qam modulation

. When the upper type is not equal to zero, the phase of the PLL is not locked, and the frequency of the input signal and the output signal are different, and U C (t) changes with time. As shown in Fig. 8-4-3, the voltage-controlled oscillator is characterized by the oscillation frequency of the voltage-controlled oscillator ωu is centered on the ω0 and varies with the input signal voltage u C (t). The expression for this attribute is (8-4-6) that when u C (t) changes with time, the oscillation

is also my first experience with microcontrollers),I was a little surprised so analogwrite didn ' t actually output a voltage, but a PWM (pulse-width modulated) sig Nal.After all, the ATmega had a a-d (analog to digital) converter along with Arduino ' sanalogread.The complementaryanalogwrite function is there, but no d-a (digital to analog) converter on the AVR chip itself.Fortunately, there is an easy-to-convert a PWM signal to a analog voltage.Need to implement a simple single-pole low pass f

capabilities of the host machine to complete the GPS function. It is expected that GPS receivers of similar architectures will gradually become mainstream in the market due to their low overall cost. The architecture is a two-step sub-frequency super-external receiver, and the output is a digital Second Intermediate Frequency Signal Stream. In addition to the RF input filter, an intermediate frequency output filter, and a phase-locked loop filter, the filter must be set up on the chip. The MAX2

HSDPA (High speed downlink packet access) is used to realize high speed downlink data service of WCDMA network, which can make the downlink data rate reach 8~10mbps, which is regarded as the main solution of the 3G era. The data rate can reach 20Mbps in the HSDPA system with multiple and multiple out (MIMO) technology. The emergence of HSDPA has aroused great concern of the industry. As the following evolution technology of WCDMA system, many key technologies in HSDPA are similar to CDMA20001XEV

images with small images and low image quality can be transmitted; images with dozens or more frames can be transmitted per second, and the animation effect is very obvious and there is a delay, real-time Monitoring fails. 4. microwave transmission: It is one of the solutions to solve the problem of video surveillance transmission in a location that is difficult to connect several kilometers or even dozens of kilometers. The image is carried to a high-frequency carrier and converted to a high-f

The multimedia is suspended. Let's talk about a few irrelevant theme words. Although it can behave like nothing, it is quite lost. I have never believed that scores can be used to measure a person's level or something, but I still have a bottom line on my requirements. The bottom line is that I stick to my own style of capital. Over the bottom line, all justified reasons will turn into the arrogant requirements of the 80 s. Why have I fallen to the point where I am not involved? How can I spend

In the field of electronic communication,Baud Rate (Baudrate) that isModulation rateIndicates the unit time after the signal is modulated.PorterNumber, that is, the number of times the carrier parameter changes within the unit time. It is a measure of the symbolic transmission rate. Generally, the unit is "Porter per second" (BPS, 1 port transfers 1 Symbol per second (may contain multiple bits ). The rate of the analog line signal, also known as the modulati