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25-1218: (Redirected from TISEO ) [REDACTED] The Target Identification System Electro-Optical ( TISEO ) is the Target identification device used in the F-4 Phantom and F-14 Tomcat that provides sharp close-up images of hostile aircraft outside of visual range. See also [ edit ] List of military electronics of the United States References [ edit ] ^ https://www.ausairpower.net/TE-EO-Systems.html External links [ edit ] F-14 Tomcat Military Analysis Network , Federation of American Scientists Camera Set, Television, An / Axx -1 , Integrated Publishing AN/AXX-1 TV control system , iNews CMANO-DB - AN/ASX-1 TISEO Designation-Systems.net - AN/ASR to AN/ASX - Equipment Listing Retrieved from " https://en.wikipedia.org/w/index.php?title=Target_Identification_System_Electro-Optical&oldid=1244929065 " Category : Targeting pods Target identification Target recognition

50-448: A low-pass filter . By contrast, passband bandwidth is the difference between a highest frequency and a nonzero lowest frequency. A baseband channel or lowpass channel (or system , or network ) is a communication channel that can transfer frequencies that are very near zero. Examples are serial cables and local area networks (LANs), as opposed to passband channels such as radio frequency channels and passband filtered wires of

75-501: A bandpass filtered channel, such as the telephone network local-loop or a band-limited wireless channel. The word "BASE" in Ethernet physical layer standards, for example 10BASE5 , 100BASE-TX and 1000BASE-SX , implies baseband digital transmission (i.e. that a line code and an unfiltered wire are used). A baseband processor also known as BP or BBP is used to process the down-converted digital signal to retrieve essential data for

100-494: A battlefield to filtering out interference caused by large flocks of birds on Doppler weather radar. Possible military applications include a simple identification system such as an IFF transponder , and is used in other applications such as unmanned aerial vehicles and cruise missiles . There has been more and more interest shown in using ATR for domestic applications as well. Research has been done into using ATR for border security, safety systems to identify objects or people on

125-473: A certain pattern, or signature, that will allow for algorithms to be developed for ATR. The micro-Doppler effect will change over time depending on the motion of the target, causing a time and frequency varying signal. Fourier transform analysis of this signal is not sufficient since the Fourier transform cannot account for the time varying component. The simplest method to obtain a function of frequency and time

150-398: A concept within analog and digital modulation methods for (passband) signals with constant or varying carrier frequency (for example ASK , PSK QAM , and FSK ). The equivalent baseband signal is Z ( t ) = I ( t ) + j Q ( t ) {\displaystyle Z(t)=I(t)+jQ(t)\,} where I ( t ) {\displaystyle I(t)}

175-423: A high probability of success. CNN-Based Target Recognition Convolutional neural network (CNN)-based target recognition is able to outperform the conventional methods. It has been proved useful in recognizing targets (i.e. battle tanks) in infrared images of real scenes after training with synthetic images, since real images of those targets are scarce. Due to the limitation of the training set, how realistic

200-547: A model is obtained using the data collected, conditional probability is formed for each target contained in the training database. In this example, there are M blocks of data. This will result in a collection of M probabilities for each target in the database. These probabilities are used to determine what the target is using a maximum likelihood decision. This method has been shown to be able to distinguish between vehicle types (wheeled vs tracked vehicles for example), and even decide how many people are present up to three people with

225-520: A subway track, automated vehicles, and many others. Target recognition has existed almost as long as radar . Radar operators would identify enemy bombers and fighters through the audio representation that was received by the reflected signal (see Radar in World War II ). Target recognition was done for years by playing the baseband signal to the operator. Listening to this signal, trained radar operators can identify various pieces of information about

250-449: A training database needs to be created. This is usually done using experimental data collected when the target is known, and is then stored for use by the ATR algorithm. An example of a detection algorithm is shown in the flowchart. This method uses M blocks of data, extracts the desired features from each (i.e. LPC coefficients, MFCC) then models them using a Gaussian mixture model (GMM). After

275-446: A wireless digital system. The baseband processing block in GNSS receivers is responsible for providing observable data: that is, code pseudo-ranges and carrier phase measurements, as well as navigation data. An equivalent baseband signal or equivalent lowpass signal is a complex valued representation of the modulated physical signal (the so-called passband signal or RF signal). It is

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300-409: Is a signal that can include frequencies that are very near zero, by comparison with its highest frequency (for example, a sound waveform can be considered as a baseband signal, whereas a radio signal or any other modulated signal is not). A baseband bandwidth is equal to the highest frequency of a signal or system, or an upper bound on such frequencies, for example the upper cut-off frequency of

