Communication channels

The images of lesbian, gay, bisexual, and transgender people (LGBT) in Vietnam are mostly primarily transmitted to people through the largest information channel that is the mass media. This research article focuses on the two-sided interpersonal impact on the LGBT community by analyzing a case study focusing on a group of people from this community.

13p vistarlord 15-06-2023 6 3   Download

his paper presents a method for all-digital background calibration of multiple channel mismatches including offset, gain and timing mismatches in time-interleaved analog-to-digital converters (TIADCs). The average technique is used to remove offset mismatch at each channel.

11p tamynhan6 14-09-2020 16 4   Download

This dissertation aims at developing accurate and efficient approaches of 8 designing shallow UWA channel simulators based on the measurement data of the real UWA channel in a specific shallow water environment.

128p cotithanh000 07-10-2019 10 2   Download

Subspace of signal is convenional concept and very useful for applying to communication theory. In MIMO, the transmit beams can be created based on this concept, that can be predicted channel fading matrix. Here, the paper considers good subspace for transmitter can form for these beams. Moreover, the author using simulation to show higher capacity given by these beams than conventional method of creating transmit beam.

7p minhxaminhyeu4 15-07-2019 16 1   Download

The main contents of this chapter include all of the following: Communication design, map out message goals, evaluate your audience, shape message content, select channels, acquire resources, generate source credibility, eliminate design flaws, send message.

31p nomoney2 10-02-2017 47 1   Download

This paper reviews the sources of attenuation, noise and distortion encountered when communicating over AC power wiring. Various technologies which have been used to address these challenges, such as spread spectrum and digital signal processing, are then examined in light of the known channel conditions. Mời các bạn cùng tìm hiểu và tham khảo nội dung thông tin tài liệu.

17p huyen06281982 15-10-2015 49 3   Download

This thesis starts with a general introduction to power-line communication. Then an existing application, communicating on a low-voltage grid, is investigated in order to obtain some knowledge of how the power line acts as a communication channel. Mời các bạn cùng tìm hiểu để nắm bắt nội dung thông tin tài liệu.

107p huyen06281982 15-10-2015 45 12   Download

Understand the process of communication. Eliminate barriers that distort the meaning of information. Analyze the basic patterns of organizational communication. Develop the skills of organizing and running effective meetings. Master electronic forms of communication such as e-mail and know when to use them. Work with an organization’s informal communication. Improve assertive communication, presentation, nonverbal, and listening skills.

24p sonnguyen3515 19-09-2013 48 4   Download

What brought on this shift? More companies wanted to become social enterprises who engaged with their communities across all channels and departments. That kind of full-scale effort requires planning and coordination. In October we published CRM industry analyst Brent Leary’s Strategically Social: 5 Keys to Becoming a Social Business. Here are his 5 recommendations.

13p hoangliensonnhi 14-08-2013 135 11   Download

The properties of Convolutional codes. We introduced interleaving as a means to combat bursty errors by making the channel seem uncorrelated. We also studied “Concatenated codes” that simply consist of inner and outer codes. They can provide the required performance at a lower complexity.

36p doanhung_dtvtk10 24-03-2013 71 7   Download

How decoding is performed for Convolutional codes? What is a Maximum likelihood decoder? What are soft decisions and hard decisions? How does the Viterbi algorithm work?The demodulator makes a firm or hard decision whether one or zero was transmitted and provides no other information for the decoder such as how reliable the decision is.

29p doanhung_dtvtk10 24-03-2013 59 6   Download

Another class of linear codes, known as Convolutional codes. We studied the structure of the encoder and different ways for representing it.What are the state diagram and trellis representation of the code? How the decoding is performed for Convolutional codes? What is a Maximum likelihood decoder? What are the soft decisions and hard decisions? How does the Viterbi algorithm work?

28p doanhung_dtvtk10 24-03-2013 55 5   Download

Another class of linear codes, known as Convolutional codes. We study the structure of the encoder. We study different ways for representing the encoder.Convolutional codes offer an approach to error control coding substantially different from that of block codes. A convolutional encoder: encodes the entire data stream, into a single codeword. does not need to segment the data stream into blocks of fixed size (Convolutional codes are often forced to block structure by periodic truncation). is a machine with memory.

20p doanhung_dtvtk10 24-03-2013 50 5   Download

Evaluating the average probability of symbol error for different bandpass modulation schemes Comparing different modulation schemes based on their error performances.Transforming signals to improve communications performance by increasing the robustness against channel impairments (noise, interference, fading, ...)

43p doanhung_dtvtk10 24-03-2013 60 6   Download

Some bandpass modulation schemes MPAM, MPSK, MFSK, MQAM How to perform coherent and noncoherent detection.How to calculate the average probability of symbol error for different modulation schemes that we studied? How to compare different modulation schemes based on their error performances?

25p doanhung_dtvtk10 24-03-2013 74 6   Download

Another source of error due to filtering effect of the system: Intersymbol. interference (ISI) The techniques to reduce ISI. Pulse shaping to achieve zero ISI at the sampling time. Equalization to combat the filtering effect of the channel.Some bandpass modulation schemes used in DCS for transmitting information oer channel. MPAM, MPSK, MFSK, MQAM How to detect the transmitted information at the receiver. Coherent detection. Noncoherent detection.

27p doanhung_dtvtk10 24-03-2013 58 7   Download

Signal detection in AWGN channels Minimum distance detector. Maximum likelihood. Average probability of symbol error. Union bound on error probability. Upper bound on error probability based on the minimum distance.ISI in the detection process due to the filtering effects of the system Overall equivalent system transfer function

30p doanhung_dtvtk10 24-03-2013 66 6   Download

Given the observation vector , perform a mapping from to an estimate of the transmitted symbol, , such that the average probability of error in the decision is minimized.Signal vector is deterministic. Elements of noise vector are i.i.d Gaussian random variables with zeromean and variance . The noise vector pdf is

21p doanhung_dtvtk10 24-03-2013 63 6   Download

Receiver structure Impact of AWGN and ISI on the transmitted signal. Optimum filter to maximize SNR. Matched filter receiver and Correlator receiver.Demodulation and sampling: Waveform recovery and preparing the receivedl signal for detection: Improving the signal power to the noise power (SNR) using matched filter Reducing ISI using equalizerl Sampling the recovered waveform. Detection: Estimate the transmitted symbol based on the received sample

23p doanhung_dtvtk10 24-03-2013 65 8   Download

Transforming the information source to a form compatible with a digital system. Sampling. Aliasing. Quantization Uniform and non-uniform. Baseband modulation. Binary pulse modulation. M-ary pulse modulation. M-PAM (M-ary Pulse amplitude modulation).Assuming real time transmission and equal energy per transmission data bit for binary-PAM and 4-ary PAM

22p doanhung_dtvtk10 24-03-2013 71 8   Download