Creating a highly sensitive directional antenna with phased arrays or why specialists go abroad
I hasten to dispel possible skepticism about the breeding of "snot" about the weights of innovators in Russia. It will be about the great and advanced technology.
This technology can be applied to various types of antennas over a very wide frequency range from hundreds of megahertz to 10 GHz. The technology is completely new and has no analogues.
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As is known, antennas with phased antenna arrays (HEADLIGHTS) have so far not been widely used in wireless communication systems available in the mass market of telecommunications equipment (in WiMax, LTE, 3G, WiFi, etc.) networks. There were isolated attempts to create such commercial antenna systems, but the results were not suitable for mass use.
And the reason for this is the significant cost of such devices associated with the high price of microwave elements (phase shifters, waveguides, etc.), on which most modern antenna systems with controlled radiation patterns are built and, more importantly, software that is highly non-trivial task within this technology.
Meanwhile, the use of such antennas would lead to a qualitative leap in wireless communications capabilities.
Looking ahead to say that the solution is already there, but first things first.
I will give the main advantages, a schematic description of the technology, options for the possible application of the technology and summarize a brief summary.
Antennas manufactured using this technology have the following advantages:
Our antennas can be made in two versions: with sector scanning and with circular scanning.
Conceptual scheme of a 2.4 GHz high sensitive antenna with high gain and sector scanning capability:
The antenna consists of a mirror (a) formed by a three-dimensional array of controlled diffusers, and a transceiver element (feed) (b).
As controlled diffusers, it is supposed to use electric vibrators loaded at the center by capacitive impedance, the value of which may vary. Variation of the load impedance allows you to adjust the phase of the wave scattered by the vibrator. At the same time, the amplitude of the scattered field also changes. The proposed design (in which the lenses are placed in space, and not on a plane) allows arbitrary changes in the mutual arrangement of the lenses, which expands the possibilities for optimizing its structure to obtain certain characteristics.
Principle of operation:
The principle of operation of the product is as follows - for efficient reception of radiation, the values ​​of the loads of the scatterers should be chosen so that the phases of the waves created by the scatterers ensure the optimal addition of these waves at the point of the transceiver element (feed).
To implement the concept described, the design of the diffuser - the electric dipole, as well as the architecture of the entire mirror formed from diffusers was calculated. In addition, the design of the mirror feed and its location relative to the diffusers was determined.
Diffuser design:
The diffuser is a one-sided printed circuit board and is formed by the shoulders of a dipole (a), an impedance transformer — a long line (b), a varicap (c) connected to a long line, shunt inductors (d) separating the RF portion of the diffuser from the control lines (e), along which a bias voltage is applied to the varicap. A long line (impedance transformer) is introduced into the design to expand the range of load impedance at the dipole input.
Measurements of the test sample showed that the antenna has the following characteristics:
The directivity pattern of the antenna with sector scanning (three patterns correspond to the radiation patterns shifted in the vertical plane):
However, the main link in technology is the software responsible for the formation of the required radiation pattern. A control system using the mechanisms of self-organization (self-tuning) of the array of diffusers was chosen.
Circular scanning antennas built using the UPR technology are formed by a multi-tiered collinear antenna surrounded by a layer of passive diffusers of a special design (calculated taking into account the influence of closely located active element and control lines on their characteristics).
For the second type of antennas, the following characteristics are achieved:
Circular scanning antenna pattern:
It is worth noting that the technology has been thoroughly developed, has been tested in real conditions and has shown excellent results.
Also, there is no doubt that the prospects for this technology are extremely high, if not to say that it has a future.
For a more detailed description can be found with the presentation .
Thanks for attention. I will be glad to any questions, comments. And investment proposals.
Highly sensitive antennas based on an array of controlled passive diffusers
This technology can be applied to various types of antennas over a very wide frequency range from hundreds of megahertz to 10 GHz. The technology is completely new and has no analogues.
')
As is known, antennas with phased antenna arrays (HEADLIGHTS) have so far not been widely used in wireless communication systems available in the mass market of telecommunications equipment (in WiMax, LTE, 3G, WiFi, etc.) networks. There were isolated attempts to create such commercial antenna systems, but the results were not suitable for mass use.
And the reason for this is the significant cost of such devices associated with the high price of microwave elements (phase shifters, waveguides, etc.), on which most modern antenna systems with controlled radiation patterns are built and, more importantly, software that is highly non-trivial task within this technology.
Meanwhile, the use of such antennas would lead to a qualitative leap in wireless communications capabilities.
Looking ahead to say that the solution is already there, but first things first.
