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From the Top Down: The Physical Layer–FM OFDM
Published in David P. Maxson, The IBOC Handbook, 2007
When a point in the constellation is plotted on the complex plane, the result is a constellation diagram. Figure 7.4 reveals the structure of a constellation diagram. A QPSK-modulated subcarrier has four possible ideal phase and amplitude points, one for each value of the symbol. Note how, ideally, these points target four positions that are at odd multiples of 45 degrees or P/4 radians with respect to the I and Q axes. This is the result of the combining of the various pairs of quadrature signals shown in Tables 7.4 and 7.5.
Predistortion Algorithms and Applications
Published in Jingchang Nan, Mingming Gao, Nonlinear Modeling Analysis and Predistortion Algorithm Research of Radio Frequency Power Amplifiers, 2021
The constellation diagram is a vector diagram showing the co-directional component (horizontal coordinate axis) versus orthogonal component (vertical coordinate axis) of the signal to represent signal characteristics. Figures 10.37 shows the constellation diagrams of output signals when the input signal directly goes through the PA and goes in presence of FLUT predistortion or improved predistortion method, plus the constellation diagram of the original signal.
WLAN Technology Basics
Published in Rihai Wu, Xun Yang, Xia Zhou, Yibo Wang, Enterprise Wireless Local Area Network Architectures and Technologies, 2021
Rihai Wu, Xun Yang, Xia Zhou, Yibo Wang
A constellation diagram uses polar coordinates, with each point represented by an angle and distance from the point to the origin, which correspond to the phase and the amplitude by which QAM is implemented, respectively.
Novel calibration algorithm of six-port receivers based on radial basis function network
Published in International Journal of Electronics, 2023
Qing Wang, Yongle Wu, Yue Qi, Weimin Wang, Qinghua Yang
It can be seen from the test results that the smaller ρ is, the more accurate the prediction result is. However, when ρ is small, the training time increases. It is equivalent to exchanging time and operation volume for operation precision. The constellation diagram can intuitively represent the relationship between the transmitted signal and the received signal. The constellation diagram of the data tested using this network architecture is shown in Figure 5, and Figure 6 shows a constellation plot of the ideal baseband signal sent. In addition, Table 2 shows the comparison between this algorithm and the previous algorithm. From the comparison, it can be seen that the accuracy of the algorithm is greatly improved compared with the previous work.
Signal integrity analysis on a microstrip ultra-wideband coupled-line coupler
Published in International Journal of Electronics, 2019
Saffrine Kingsly, Sangeetha Velan, Malathi Kanagasabai, Sangeetha Subbaraj, Yogeshwari Panneer Selvam, Bhuvaneswari Balasubramaniyan
A constellation diagram is a graphical mapping of each possible signal on a scatter plot in the complex plane at symbol sampling time. As the impairments increase the noise level increases which makes the symbol point appear as a cluster instead of a dot. The constellation diagrams at two desired frequencies are ordered in Figures 9 and Figure 10. In both the figures, a and d shows the ideal condition where the signal generator is directly connected to the receiver. Figures b and e show the plots when the signal generator is connected to the input port (Port 1) and the signal analyser is connected to the transmitting port (Port 2).