zemax源碼： 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.
標簽： standard surface models either
上傳時間： 2013-12-05
上傳用戶：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.
標簽： investigates estimation frequency carrier
上傳時間： 2015-12-30
上傳用戶：ls530720646
This paper considers semiblind channel estimation and data detection for orthogonal frequency-Division multiplexing (OFDM) over frequency-selective fading channels.
標簽： frequency-divis estimation orthogonal considers
上傳時間： 2014-12-07
上傳用戶：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
標簽： communication computers software wireless
上傳時間： 2014-05-29
上傳用戶：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.
標簽： Newton-Raphson polynomial Summary Descrip
上傳時間： 2013-12-24
上傳用戶：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)
標簽： Broadcast Digital 8226 Applications
上傳時間： 2016-03-23
上傳用戶：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).
標簽： transmitter-to-receiver end-to-end simulation Physical
上傳時間： 2013-11-28
上傳用戶：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.
標簽： mean-square multiuser receiver project
上傳時間： 2014-11-21
上傳用戶：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).
標簽： transmitter-to-receiver end-to-end simulation Physical
上傳時間： 2014-01-11
上傳用戶：it男一枚
OFDM(Orthogonal Frequency Division Multiplexing)即正交頻分復用技術，實際上OFDM是多載波調制的一種。其主要思想是：將信道分成若干正交子信道，將高速數據信號轉換成并行的低速子數據流，調制到在每個子信道上進行傳輸。正交信號可以通過在接收端采用相關技術來分開，這樣可以減少子信道之間的相互干擾 ICI 。每個子信道上的信號帶寬小于信道的相關帶寬，因此每個子信道上的可以看成平坦性衰落，從而可以消除符號間干擾。而且由于每個子信道的帶寬僅僅是原信道帶寬的一小部分，信道均衡變得相對容易。
標簽： OFDM
上傳時間： 2015-02-17
上傳用戶：hongyun288
