从这个意义上讲,数字调制和模拟调制并无本质区别。数字调制信号只须表示离散的调制状态,这些离散状态在矢量图上称为符号点 (symbol point),符号点的组合称为星座图(constellation)。 OFDM原理 - 数字调制信号完成对时间离散状态的描述 星座图和符号 星座图展示了 QAM 格式的可用符号。以 16QAM星座图为例,每个符号表示...
signal synthesis, coherent demodulation, sample sentences and string conversion, and a series of system design, the QPSK constellation diagram and the modulation and demodulation of the simulation, and the performance of the system are analyzed, and then proved the superiority of QPSK modulation techno...
sumoverxprime = sumoverxprime + ... exp(-abs(SNRaff.*(Constellation(xindex)-Constellation(xprimeindex))+x(m1)+sqrt(-1).*x(m2)).^2 ... +x(m1).^2+x(m2).^2); end C2(m1,m2)=1/(pi)*w(m1)*w(m2)*log2(sumoverxprime); end end Capforx(xindex) = sum(sum(C2,1),2...
98 grid on; 99 title('constellation of matched filter output'); 100 figure(8) 101 plot(Isam,Qsam,'X'); 102 axis([-1.2 1.2 -1.2 1.2]); 103 grid on; 104 title('constellation of sampler'); 105 figure(9) 106 subplot(211) 107 stem(final); 108 axis([0 data -2 2]); 109 grid ...
12、emodulation, sample sentences and string conversion, and a series of system design, the QPSK constellation diagram and the modulation and demodulation of the simulation, and the performance of the system are analyzed, and then proved the superiority of QPSK modulation technology.Keyword: QPSK Mo...
在一些无线通信标准中,常用相对星座误差(Relative Constellation Error)来表示EVM,这样也许更直观、更易于理解。 3、QPSK调制的测量问题 如前所述,在CDMA IS-95和cdma2000 1x最低标准中只定义了导频信道的波形质量。导频信道的波形质量固然重要,但导频+寻呼+同步+业务信道总的波形质量更具有实际意义。
func_constellation(Srx,Stx,0.5) figure; semilogy(SNR,mean(err,2),'b-o'); grid on xlabel('SNR'); ylabel('误码率'); legend('QPSK误码率'); figure plot(yfit,'-r>',... 'LineWidth',1,... 'MarkerSize',6,... 'MarkerEdgeColor','k',... ...
The design method comprises the following steps: (1) according to a 2D-QPSK constellation based on Anti-Gray mapping, generating a 3D-QPSK constellation based on Anti-Gray mapping according to the principle that the Hamming distance of the minimum Euclidean distance is greater than or equal to ...
Signal constellation distortion and BER degradation due to hardware impairments in six-port receivers with analog I/Q generation Compact and powerful, the Vyper is fully compliant to the EN302307 standard, meaning it integrates constant coding, variable coding, and adaptive coding and modulation modes...
Constellation ordering(星座图编码方式)当输入信号类型设置为Bit时,QPSK基带调制器输入信号中得每两个二进制位表示一个四进制整数,这两个二进制位既可以是自然二进制编码序列,也可以是Gray码序列,他们产生不同的星座图。当constellation or 21、dering设置为binary时,输入信号是自然二进制编码序列;当constellation ...