductor diameter, the top internal and external conductor connects the internal and external conductor of feeder line respectively, promptly makes vertical elongated slot leakage coaxial car antenna (6).