I will give the main advantages, a schematic description of the technology, options for the possible application of the technology and summarize a brief summary.
Benefits
Antennas manufactured using this technology have the following advantages:
- Low cost - up to $ 500 for base stations and up to $ 100 for client stations;
- Automatic generation of distributed wireless networks with multiple nodes;
- Minimizing the impact of interference sources on the quality of communication;
- Minimizing the negative impact on the communication quality of signal reflections from surrounding objects;
- Determining the direction to a moving signal source;
- Low power consumption;
- High speed switching of end states;
- Fast communication interface with computing device;
- High accuracy of the output signal (voltage);
- Ability to reconfigure.
Technology description
Our antennas can be made in two versions: with sector scanning and with circular scanning.
Circular scan antennas.
Conceptual scheme of a 2.4 GHz high sensitive antenna with high gain and sector scanning capability:
The antenna consists of a mirror (a) formed by a three-dimensional array of controlled diffusers, and a transceiver element (feed) (b).
As controlled diffusers, it is supposed to use electric vibrators loaded at the center by capacitive impedance, the value of which may vary. Variation of the load impedance allows you to adjust the phase of the wave scattered by the vibrator. At the same time, the amplitude of the scattered field also changes. The proposed design (in which the lenses are placed in space, and not on a plane) allows arbitrary changes in the mutual arrangement of the lenses, which expands the possibilities for optimizing its structure to obtain certain characteristics.
Principle of operation:
The principle of operation of the product is as follows - for efficient reception of radiation, the values ​​of the loads of the scatterers should be chosen so that the phases of the waves created by the scatterers ensure the optimal addition of these waves at the point of the transceiver element (feed).
To implement the concept described, the design of the diffuser - the electric dipole, as well as the architecture of the entire mirror formed from diffusers was calculated. In addition, the design of the mirror feed and its location relative to the diffusers was determined.
Diffuser design:
The diffuser is a one-sided printed circuit board and is formed by the shoulders of a dipole (a), an impedance transformer — a long line (b), a varicap (c) connected to a long line, shunt inductors (d) separating the RF portion of the diffuser from the control lines (e), along which a bias voltage is applied to the varicap. A long line (impedance transformer) is introduced into the design to expand the range of load impedance at the dipole input.
Measurements of the test sample showed that the antenna has the following characteristics:
- The operating frequency range is 2.4 GHz;
- Width of the working frequency band up to 200 MHz;
- The gain of the antenna array is more than 21dBi with the dimensions of the antenna array 60 cm x 100 cm;
- Rearrangement of the main lobe of the radiation pattern from -60 to + 60 in the azimuthal plane and from -15o to + 15o in elevation;
- Ensuring the stability of reception / transmission when the environment changes, as well as support for multi-user modes of operation while meeting the requirements of high speed switching of final states and interface speed.
- The average data transfer rate for WiFi devices (IEEE 802.11b) is 6.85 Mbps at a distance of 6.5 km
- Number of simultaneous connections - 135
The directivity pattern of the antenna with sector scanning (three patterns correspond to the radiation patterns shifted in the vertical plane):
However, the main link in technology is the software responsible for the formation of the required radiation pattern. A control system using the mechanisms of self-organization (self-tuning) of the array of diffusers was chosen.
Circular scan version
Circular scanning antennas built using the UPR technology are formed by a multi-tiered collinear antenna surrounded by a layer of passive diffusers of a special design (calculated taking into account the influence of closely located active element and control lines on their characteristics).
For the second type of antennas, the following characteristics are achieved:
- working frequency range - 2.4 GHz
- bandwidth is 100/200 MHz
- Gain - up to 8 dBi
- scan angle range - 360 degrees in the horizontal plane
Circular scanning antenna pattern:
Possible options for the commercialization of technology
- Creation of a 3G / LTE modem equipped with a controlled antenna;
- Creating a WiFi access point equipped with a controlled antenna;
- Creation of self-tuned antennas for rapidly deployable communication systems in unprepared areas (including those with a large number of nodes);
- Creating RFID long range systems;
- Creation of client terminals for satellite communication systems;
- Creation of security radar systems;
- Creation of systems of direction finding of mobile objects moving in a limited area;
- Creation of distributed antenna systems (DAS technology).
Afterword
It is worth noting that the technology has been thoroughly developed, has been tested in real conditions and has shown excellent results.
Also, there is no doubt that the prospects for this technology are extremely high, if not to say that it has a future.
For a more detailed description can be found with the presentation .
Thanks for attention. I will be glad to any questions, comments. And investment proposals.
Source: https://habr.com/ru/post/133787/
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