The 200mw Laser Pointer Performs Well In The Practical Use

By Author: longjing
Total Articles: 297
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The signal to do FFT, equivalent to the signal in the frequency axis by a close arrangement of filter banks, mainly in the following two effects: 1. Do spectrum analysis of signals, to obtain accurate target speed information; (2) to improve signal to noise ratio and the SNR, further suppress noise and clutter. In order to obtain the power spectrum of the echo signal data, FFT needs to be calculated under the Cartesian coordinate system, the plural form of transformation to polar coordinates under the modulus and phase angle representation, that is, for the complex modulo operation. Approximation based on linear approximation algorithm is suitable for short-range radar, the modulus of this highly demanding real-time, moderate precision computing applications. As the front face of the radar clutter distribution is more complex, clutter strength vary widely, if using a fixed detection threshold Blue Laser Pointer, increasing the level of interference a few decibels, it will add a large number of false alarms, which ...
... require signal processing can the use of constant false alarm (CFAR) target detection. The 200mW Laser Pointer performs well in the practical use. 

Figure 1 shows the short-range radar signal processing framework. Analog-digital conversion circuit generates the timing signal control unit, the start of the target back to the Doppler signal acquisition and A / D conversion, the target number of Doppler signals into digital signals. Time-domain data by pre-processing, is loaded into the # 1 dual-port RAM cache, and other sampling signal of N accumulated to a predetermined time, FFT module started N-point fast Fourier transform to obtain the spectrum of the N-point complex sampling. The modulus operation, the retention of information which reflects the power spectrum value data model and stored in 2 # double-port RAM. Target detection unit called 2 # RAM in the frequency domain data and analysis to identify the spectrum of the peak position, target velocity information extracted; calculated frequency-domain noise level, and adaptive threshold CFAR detection algorithm, thus completing the complex wave environment in real-time moving target detection (MTD) processing. This kind of 5mW laser pointer has several functions. 

 Import Duty of green laser pointer

FPGA and its related technology is the rapid development of modern microelectronic technology, a product of the current development of complex digital systems has become one of the main. Requires the use of a short-range radar system to detect targets in the short and being fair process, to obtain the Doppler signal spectrum analysis and complete the identification of moving target detection. Intersection of the transient signal processing system for real-time strict requirements put forward in the millisecond time range to complete the processing of the echo signal and clutter environment to identify moving objects, and gives objective speed of information processing for subsequent use; while the system in the device size, power, stringent requirements for the signal processor must be small; radar system intelligent, programmable development trend and requirements of signal processing system with reconfigurable to adapt to changing tasks and system upgrades. The general specification of green laser pointer should be met at first.

FPGA technology will be applied to short-range radar system design, construct high-performance digital signal processor, and can improve system integration, reducing the circuit scale in order to improve reliability. The general specification of 100mW laser pointer contains a lot of information.