ACPR (adjacent channel power ratio), AltCPR (alternatechannel power ratio), and noise are important performancemetrics for digital communication systems thatuse, for example, WCDMA (wideband code division multipleaccess) modulation. ACPR and AltCPR are bothmeasures of spectral regrowth. The power in the WCDMAcarrier is measured using a 5MHz MEASUREMENT bandwidth;see Figure 1. In the case of ACPR, the total powerin a 3.84MHz bandwidth centered at 5MHz (the carrierspacing) away from the center of the outermost carrier ismeasured and compared to the carrier power. The resultis expressed in dBc. For AltCPR, the procedure is thesame, except we center the MEASUREMENT 10MHz awayfrom the center of the outermost carrier.
Accurate MEASUREMENT of the third order intercept pointfor low distortion IC products such as the LT5514 requirescertain precautions to be observed in the test setup andtesting procedure. The LT5514 linearity performance ishigh enough to push the test equipment and test set-up totheir limits. A method for accurate MEASUREMENT of thirdorder intermodulation products, IM3, with standard testequipment is outlined below.It is also important to correctly interpret the LT5514specification with respect to ROUT, and the impact ofdemo-board transmission-line termination loss whenevaluating the linearity performance, as explained in theLT5514 Datasheet and in Note 1 of this document.
系統(tǒng)下,地球坐標(biāo)轉(zhuǎn)換的源代碼,在WGS-84坐標(biāo)和北京54坐標(biāo)之間的一套轉(zhuǎn)換參數(shù),可以全國(guó)通用的，在每個(gè)地方會(huì)不一樣，因?yàn)樗鼈兪莾蓚€(gè)不同的橢球基準(zhǔn)。 // WGS2GK.CPP : C++ version of Ottmar Labonde s WGSDHDN3.PAS with CPU time MEASUREMENT // compile with MS Visual C++ version 6.0 or do the necessary modifications for your compiler // // Conversion of
一個(gè)非常好的時(shí)間序列工具箱，詳細(xì)使用說(shuō)明見(jiàn)P. M. T. Broersen, Automatic Spectral Analysis with Time Series Models, IEEE Transactions on Instrumentation and MEASUREMENT, Vol. 51, No. 2, April 2002, pp. 211-216.
A self-designed control of PC parallel port communication is introduced in this paper.Taking advantage of the MFC ActiveX technology, it is developed in Visual C++ and offset the scarcity of the control of PC parellel paort communication. An example of frequency MEASUREMENT shows the detail procedure and application of the control.
To estimate the input-output mapping with inputs x
％ and outputs y generated by the following nonlinear,
％ nonstationary state space model:
％ x(t+1) = 0.5x(t) + [25x(t)]/[(1+x(t))^(2)]
％ + 8cos(1.2t) + process noise
％ y(t) = x(t)^(2) / 20 + 6 squareWave(0.05(t-1)) + 3
％ + time varying MEASUREMENT noise
％ using a multi-layer perceptron (MLP) and both the EKF and
％ the hybrid importance-samping resampling (SIR) algorithm.
To fully utilize the available spectrum for a wireless communication
system it is feasible to adapt to different situations
on the channel. In this paper a flexible OFDM
transmitter is presented together with basic theory behind
OFDM transmission. It is shown that high flexibility can
be obtained with a reasonable amount
Flexible baseband transmitter for OFDM
of additional hardware.
Part of the design, the FFT-processor, has already
been fabricated and MEASUREMENT results are presented.
