CN113473586A - Wireless video transmission system power control method for high-definition video transmission - Google Patents
Wireless video transmission system power control method for high-definition video transmission Download PDFInfo
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- CN113473586A CN113473586A CN202010233964.6A CN202010233964A CN113473586A CN 113473586 A CN113473586 A CN 113473586A CN 202010233964 A CN202010233964 A CN 202010233964A CN 113473586 A CN113473586 A CN 113473586A
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- 230000005540 biological transmission Effects 0.000 title claims abstract description 128
- 238000000034 method Methods 0.000 title claims abstract description 49
- 230000007246 mechanism Effects 0.000 claims description 6
- 230000005236 sound signal Effects 0.000 claims description 6
- 230000003321 amplification Effects 0.000 claims description 3
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 3
- 230000008569 process Effects 0.000 description 5
- 230000008054 signal transmission Effects 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000010295 mobile communication Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/06—TPC algorithms
- H04W52/14—Separate analysis of uplink or downlink
- H04W52/146—Uplink power control
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N7/00—Television systems
- H04N7/18—Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/18—TPC being performed according to specific parameters
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/18—TPC being performed according to specific parameters
- H04W52/24—TPC being performed according to specific parameters using SIR [Signal to Interference Ratio] or other wireless path parameters
- H04W52/241—TPC being performed according to specific parameters using SIR [Signal to Interference Ratio] or other wireless path parameters taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/54—Signalisation aspects of the TPC commands, e.g. frame structure
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- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Computer Networks & Wireless Communication (AREA)
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Abstract
The invention discloses a power control method of a wireless video transmission system aiming at high-definition video transmission, and relates to the technical field of power control of the wireless video transmission system. The system consists of a wireless video transmission base station, a video transmitting terminal and a video-audio decoder, and is matched with a monitor and a camera for use, and the wireless video transmission base station receives the signal power and the bit error rate transmitted by the video transmitting terminal for comprehensive calculation. The invention relates to a power control method of a wireless video transmission system aiming at high-definition video transmission, which adopts a wireless video transmission base station to receive signal power and error rate transmitted by a video transmitting terminal to carry out comprehensive calculation, thereby obtaining the power control method of the wireless video transmission base station system aiming at high-definition video transmission, not only realizing automatic adjustment of power, but also ensuring stable transmission rate of high-definition video signals, and having better market popularization value.
Description
Technical Field
The invention relates to the technical field of power control of wireless video transmission systems, in particular to a power control method of a wireless video transmission system for high-definition video transmission.
Background
The wireless video transmission system is a monitoring system which transmits signals such as video, sound and data by using radio waves without wiring, and wireless image transmission, namely video real-time transmission, mainly has two concepts, namely mobile transmission, namely mobile communication, broadband transmission, namely broadband communication, and the common wireless video transmission modes are four: the wireless image transmission system mainly has two concepts, namely mobile transmission, namely mobile communication, and wide/narrow band transmission, namely wide/narrow band communication, so that the wireless image transmission system capable of stably transmitting high-definition videos with very wide frequency bands in a high-speed moving process is developed.
Currently, the requirement of broadcast television on the stability of high definition video signal transmission is very high when the program is broadcast directly, and the stability of signal transmission bandwidth must be ensured to maintain the stability of video signal transmission.
The method is to adopt the target power of all terminals reaching the base station to keep constant, so as to meet the requirement, the power transmitted by the terminals in the moving process is inevitably changed rapidly, the rapidly changed power inevitably causes instability of transmission rate, and the application requirement of high-definition video transmission cannot be met only by using the power adjusting method, so that the power control method of the wireless video transmission base station, which can realize automatic adjustment of the power and can ensure the stability of the transmission rate of high-definition video signals, is urgently needed.
Disclosure of Invention
The invention provides a power control method of a wireless video transmission system aiming at high-definition video transmission, which has the advantages of realizing automatic adjustment of power and ensuring stable transmission rate of high-definition video signals, and solves the problem of unstable transmission rate of the traditional wireless video transmission base station system.
In order to realize the purpose of realizing the power control method of the wireless video transmission base station, which can realize the automatic adjustment of the power and ensure the stable transmission rate of the high-definition video signal, the invention provides the following technical scheme: the video and audio monitoring system is characterized by comprising a camera, a video transmitting terminal, a wireless video transmission base station, a video and audio decoder and a monitor, wherein the output end of the camera is electrically connected with the input end of the video transmitting terminal, the two-way electrical connection of the output end of the video transmitting terminal is connected with the input end of the wireless video transmission base station, the output end of the wireless video transmission base station is electrically connected with the input end of the video and audio decoder, and the output end of the video and audio decoder is electrically connected with the input end of the monitor.
