orthogonal signal correction.

In order to improve the interpretability of the PLS model,the orthogonal signal correction(OSC) data preprocessing method is introduced,then the OSC-PLS model for dam safety monitoring,which can preprocess original independent variables and remove signals unrelated to dependent variables,is proposed.

According to previous dam safety monitoring statistic models and focus on the defects of least square regression statistic theory, the statistic models for dam safety monitoring were put forward in the dissertation based on the partial least square square regression, orthogonal signal correction, weighted block recursive partial least squares regression, neural network.

Firstly a signal period is divided into eight equal segments based on polarity and amplitude of orthogonal signals.

In this paper,the bit error performance of the M-ary orthogonal signals in conjunction with transmit selection combined with receive maximum ratio combining over Nakagami fading channels.

By transmitting orthogonal signals,virtual subarrays are designed through filters,and the Subarrays Selection(SAS) algorithm is proposed.

Design of DDS orthogonal signal source based on CPLD

Two channels of orthogonal signal generated by FPGA and 12 bit D/A,one is taken as the reference signal for multiplier I and also stir the system to detect the real part of the system response.

To obtain quadrature signals with the rigid amplitude and phase balances, an optimum digital Hilbert transforming method using the minimax criterion is provided.

There exists the imbalance of amplitude and phase between the pair of quadrature signals, which leads to the crosstalk between the forward and reverse blood flow information.