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
在包 hugeinteger 中創建功能類 HugeInteger，該類用來存放和操作一個不超過 40 位的大整數。 (1) 定義一個構造函數，用來對大整數進行初始化。參數為一個字符串。 (2) 定義 input 成員函數，實現大整數的重新賦值。參數為一個字符串，無返回 值。 (3) 定義 output 成員函數，將大整數輸出到屏幕上。無參數無返回值。 (4) 定義 add 成員函數，實現兩個大整數的加法。參數為一個 HugeInteger 對 象，無返回值，例如： HugeInteger A = new HugeInteger("12345"); HugeInteger B = new HugeInteger("1234"); A.add(B); 此時，A 為 13579，B 為 1234。 (5) 定義 sub 成員函數，實現兩個大整數的減法。參數和返回值同 add 函數。 (6) 定義若干大整數關系運算的成員函數，包括 isEqualTo（等于，=）、 isNotEqualTo（不等于，≠）、isGreaterThan（大于，>）、isLessThan（小 于，<）、isGreaterThanOrEqualTo（大于等于，≥）和 isLessThanOrEqualTo （小于等于，≤）。這些函數的參數為一個 HugeInteger 對象，返回值為一個 布爾類型，表示關系運算的結果，例如： HugeInteger A = new HugeInteger("12345"); HugeInteger B = new HugeInteger("1234"); 那么此時 A.isGreaterThan(B)的結果應當為 True，表示 12345>1234。
上傳時間： 2019-06-01
上傳用戶：idealist
Sub 大小寫修正與符號去除()
上傳時間： 2019-07-09
上傳用戶：tkhahah
transimpedance linearization circuitry. This allows it to drive video loads with excellent differential gain and phase perfor mance on only 50 mW of power. The AD8001 is a current feedback amplifier and features gain flatness of 0.1 dB to 100 MHz while offering differential gain and phase error of 0.01% and 0.025°. This makes the AD8001 ideal for professional video electronics such as cameras and video switchers. Additionally, the AD8001’s low distortion and fast settling make it ideal for buffer high-speed A-to-D converters. The AD8001 offers low power of 5.5 mA max (VS = ±5 V) and can run on a single +12 V power supply, while being capable of delivering over 70 mA of load current. These features make this amplifier ideal for portable and battery-powered applications where size and power are critical. The outstanding bandwidth of 800 MHz along with 1200 V/μs of slew rate make the AD8001 useful in many general purpose high-speed applications where dual power supplies of up to ±6 V and single supplies from 6 V to 12 V are needed. The AD8001 is available in the industrial temperature range of –40°C to +85°C.
上傳時間： 2020-04-21
上傳用戶：su1254
Two important microwave remote sensors are the radar and the radiometer. There have been a number of books written on various aspects of radar, but there have been only a few written on microwave radiometers, especially on sub- jects of how to design and build radiometer systems. This book, which is the second edition of a book originally published in 1989, attempts to fill this void.
標簽： Radiometer Microwave Systems
上傳時間： 2020-05-23
上傳用戶：shancjb
Two important microwave remote sensors are the radar and the radiometer. There have been a number of books written on various aspects of radar, but there have been only a few written on microwave radiometers, especially on sub- jects of how to design and build radiometer systems. This book, which is the second edition of a book originally published in 1989, attempts to fill this void.
標簽： Radiometer Microwave Analysis Systems Design
上傳時間： 2020-05-26
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 book is intended to help electric power and telephone company personnel and individuals interested in properly protecting critical tele- communications circuits and equipment located in high voltage (HV) environments and to improve service reliability while maintaining safe working conditions. Critical telecommunications circuits are often located in HV environments such as electric utility power plants, substations, cell sites on power towers, and standalone telecommuni- cations facilities such as 911 call centers and mountaintop telecom- munications sites.
標簽： Protection Voltage High
上傳時間： 2020-05-27
上傳用戶：shancjb
This book is intended for the graduate or advanced undergraduate engineer. The primary motivation for developing the text was to present a complete tutorial of phase-locked loops with a consistent notation. I believe this is critical for the practicing engineer who uses the text as a self-study guide.
標簽： Communications Phase-Locked Wireless Loops for
上傳時間： 2020-05-31
上傳用戶：shancjb
In a cellular communication system, a service area or a geographical region is divided into a number of cells, and each cell is served by an infrastructure element called the base station through a radio interface. Management of radio interface related resources is a critical design component in cellular communications.
標簽： Management Resource Radio
上傳時間： 2020-06-01
上傳用戶：shancjb
