Mobile operators must continuously pursue cost‐ effective and efficient solutions to meet the high data demand requirements of their subscribers. Limited spectrum allocations and non‐contiguous spectrum blocks continue to pose challenges for mobile operators supporting large data uploads and downloads across their networks. With the increase in video and social media content, the challenges have increased exponentially.
標簽： qorvo-carrier-aggregation-fundame ntals
上傳時間： 2020-05-31
上傳用戶：shancjb
LTE-Advanced becomes a truly global standard for 4G cellular communications. Relay, as one of the key technologies of LTE-Advanced, can significantly extend the coverage, and improve the system throughput. LTE-A standards and tech- nologies were described in several recent books where the limited pages for relay feature prevent the detailed explanations of the technology. In this book, we tried to provide an in-depth description of LTE-A relay development. More specifically, significant portions are spent on relay channel modeling and potential technologies during the study item phase of the development, although some of those tech- nologies, such as Type 2 cooperative relay, multi-hop relay, relay with backhaul of carrier aggregation, were not standardized in Release 10 LTE.
標簽： LTE-Advanced Technology Relay
上傳時間： 2020-05-27
上傳用戶：shancjb
Carrier & Symbol Timing Recovery
標簽： Recovery Carrier Symbol Timing
上傳時間： 2014-01-12
上傳用戶：蠢蠢66
Single Carrier Frequency Domain Equalization Simulation(單載波頻域均衡仿真程序)
標簽： Equalization Simulation Frequency Carrier
上傳時間： 2015-10-17
上傳用戶：asdfasdfd
We address the problem of blind carrier frequency-offset (CFO) estimation in quadrature amplitude modulation, phase-shift keying, and pulse amplitude modulation communications systems.We study the performance of a standard CFO estimate, which consists of first raising the received signal to the Mth power, where M is an integer depending on the type and size of the symbol constellation, and then applying the nonlinear least squares (NLLS) estimation approach. At low signal-to noise ratio (SNR), the NLLS method fails to provide an accurate CFO estimate because of the presence of outliers. In this letter, we derive an approximate closed-form expression for the outlier probability. This enables us to predict the mean-square error (MSE) on CFO estimation for all SNR values. For a given SNR, the new results also give insight into the minimum number of samples required in the CFO estimation procedure, in order to ensure that the MSE on estimation is not significantly affected by the outliers.
標簽： frequency-offset estimation quadrature amplitude
上傳時間： 2014-01-22
上傳用戶：牛布牛
Carrier-phase synchronization can be approached in a general manner by estimating the multiplicative distortion (MD) to which a baseband received signal in an RF or coherent optical transmission system is subjected. This paper presents a unified modeling and estimation of the MD in finite-alphabet digital communication systems. A simple form of MD is the camer phase exp GO) which has to be estimated and compensated for in a coherent receiver. A more general case with fading must, however, allow for amplitude as well as phase variations of the MD. We assume a state-variable model for the MD and generally obtain a nonlinear estimation problem with additional randomly-varying system parameters such as received signal power, frequency offset, and Doppler spread. An extended Kalman filter is then applied as a near-optimal solution to the adaptive MD and channel parameter estimation problem. Examples are given to show the use and some advantages of this scheme.
標簽： synchronization Carrier-phase multiplicativ approached
上傳時間： 2013-11-28
上傳用戶：windwolf2000
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
demodulates the FM modulated signal Y at the carrier frequency Fc (Hz). Y and Fc have sample frequency Fs (Hz). FREQDEV is the frequency deviation (Hz) of the modulated signal.
標簽： demodulates the modulated frequency
上傳時間： 2014-01-06
上傳用戶：皇族傳媒
uses the message signal X to modulate the carrier frequency Fc (Hz) and sample frequency Fs (Hz), where Fs > 2*Fc. FREQDEV (Hz) is the frequency deviation of the modulated signal.
標簽： frequency the modulate message
上傳時間： 2016-01-20
上傳用戶：569342831
Comparison of the performances of the LS and the MMSE channel estimators for a 64 sub carrier OFDM system based on the parameter of Mean square error
標簽： the performances Comparison estimators
上傳時間： 2016-02-01
上傳用戶：hgy9473