A power control method of a wireless video transmission system aiming at high-definition video transmission comprises the following steps:
s1: SDI video and audio signals of the camera are sent to a video transmitting terminal for video and audio coding, then IP data streams are subjected to signal coding and debugging, and then signal amplification is carried out through a power amplifier, and the signals are sent to a wireless video transmission base station through a transmitting antenna;
s2: the wireless video transmission base station receives the wireless video signals of the video transmitting terminal and restores the wireless video signals into IP data streams, and meanwhile, the management and coordination of the video transmitting terminal are realized;
s3: the IP data stream is restored into SDI video and audio signals through a video and audio decoder and then is sent to a monitor for picture display and sound playing.
As a preferred technical scheme of the invention, the wireless video transmission base station receives the Receive level and BER transmitted by the video transmitting terminal and carries out comprehensive calculation so as to obtain the power control method of the wireless video transmission base station system for high-definition video transmission.
As a preferred technical scheme of the invention, when the wireless video transmission base station receives that the error rate sent to the base station by all video transmitting terminals is within a normal allowable range, the wireless video transmission base station keeps an original power control mechanism.
As a preferred technical scheme of the invention, all target power from all video transmitting terminals to the base station is controlled to be kept constant by the wireless video transmission base station.
As a preferred technical scheme of the invention, when a wireless video transmission base station receives that the error rate sent to the base station by a certain video transmitting terminal exceeds the allowable range, the wireless video transmission base station sends a power control instruction to gradually adjust the transmitting power of the radio frequency transmitting terminal to enable the transmitting power to reach the maximum transmitting power, and other video transmitting terminals keep the original power control mechanism.
As a preferred embodiment of the present invention, the Receive level refers to a signal power, and the BER refers to a bit error rate.
Compared with the prior art, the invention provides a power control method of a wireless video transmission system aiming at high-definition video transmission, which has the following beneficial effects:
the invention relates to a power control method of a wireless video transmission system aiming at high-definition video transmission, which adopts a wireless video transmission base station to receive signal power and error rate transmitted by a video transmitting terminal to carry out comprehensive calculation, thereby obtaining the power control method of the wireless video transmission base station system aiming at high-definition video transmission, not only realizing automatic adjustment of power, but also ensuring stable transmission rate of high-definition video signals, and having better market popularization value.
Drawings
Fig. 1 is a diagram of a wireless video transmission system for a wireless video transmission system power control method for high definition video transmission according to the present invention;
fig. 2 is a power control method diagram of a power control method of a wireless video transmission system for high definition video transmission according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Please refer to fig. 1, which comprises a camera, a video transmitting terminal, a wireless video transmission base station, a video/audio decoder and a monitor, wherein an output terminal of the camera is electrically connected to an input terminal of the video transmitting terminal, an output terminal of the video transmitting terminal is bidirectionally electrically connected to an input terminal of the wireless video transmission base station, an output terminal of the wireless video transmission base station is electrically connected to an input terminal of the video/audio decoder, an output terminal of the video/audio decoder is electrically connected to an input terminal of the monitor, and the wireless video transmission base station is adopted to receive signal power and error rate transmitted by the video transmitting terminal for comprehensive calculation, so as to obtain a power control method of the wireless video transmission base station system for high-definition video transmission, which can realize automatic adjustment of power and ensure stable transmission rate of high-definition video signals, has better market popularization value.
A power control method of a wireless video transmission system aiming at high-definition video transmission comprises the following steps:
s1: SDI video and audio signals of the camera are sent to a video transmitting terminal for video and audio coding, then IP data streams are subjected to signal coding and debugging, and then signal amplification is carried out through a power amplifier, and the signals are sent to a wireless video transmission base station through a transmitting antenna;
s2: the wireless video transmission base station receives the wireless video signals of the video transmitting terminal and restores the wireless video signals into IP data streams, and meanwhile, the management and coordination of the video transmitting terminal are realized;
s3: the IP data stream is restored into SDI video and audio signals through a video and audio decoder and then is sent to a monitor for picture display and sound playing.
Referring to fig. 2, the specific method for controlling the power of the wireless video transmission system for high definition video transmission according to the present invention includes: the power control method of the wireless video transmission base station system for high-definition video transmission is obtained by comprehensively calculating the power (Receive level) and the Bit Error Rate (BER) of signals transmitted by video transmitting terminals received by the wireless video transmission base station, and the principle is that when the bit error rate of all the video transmitting terminals transmitted to the base station received by the wireless video transmission base station is within a normal allowable range, the wireless video transmission base station keeps an original power control mechanism, namely all target powers of all the video transmitting terminals to the base station are controlled to be kept constant by the wireless video transmission base station; when the wireless video transmission base station receives that the error rate sent to the base station by a certain video transmitting terminal exceeds the allowable range, the wireless video transmission base station sends a power control instruction, the transmitting power of the radio frequency transmitting terminal is gradually adjusted to reach the maximum transmitting power, and other video transmitting terminals keep the original power control mechanism.
