-
The 4.0 kbit/s speech codec described in this paper is based on a
Frequency Domain Interpolative (FDI) coding technique, which
belongs to the class of prototype waveform Interpolation (PWI)
coding techniques. The codec also has an integrated voice
activity detector (VAD) and a noise reduction capability. The
input signal is subjected to LPC analysis and the prediction
residual is separated into a slowly evolving waveform (SEW) and
a rapidly evolving waveform (REW) components. The SEW
magnitude component is quantized using a hierarchical
predictive vector quantization approach. The REW magnitude is
quantized using a gain and a sub-band based shape. SEW and
REW phases are derived at the decoder using a phase model,
based on a transmitted measure of voice periodicity. The spectral
(LSP) parameters are quantized using a combination of scalar
and vector quantizers. The 4.0 kbits/s coder has an algorithmic
delay of 60 ms and an estimated floating point complexity of
21.5 MIPS. The performance of this coder has been evaluated
using in-house MOS tests under various conditions such as
background noise. channel errors, self-tandem. and DTX mode
of operation, and has been shown to be statistically equivalent to
ITU-T (3.729 8 kbps codec across all conditions tested.
標簽：
frequency-domain
interpolation
performance
Design
kbit_s
speech
coder
based
and
of
上傳時間：
2018-04-08
上傳用戶：kilohorse
-
DESCRIPTION
The Texas Instruments MSP430 family of ultra-low-power microcontrollers consists of several devices featuring
different sets of peripherals targeted for various applications. The architecture, combined with five low-power
modes, is optimized to achieve extended battery life in portable measurement applications. The device features a
powerful 16-bit RISC CPU, 16-bit registers, and constant generators that contribute to maximum code efficiency.
The digitally controlled oscillator (DCO) allows wake-up from low-power modes to active mode in less than 1 μs.
The MSP430G2x13 and MSP430G2x53 series are ultra-low-power mixed signal microcontrollers with built-in 16-
bit timers, up to 24 I/O capacitive-touch enabled pins, a versatile analog comparator, and built-in communication
capability using the universal serial communication interface. In addition the MSP430G2x53 family members
have a 10-bit analog-to-digital (A/D) converter. For configuration details see Table 1.
Typical applications include low-cost sensor systems that capture analog signals, convert them to digital values,
and then process the data for display or for transmission to a host system.
標簽：
G2553
2553
430G
MSP
430
上傳時間：
2018-12-25
上傳用戶：ygyh
-
% Computation of ST-ZCR and STE of a speech signal.
%
% Functions required: zerocross, sgn, winconv.
%
% Author: Nabin Sharma
% Date: 2009/03/15
[x,Fs] = wavread('so.wav'); % word is: so
x = x.';
N = length(x); % signal length
n = 0:N-1;
ts = n*(1/Fs); % time for signal
% define the window
wintype = 'rectwin';
winlen = 201;
winamp = [0.5,1]*(1/winlen);
標簽：
短時過零率和短時能量
上傳時間：
2019-09-23
上傳用戶：minwenji
-
ephraim1995 子空間降噪經典算法
標簽：
Enhancement
Approach
Subspace
Signal
Speech
for
上傳時間：
2020-04-29
上傳用戶：LacrimosaMozart
-
The concept of smart cities emerged few years ago as a new vision for urban
development that aims to integrate multiple information and communication
technology (ICT) solutions in a secure fashion to manage a city’s assets. Modern ICT
infrastructure and e-services should fuel sustainable growth and quality of life,
enabled by a wise and participative management of natural resources to be ensured
by citizens and government. The need to build smart cities became a requirement that
relies on urban development that should take charge of the new infrastructures for
smart cities (broadband infrastructures, wireless sensor networks, Internet-based
networked applications, open data and open platforms) and provide various smart
services and enablers in various domains including healthcare, energy, education,
environmental management, transportation, mobility and public safety.
標簽：
Enablers
Cities
Smart
for
上傳時間：
2020-05-25
上傳用戶：shancjb
-
The Internet of Things is considered to be the next big opportunity, and challenge, for the
Internet engineering community, users of technology, companies and society as a whole. It
involves connecting embedded devices such as sensors, home appliances, weather stations
and even toys to Internet Protocol (IP) based networks. The number of IP-enabled embedded
devices is increasing rapidly, and although hard to estimate, will surely outnumber the
number of personal computers (PCs) and servers in the future. With the advances made over
the past decade in microcontroller,low-power radio, battery and microelectronic technology,
the trend in the industry is for smart embedded devices (called smart objects) to become
IP-enabled, and an integral part of the latest services on the Internet. These services are no
longer cyber, just including data created by humans, but are to become very connected to the
physical world around us by including sensor data, the monitoring and control of machines,
and other kinds of physical context. We call this latest frontier of the Internet, consisting of
wireless low-power embedded devices, the Wireless Embedded Internet. Applications that
this new frontier of the Internet enable are critical to the sustainability, efficiency and safety
of society and include home and building automation, healthcare, energy efficiency, smart
grids and environmental monitoring to name just a few.
標簽：
Embedded
Internet
Wireless
6LoWPAN
The
上傳時間：
2020-05-26
上傳用戶：shancjb
-
This introduction takes a visionary look at ideal cognitive radios (CRs) that inte-
grate advanced software-defined radios (SDR) with CR techniques to arrive at
radios that learn to help their user using computer vision, high-performance
speech understanding, global positioning system (GPS) navigation, sophisticated
adaptive networking, adaptive physical layer radio waveforms, and a wide range
of machine learning processes.
標簽：
Technology
Cognitive
Radio
上傳時間：
2020-05-26
上傳用戶：shancjb
-
The telecommunications industry is undoubtedly in a period of radical change with
the advent of mobile broadband radio access and the rapid convergence of Internet
and mobile services. Some of these changes have been enabled by a fundamental
shift in the underlying technologies; mobile networks are now increasingly based
on a pure Internet Protocol (IP) network architecture. Since the first edition of this
book was published in 2009, a multitude of connected devices from eBook readers
to smartphones and even Machine-to-Machine (M2M) technologies have all started
to benefit from mobile broadband. The sea change over the last few years is only the
beginning of a wave of new services that will fundamentally change our economy, our
society, and even our environment. The evolution towards mobile broadband is one of
the core underlying parts of this revolution and is the focus of this book.
標簽：
Networks
Packet
EPC
and
4G
上傳時間：
2020-05-27
上傳用戶：shancjb
-
Transmit power in wireless cellular networks is a key degree of freedom
in the management of interference, energy, and connectivity. Power
control in both uplink and downlink of a cellular network has been
extensively studied, especially over the last 15 years, and some of the
results have enabled the continuous evolution and significant impact of
the digital cellular technology.
標簽：
Cellular
Networks
Wireless
Control
Power
in
上傳時間：
2020-05-31
上傳用戶：shancjb
-
Quality of Service ( QoS ) has always been in a world of its own, but as the technology
has been refi ned and has evolved in recent years, QOS usage has increased to the point
where it is now considered a necessary part of network design and operation. As with
most technologies, large - scale deployments have led to the technology becoming more
mature, and QOS is no exception.
標簽：
QOS-Enabled
Networks
上傳時間：
2020-05-31
上傳用戶：shancjb
