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.
标签： frequency-domain interpolation performance Design kbit_s speech coder based and of
上传时间： 2018-04-08
上传用户：kilohorse
本系统以TMS320F2812为核心设计了一种智能家居装置——“随叫随到”垃圾桶，实现了语音控制垃圾桶的运动。以拾音器作为声音传感器，采用延时估计法（Time Delay Estimation，TDE）实现了声源方位的实时检测；采用超声波传感器实现了垃圾桶行进的蔽障功能；同时，采用语音识别技术实现了对用户的前、后、左、右行驶或开启、关闭垃圾桶盖等各种语音指示的识别。从而达到了垃圾桶“随叫随到”的智能化、人性化的目的。
标签： 比赛
上传时间： 2018-10-17
上传用户：cyyyyyy
Optimal Guaranteed Cost Sliding-Mode Control of Interval Type-2 Fuzzy Time-Delay Systems
上传时间： 2019-07-24
上传用户：sjjy0220
This book addresses two aspects of network operation quality; namely, resource management and fault management. Network operation quality is among the functions to be fulfilled in order to offer quality of service, QoS, to the end user. It is characterized by four parameters: – packet loss; – delay; – jitter, or the variation of delay over time; – availability. Resource management employs mechanisms that enable the first three parameters to be guaranteed or optimized. Fault management aims to ensure continuity of service.
标签： Ethernet Networks MPLS and IP
上传时间： 2020-05-27
上传用户：shancjb
It is more than a decade since GSM was first commercially available. After some unexpected delay, it seems that finally UMTS is here to stay as a 3G system standardised by 3GPP, at least for another ten years. UMTS will enable multi-service, multi-rate and flexible IP native-based mobile technologies to be used in wide area scenarios and also pave the way for a smooth transition from circuit switched voice networks to mobile packet services.
标签： Management Strategies Resource Radio
上传时间： 2020-06-01
上传用户：shancjb
Mobile radio communications are evolving from pure telephony systems to multimedia platforms offering a variety of services ranging from simple file transfers and audio and video streaming, to interactive applications and positioning tasks. Naturally, these services have different constraints concerning data rate, delay, and reliability (quality-of-service (QoS)). Hence, future mobile radio systems have to provide a large flexibility and scal- ability to match these heterogeneous requirements.
标签： Communications Wireless Channels MIMO over
上传时间： 2020-06-01
上传用户：shancjb
With the proliferation of cloud computing and Internet online services, more and more data and computation are migrated to geographical distributed Internet data centers (IDCs), which can provide reliability, management, and cost benefits. However, IDC operators encounter several major problems in IDC operations, such as huge energy consumption and energy cost, and high carbon emission. To deal with the above problems, IDC operators have to efficiently manage the way of energy consumption and energy supply. Considering the potential of smart grid, we focus on the energy management of IDCs in smart grid from several perspectives, i.e., power outage, carbon emission, heterogeneous service delay guarantees, and operation risk.
上传时间： 2020-06-07
上传用户：shancjb
In this chapter we give a quick overview of control theory, explaining why integral feedback control works, describing PID controllers, and summariz- ing some of the currently available techniques for PID controller design. This background will serve to motivate our results on PID control, pre- sented in the subsequent chapters.
标签： Controllers Time-Delay Systems PID for
上传时间： 2020-06-10
上传用户：shancjb
STM32F407VGT6精确脉冲控制步进电机源码,采用STM32F407VGT6芯片，抛弃单脉冲输出方式，直接使用普通PWM输出方式精确输出脉冲个数，每个脉冲都可以改变频率和占空比。PWM+中断，简单粗暴。#include "sys.h"#include "delay.h"#include "pwm1.h"#include "pwm2.h"#include "pwm3.h"//注释见pwm1.c文件extern int count2;int main(void){ delay_init(168); //初始化延时函数 TIM2_Init(1,167); TIM3_Init(1,167); TIM5_Init(1,167); // delay_ms(1000); TIM2_OUTPUT(); TIM3_OUTPUT(); TIM5_OUTPUT(); while(1) { //TIM2每次输出完10个脉冲后间隔100ms再次输出 if(count2 >= 10){ delay_ms(100); TIM2_OUTPUT(); } }
标签： stm32f407vgt6 脉冲控制 步进电机
上传时间： 2021-10-26
上传用户：xsr1983
