Conversion of wireless power mW and DBM and interpretation of common symbols
1. Conversion of power unit mW and DBM The RF signal output by the radio transmitter is transmitted to the antenna through a feeder (Cable), which emits electromagnetic waves. After the electromagnetic wave arrives at the receiving location, it is received by the antenna (only a small portion of the power is r
the RF signal of the radio transmitters output is transmitted to the antenna via a feeder (cable) and radiated out by the antenna in the form of electromagnetic waves. When the electromagnetic wave arrives at the receiving location, it is received by the antenna (only a small fraction of the power is received) and sent to the radio receiver via the feeder. Therefore, it is very important to calculate the transmitting power of the transmitting device and the radiation ability of the antenna in
The RF signal of the radio transmitters output is transmitted to the antenna via a feeder (cable) and radiated out by the antenna in the form of electromagnetic waves. ElectromagneticWhen the wave arrives at the receiving location, it is received by the antenna (only a small fraction of the power is received) and sent to the radio receiver via the feeder.Therefore, it is very important to calculate the transmitting power of the transmitting device and the radiation ability of the antenna in the
Modified: MW [memory address] [value] [length]Example: MW 0x02000000 0 128Represents a memory value of 0 that modifies the address to 0x02000000~0x02000000+128.Display: MD [memory address] [length]Example: MD 0x02000000 128Represents the memory data for the display of 0x02000000, with a length of 128 32bit.Note the value of [length], for example:# MD 02000000 1002000000:FFFFFFFF ffffffff ffffffff ffffffff .
through the circle is forcibly calculated by x-coordinate : (x-a) ^2+ ( Y-b) ^2=r^2 (A, A, a, b) for the center of R is the radius x, Y is a point on the arc y-b = math.sqrt (R^2-(x-a) ^2) = y = math.sqrt (r^2-(x-a) ^2) + B
or -(y-b) = Math.sqrt (R^2-(x-a) ^2) + y =-1 * MATH.SQRT (r^2-(x-a) ^2) + b */// mtouchy = (float) ( Math.sqrt ((Math.pow (MW, 2)-Math.pow (Mtouchx, 2)) + MH); The apparent value is greater than MH, not
, the address is sent first, and then data is obtained, which is the same as the normal READ memory.
Reset Mode, Write to any address0xF0All exit special mode
Read IDNor flash is divided into 1-byte and 2-byte modes, so there are two types of operation commands. The onboard is 2 bytes. The operation is as follows:
Sending address 555, sending data AA, 0x555*2 = 0 xaaa
Sending address 2AA, sending data 55 0x2aa * 2 = 0x554
Sending address 555, sending data 90 0x555*2 = 0 xaaa
Sen
DBMPower Unit and P (Watt) conversion formula:DBM = 30 + 10lgp (P: Tile)First, DB is a pure counting unit: DB = 10 logX. The significance of DB is actually a simple one, that isThe number of large (followed by a long string of 0) or small (followed by a long string of 0) is briefly expressed. For example:X = 1000000000000000 (How many ?) = 10 logX = 150 dBX = 0.000000000000001 = 10 logX =-150 dBDBM defines miliwatt. 0 dBm = 10log1 MW;Dbw defines Watt.
is to traverse all, some words will not be generated, no words to generate a, and the first is a parameter, and finally the window event.changedistingwordofselected MW = NULL;foreach (Window winIn APP. Current. Windows){If (Win is changedistingwordofselected){MW = win as changedistingwordofselected;}}if (MW = = null){MW
MediaWiki installation under WindowsFor friends who have just contacted the wiki, configuring a server environment, installing and running MediaWiki is a very troublesome thing, here, I try to use the easy-to-understand language, the installation process of MW (MediaWiki, hereinafter) under Windows.MW is developed using PHP, PHP is a recently mature web scripting language, in order to run a PHP-based program, you need to configure PHP operating enviro
is actually a RF noise source, which causes signals in the room to be squashed. However, the current wireless technology can ensure that the receiving device works normally under a low signal-to-noise ratio.
The transmit power of RF signals is often measured in watt. The output power of a surround sound system is usually about 500 watts, while that of a microwave-based RF system is much lower. Even if the maximum power of the Wi-Fi system, the transmit power is only 200
Copy Code code as follows:
Mainly used to collect IP, Mac, name, room, and then added the maintenance record function. The server side accepts the data and stores it in the database.
#############################
Use strict;
Use Tk;
Use Encode;
#SOCKE参数
My $PF _inet = 2;
my $port = 2345;
My $remote _addr = Pack (' snc4x8 ', $PF _inet, $port, 192,168,138,228);
My $SOCK _dgram = 2;
#Frame
My ($label _room, $label _name, $label _ctrl, $label _notice);
#确定, cancellation
My ($
. That is to say, after a table is connected, something similar to a temporary view is generated. Where filters data from this temporary view, first, you need to find out which of your so-called two conditions belong. Delete Delete Statement is similar Delete From T1 From T1 Inner Join T2 On T1.id = T2.tid pay attention to the blue part. MySQL: SQL code Delete Mwb From Mem_world_building As Mwb Inner Join Mem_world As MW On Mwb. wid =
voltage amplitude is only 0.707 (1/) times the median frequency segment. For example-3 db, if the pass-band frequency magnification is 1, that is, the Aup is 1, that is, the filter circuit in the pass band without amplification voltage, then -3=20log (AU/AUP) =20log (Au), calculated au=0.707, in this case, -3 db signal attenuation is the original 7 0.7%. 0 DB indicates that the output is as large as the input or two comparison signals. The decibel is a relative size, with no absolute measure. Y
1. DBDB is a value that represents relative values. A pure ratio represents only the relative size relationship between two quantities, with no unit, when considering the number of DB whose power is larger or smaller than that of B,
The formula below is as follows: 10log (a power/B power). If the ratio of the two is used, 20log (a voltage/B voltage) is used ).)[Example] If the power of a is twice the power of B, then 10lg (the power of a/B) = 10lg2 = dB. That is to say, the power of a is 3 dB
electromagnetic radiation will affect and damage the original biological current and biological magnetic field of the human body, causes an exception to the original electromagnetic field in the human body. It is worth noting that different people or the same person have different capacities for electromagnetic radiation in different age groups. The elderly, children, and pregnant women are sensitive to electromagnetic radiation, weak resistance should be our key protection targets. It is best
electric waves all the time. High-dose electromagnetic radiation will affect and damage the original biological current and biological magnetic field of the human body, causes an exception to the original electromagnetic field in the human body. It is worth noting that different people or the same person have different capacities for electromagnetic radiation in different age groups. The elderly, children, and pregnant women are sensitive to electromagnetic radiation, weak resistance should be
DD-WRT equipment can help us to achieve any adjustment of the purpose of the transmit power, so that we can be based on the wireless network card distance from the DD-WRT wireless router to determine the strength of the transmit signal. Below we speak with the facts, step by step teach readers how to adjust the transmit signal power in the DD-WRT equipment, and compare the received effect before and after the adjustment.
I. Default reception results:
We turn on the DD-WRT wireless device, wi
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