The specific embodiment is as follows: assuming that the target power of the video transmitting terminal received by the wireless video transmission base station is Pi, the method for calculating the transmitting Po of the video transmitting terminal is as follows:
Po=Pi-Go-Gi+Ls
wherein: po is the transmission power (dBm) of the video transmitting terminal,
gt is the gain (dB) of the transmitting antenna of the video transmitting terminal,
gr is the gain (dB) of the receiving antenna of the wireless video transmission base station,
ls is the free space loss (dB),
ls =92.4+20logd +20logf (d is the distance between the base station and the terminal in km, f is the operating frequency in GHz).
Assuming that the transmission power of all video transmitting terminals accessing the wireless video transmission base station is P1 and P2. Setting the bit error rate of signals sent by the video transmitting terminal and received by the wireless video transmission base station as BER, and when the value of BER is less than n (the value of n can be set by software according to actual use conditions), the wireless video transmission base station transmits a power control instruction to each video transmitting terminal according to the power adjustment method; when the BER value uploaded to the wireless video transmission base station by one or more video transmitting terminals is larger than or equal to n, the wireless video transmission base station issues a power control command to adjust the transmitting power of the terminals to the maximum Pmax, and other terminals with BER in a normal range keep unchanged. The wireless video transmission base station reduces the rapid change of the power of the terminal under the condition of poor wireless environment through the power control mode, and simultaneously, the power of the terminal can be transmitted to the maximum according to the BER condition, thereby ensuring the stability of video stream transmission.
The above description is only a preferred embodiment of the present invention, and all equivalent changes and modifications made in accordance with the claims of the present invention should be covered by the present invention.
In summary, the power control method of the wireless video transmission system for high-definition video transmission adopts the wireless video transmission base station to receive the signal power and the error rate transmitted by the video transmitting terminal for comprehensive calculation, so as to obtain the power control method of the wireless video transmission base station system for high-definition video transmission, which can realize automatic adjustment of power and ensure stable transmission rate of high-definition video signals, and has good market popularization value.
The power control method of the wireless video transmission system for high-definition video transmission has the advantages of realizing automatic power adjustment and ensuring stable transmission rate of high-definition video signals, and solves the problem of unstable transmission rate of the traditional wireless video transmission base station system.
It should be noted that, in this document, terms such as "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (7)
1. The utility model provides a wireless video transmission system to high definition video transmission, includes that camera, video transmission terminal, wireless video transmission basic station, audio decoder and monitor constitute which characterized in that: the output end of the camera is electrically connected with the input end of a video transmitting terminal, the output end of the video transmitting terminal is bidirectionally electrically connected with the input end of a wireless video transmission base station, the output end of the wireless video transmission base station is electrically connected with the input end of a video and audio decoder, and the output end of the video and audio decoder is electrically connected with the input end of a monitor.
2. A power control method of a wireless video transmission system aiming at high-definition video transmission is characterized in that: the method comprises the following steps:
s1: SDI video and audio signals of the camera are sent to a video transmitting terminal for video and audio coding, then IP data streams are subjected to signal coding and debugging, and then signal amplification is carried out through a power amplifier, and the signals are sent to a wireless video transmission base station through a transmitting antenna;
s2: the wireless video transmission base station receives the wireless video signals of the video transmitting terminal and restores the wireless video signals into IP data streams, and meanwhile, the management and coordination of the video transmitting terminal are realized;
s3: the IP data stream is restored into SDI video and audio signals through a video and audio decoder and then is sent to a monitor for picture display and sound playing.
3. The method of claim 2, wherein the method comprises the steps of: the wireless video transmission base station receives the Receive level and the BER transmitted by the video transmitting terminal to carry out comprehensive calculation, thereby obtaining the power control method of the wireless video transmission base station system aiming at high-definition video transmission.
4. The method of claim 2, wherein the method comprises the steps of: when the wireless video transmission base station receives that the error rate sent to the base station by all the video transmitting terminals is within the normal allowable range, the wireless video transmission base station keeps the original power control mechanism.
5. The method of claim 4, wherein the method comprises the following steps: and controlling all the video transmitting terminals to keep all the target power from the base station to be constant through the wireless video transmission base station.
6. The method of claim 2, wherein the method comprises the steps of: when the wireless video transmission base station receives that the error rate sent to the base station by a certain video transmitting terminal exceeds the allowable range, the wireless video transmission base station sends a power control instruction, the transmitting power of the radio frequency transmitting terminal is gradually adjusted to reach the maximum transmitting power, and other video transmitting terminals keep the original power control mechanism.
7. The method of claim 3, wherein the method comprises the following steps: the Receive level refers to signal power, and the BER refers to bit error rate.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010233964.6A CN113473586A (en) | 2020-03-30 | 2020-03-30 | Wireless video transmission system power control method for high-definition video transmission |
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| CN202010233964.6A CN113473586A (en) | 2020-03-30 | 2020-03-30 | Wireless video transmission system power control method for high-definition video transmission |
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