zemax源码： This DLL models a standard ZEMAX surface type, either plane, sphere, or conic The surface also demonstrates a user-defined apodization filter The filter is defined as part of the real ray trace, case 5 The filter can be used at the stop to produce x-y Gaussian apodization similar to the Gaussian pupil apodization in ZEMAX but separate in x and y. The amplitude apodization is of the form EXP[-(Gx(x/R)^2 + Gy(y/R)^2)] The transmission is of the form EXP[-2(Gx(x/R)^2 + Gy(y/R)^2)] where x^2 + y^2 = r^2 R = semi-diameter The tranmitted intensity is maximum in the center. T is set to 0 if semi-diameter < 1e-10 to avoid Division by zero.
标签： standard surface models either
上传时间： 2013-12-05
上传用户：003030
This paper investigates the design of joint frequency offset and carrier phase estimation of a multi-frequency time Division multiple access (MF-TDMA) demodulator that is applied to a digital video broadcasting—return channel system via satellite (DVB-RCS). The proposed joint estimation algorithm is based on the interpolation technique for two correlation values in the frequency and phase domains. This simple interpolation technique can significantly improve frequency and phase resolution capabilities of the proposed technique without increasing the number of the correlation values. In addition, the overall block diagram of a digital communications receiver for DVB-RCS is presented, which was designed using the proposed estimation algorithms. Index Terms—Carrier phase estimation, DVB-RCS, frequency offset estimation, interpolation, joint estimation, MF-TDMA.
标签： investigates estimation frequency carrier
上传时间： 2015-12-30
上传用户：ls530720646
This paper considers semiblind channel estimation and data detection for orthogonal frequency-Division multiplexing (OFDM) over frequency-selective fading channels.
标签： frequency-divis estimation orthogonal considers
上传时间： 2014-12-07
上传用户：coeus
This project aim was to build wireless software modem for data communication between two computers using an acoustic interface in the voice frequency range (20Hz– 20,000Hz). The transmitting antenna is a speaker (frequency response of: 90Hz – 20,000Hz) and the receiving antenna is a microphone (frequency response of: 100Hz – 16,000Hz). The test files used as information files were text files. This goal was attained both in an incoherent scheme and in a coherent scheme. Build under Matlab code, our modem uses OFDM (orthogonal frequency Division multiplexing) modulation, synchronization by LMS sequence, channel estimation (no equalizer) via pilot tones. The symbols are either PSK or ASK for a constellation size of 2 or 4. To optimize the probability of error, these symbols were mapped using Gray mapping. Report
标签： communication computers software wireless
上传时间： 2014-05-29
上传用户：wangdean1101
Summary: Newton-Raphson method for all real roots of the polynomial. MATLAB Release: R11 Description: This M-file calculates all the real roots of the given polynomial. It calls syn_Division, a synthetic Division function, and derivate, differentiation function.
标签： Newton-Raphson polynomial Summary Descrip
上传时间： 2013-12-24
上传用户：cccole0605
OFDM Modem Applications • Digital Video Broadcast (DVB) • Digital Audio Broadcast (DAB) • Broadband Wireless Access (802.16x) • Wireless LAN (802.11x & HiperLAN) Orthogonal OFDM Sub-carriers Orthogonal Frequency Division Multiplexing (OFDM)
标签： Broadcast Digital 8226 Applications
上传时间： 2016-03-23
上传用户：cc1
The WCDMA Physical Layer Demo consists of an end-to-end (transmitter-to-receiver) simulation of the Frequency Division Duplex (FDD) Downlink physical layer for several Dedicated Channels (DCH) as specified by the 3GPP standard (Release 99).
标签： transmitter-to-receiver end-to-end simulation Physical
上传时间： 2013-11-28
上传用户：gdgzhym
In this project we analyze and design the minimum mean-square error (MMSE) multiuser receiver for uniformly quantized synchronous code Division multiple access (CDMA) signals in additive white Gaussian noise (AWGN) channels.This project is mainly based on the representation of uniform quantizer by gain plus additive noise model. Based on this model, we derive the weight vector and the output signal-to-interference ratio (SIR) of the MMSE receiver. The effects of quantization on the MMSE receiver performance is characterized in a single parameter named 鈥漞quivalent noise variance鈥? The optimal quantizer stepsize which maximizes the MMSE receiver output SNR is also determined.
标签： mean-square multiuser receiver project
上传时间： 2014-11-21
上传用户：ywqaxiwang
The UMTS Physical Layer model consists of an end-to-end (transmitter-to-receiver) simulation of the Frequency Division Duplex (FDD) Downlink physical layer for several Dedicated Channels (DCH) as specified by the 3GPP standard (Release 99).
标签： transmitter-to-receiver end-to-end simulation Physical
上传时间： 2014-01-11
上传用户：it男一枚
OFDM(Orthogonal Frequency Division Multiplexing)即正交频分复用技术，实际上OFDM是多载波调制的一种。其主要思想是：将信道分成若干正交子信道，将高速数据信号转换成并行的低速子数据流，调制到在每个子信道上进行传输。正交信号可以通过在接收端采用相关技术来分开，这样可以减少子信道之间的相互干扰 ICI 。每个子信道上的信号带宽小于信道的相关带宽，因此每个子信道上的可以看成平坦性衰落，从而可以消除符号间干扰。而且由于每个子信道的带宽仅仅是原信道带宽的一小部分，信道均衡变得相对容易。
标签： OFDM
上传时间： 2015-02-17
上传用户：hongyun288