325-518: Is not stationary, it causes a frequency shift known as the Doppler effect . In addition to the translational motion of the entire object, an additional frequency shift can be caused by the object vibrating or spinning. When this happens the Doppler shifted signal will become modulated. This additional Doppler effect causing the modulation of the signal is known as the micro-Doppler effect. This modulation can have

350-450: Is the inphase signal, Q ( t ) {\displaystyle Q(t)} the quadrature phase signal, and j {\displaystyle j} the imaginary unit. This signal is sometimes called IQ data . In a digital modulation method, the I ( t ) {\displaystyle I(t)} and Q ( t ) {\displaystyle Q(t)} signals of each modulation symbol are evident from

375-411: Is the range of frequencies occupied by a signal that has not been modulated to higher frequencies. Baseband signals typically originate from transducers , converting some other variable into an electrical signal. For example, the electronic output of a microphone is a baseband signal that is analogous to the applied voice audio. In conventional analog radio broadcasting , the baseband audio signal

400-564: Is to use the short-time Fourier transform (STFT). However, more robust methods such as the Gabor transform or the Wigner distribution function (WVD) can be used to provide a simultaneous representation of the frequency and time domain. In all these methods, however, there will be a trade off between frequency resolution and time resolution. Once this spectral information is extracted, it can be compared to an existing database containing information about

425-454: Is used to modulate an RF carrier signal of a much higher frequency. A baseband signal may have frequency components going all the way down to the DC bias , or at least it will have a high ratio bandwidth . A modulated baseband signal is called a passband signal . This occupies a higher range of frequencies and has a lower ratio and fractional bandwidth . A baseband signal or lowpass signal

450-561: The The baseband signal is processed to obtain these coefficients, then a statistical process is used to decide which target in the database is most similar to the coefficients obtained. The choice of which features and which decision scheme to use depends on the system and application. The features used to classify a target are not limited to speech inspired coefficients. A wide range of features and detection algorithms can be used to accomplish ATR. In order for detection of targets to be automated,

475-439: The constellation diagram . The frequency spectrum of this signal includes negative as well as positive frequencies. The physical passband signal corresponds to where ω {\displaystyle \omega } is the carrier angular frequency in rad/s. A signal at baseband is often used to modulate a higher frequency carrier signal in order that it may be transmitted via radio. Modulation results in shifting

500-503: The analog telephone network. Frequency division multiplexing (FDM) allows an analog telephone wire to carry a baseband telephone call, concurrently as one or several carrier-modulated telephone calls. Digital baseband transmission, also known as line coding , aims at transferring a digital bit stream over baseband channel, typically an unfiltered wire, contrary to passband transmission, also known as carrier-modulated transmission. Passband transmission makes communication possible over

525-445: The illuminated target, such as the type of vehicle it is, the size of the target, and can potentially even distinguish biological targets. However, there are many limitations to this approach. The operator must be trained for what each target will sound like, if the target is traveling at a high speed it may no longer be audible, and the human decision component makes the probability of error high. However, this idea of audibly representing

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550-426: The signal did provide a basis for automated classification of targets. Several classifications schemes that have been developed use features of the baseband signal that have been used in other audio applications such as speech recognition . Radar determines the distance an object is away by timing how long it takes the transmitted signal to return from the target that is illuminated by this signal. When this object

575-517: The synthetic images are matters a lot when it comes to recognize the real scenes test set. The overall CNN networks structure contains 7 convolution layers, 3 max pooling layers and a Softmax layer as output. Max pooling layers are located after the second, the forth and the fifth convolution layer. A Global average pooling is also applied before the output. All convolution layers use Leaky ReLU nonlinearity activation function. Baseband In telecommunications and signal processing , baseband

600-613: The targets that the system will identify and a decision can be made as to what the illuminated target is. This is done by modeling the received signal then using a statistical estimation method such as maximum likelihood (ML), majority voting (MV) or maximum a posteriori (MAP) to make a decision about which target in the library best fits the model built using the received signal. Studies have been done that take audio features used in speech recognition to build automated target recognition systems that will identify targets based on these audio inspired coefficients. These coefficients include

625-575: Was initially done by using an audible representation of the received signal, where a trained operator who would decipher that sound to classify the target illuminated by the radar . While these trained operators had success, automated methods have been developed and continue to be developed that allow for more accuracy and speed in classification. ATR can be used to identify man-made objects such as ground and air vehicles as well as for biological targets such as animals, humans, and vegetative clutter. This can be useful for everything from recognizing an object on

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