include<reg52.h> #define uint unsigned int #define uchar unsigned char uint temp,aa,wang,qian,bai,shi,ge; sbit dula=P2^6; sbit wela=P2^7; uchar code table[]={ 0x3f,0x06,0x5b,0x4f, 0x66,0x6d,0x7d,0x07, 0x7f,0x6f,0x77,0x7c, 0x39,0x5e,0x79,0x71}; void display( uint wang,uint qian,uint bai,uint shi,uint ge); void delay(uint z); void init(); void main() { init();//初始化子程序 while(1) { if(aa==20) { aa=0; temp++; if(temp==99999) { temp=0; } wang=temp/10000; qian=(temp-wang*10000)/1000; bai=(temp-wang*10000-qian*1000)/100; shi=(temp-wang*10000-qian*1000-bai*100)/10; ge=temp%10; } display(wang,qian, bai,shi,ge); } } void delay(uint z) { uint x,y; for(x=z;x>0;x--) for(y=110;y>0;y--); } void display(uint wang,uint qian,uint bai,uint shi,uint ge) { dula=1; P0=table[wang]; dula=0; P0=0xff; wela=1; P0=0xfe; wela=0; delay(1); dula=1; P0=table[qian]; dula=0; P0=0xff; wela=1; P0=0xfd; wela=0; delay(1); dula=1; P0=table[bai]; dula=0; P0=0xff; wela=1; P0=0xfb; wela=0; delay(1); dula=1; P0=table[shi]; dula=0; P0=0xff; wela=1; P0=0xf7; wela=0; delay(1); dula=1; P0=table[ge]; dula=0; P0=0xff; wela=1; P0=0xef; wela=0; delay(1); } void init() { wela=0; dula=0; temp=0; TMOD=0x01; TH0=(65536-50000)/256; TL0=(65536-50000)%256; EA=1; ET0=1; TR0=1; } void timer0() interrupt 1 { TH0=(65536-50000)/256; TL0=(65536-50000)%256; aa++; } include<reg52.h> #define uint unsigned int #define uchar unsigned char uint temp,aa,wang,qian,bai,shi,ge; sbit dula=P2^6; sbit wela=P2^7; uchar code table[]={ 0x3f,0x06,0x5b,0x4f, 0x66,0x6d,0x7d,0x07, 0x7f,0x6f,0x77,0x7c, 0x39,0x5e,0x79,0x71}; void display( uint wang,uint qian,uint bai,uint shi,uint ge); void delay(uint z); void init(); void main() { init();//初始化子程序 while(1) { if(aa==20) { aa=0; temp++; if(temp==99999) { temp=0; } wang=temp/10000; qian=(temp-wang*10000)/1000; bai=(temp-wang*10000-qian*1000)/100; shi=(temp-wang*10000-qian*1000-bai*100)/10; ge=temp%10; } display(wang,qian, bai,shi,ge); } } void delay(uint z) { uint x,y; for(x=z;x>0;x--) for(y=110;y>0;y--); } void display(uint wang,uint qian,uint bai,uint shi,uint ge) { dula=1; P0=table[wang]; dula=0; P0=0xff; wela=1; P0=0xfe; wela=0; delay(1); dula=1; P0=table[qian]; dula=0; P0=0xff; wela=1; P0=0xfd; wela=0; delay(1); dula=1; P0=table[bai]; dula=0; P0=0xff; wela=1; P0=0xfb; wela=0; delay(1); dula=1; P0=table[shi]; dula=0; P0=0xff; wela=1; P0=0xf7; wela=0; delay(1); dula=1; P0=table[ge]; dula=0; P0=0xff; wela=1; P0=0xef; wela=0; delay(1); } void init() { wela=0; dula=0; temp=0; TMOD=0x01; TH0=(65536-50000)/256; TL0=(65536-50000)%256; EA=1; ET0=1; TR0=1; } void timer0() interrupt 1 { TH0=(65536-50000)/256; TL0=(65536-50000)%256; aa++; } include<reg52.h> #define uint unsigned int #define uchar unsigned char uint temp,aa,wang,qian,bai,shi,ge; sbit dula=P2^6; sbit wela=P2^7; uchar code table[]={ 0x3f,0x06,0x5b,0x4f, 0x66,0x6d,0x7d,0x07, 0x7f,0x6f,0x77,0x7c, 0x39,0x5e,0x79,0x71}; void display( uint wang,uint qian,uint bai,uint shi,uint ge); void delay(uint z); void init(); void main() { init();//初始化子程序 while(1) { if(aa==20) { aa=0; temp++; if(temp==99999) { temp=0; } wang=temp/10000; qian=(temp-wang*10000)/1000; bai=(temp-wang*10000-qian*1000)/100; shi=(temp-wang*10000-qian*1000-bai*100)/10; ge=temp%10; } display(wang,qian, bai,shi,ge); } } void delay(uint z) { uint x,y; for(x=z;x>0;x--) for(y=110;y>0;y--); } void display(uint wang,uint qian,uint bai,uint shi,uint ge) { dula=1; P0=table[wang]; dula=0; P0=0xff; wela=1; P0=0xfe; wela=0; delay(1); dula=1; P0=table[qian]; dula=0; P0=0xff; wela=1; P0=0xfd; wela=0; delay(1); dula=1; P0=table[bai]; dula=0; P0=0xff; wela=1; P0=0xfb; wela=0; delay(1); dula=1; P0=table[shi]; dula=0; P0=0xff; wela=1; P0=0xf7; wela=0; delay(1); dula=1; P0=table[ge]; dula=0; P0=0xff; wela=1; P0=0xef; wela=0; delay(1); } void init() { wela=0; dula=0; temp=0; TMOD=0x01; TH0=(65536-50000)/256; TL0=(65536-50000)%256; EA=1; ET0=1; TR0=1; } void timer0() interrupt 1 { TH0=(65536-50000)/256; TL0=(65536-50000)%256; aa++; }
标签： 矩阵式键盘
上传时间： 2021-12-18
上传用户：2590813506
