移动通信网络由于带宽和技术的限制,远远不能满足人们不断高涨的无线上网需求。Wi-Fi作为无线接入技术MLAN的主流标准口益成熟,它能够随时随地高速连接到Internet,极大地满足了用户对无线上网需求,受到消费者的青睐。因而越来越多的移动终端都集成了Wi-Fi功能,Wi-Fi和蓝牙样成为移动终端的标配。随之而来的是wi-Fi和蓝牙都工作在2.4CHZz ISM频段而引发的互相 扰问题,导致数据吞吐量下降,语音质量恶化失真,极端状况下甚至导致链路断开而不能正常工作。因此,必须寻求有效的措施和方法,实现两种技术在近距离的和谐共存,这已成为非常迫切的技术需要,也成为人们研究的一个热点和难点。近距离WiFi和蓝牙互相1扰的问题,目前已经形成了非常多的有效解决机制,包括基于Wi-Fi的PTA(Packet Traffic Arbitration)、AWMA(Alternating Wireless Medium Access)和DSE(Deterministic Spectral Excision),其中PTA和AWMA机制在Wi-Fi側MAC层实现,通过协调Wi-Fi和蓝牙的帧发射时间来避免相互干扰:而DSE是在Wi-Fi侧物理层PHY实现,通过一个可编程带阻滤波器(Notch Filter)来阻止来白蓝牙的窄带干扰。还有基于蓝牙侧的AFH(ADAPTIVE Frequency Hopping),它通过跳频,自动避开被干扰的频点,从而大大提高了蓝牙传输性能。
上传时间: 2022-06-20
上传用户:zhanglei193
INTRODUCTION In the past, adding speech recording and playback capability to a product meant using a digital signal processor or a specialized audio chip. Now, using a simplified ADAPTIVE Differential Pulse Code Modulation(ADPCM) algorithm, these audio capabilities can be added to any PICmicro device. This application note will cover the ADPCM compression and decompression algorithms, performance comparison of all PICmicro devices, and an application using a PIC16C72 micro-controller.DEFINITION OF TERMS step size -value of the step used for quantization of ana-log signals and inverse quantization of a number of steps.quantization -the digital form of an analog input signal is represented by a finite number of steps.ADAPTIVE quantization -the step size of a quantizer is dramatically changed with time in order to adapt to a changing input signal.inverse quantizer -a finite number of steps is converted into a digital representation of an analog signal.
上传时间: 2022-06-20
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German universities and scientists have repeatedly set the intermational standard in drive technology. Identification and active compensation of natural frequencies in oscillatory mechanics, status controls with monitoring structures incorporating acceleration sensors, ADAPTIVE compensation of measurement system deficiencies, self-adjusting detent torque compensation… everything invented with only a single aim in mind: to continue improv-ing the motion control, dynamics, precision and processing speed of your machines. For the industrial applicabability of this technology scientific publications in proceedings and laboratory test rigs are not enough. These features consequenty need to be converted into cost-efficient and easily manageable products. That 's exactly what we have done.So in future, if you should need more than today ' smarket can offer you, now everything isgoing to be alright. With our new high-performance ServoOne drive series you will experi-ence
标签: servoone
上传时间: 2022-06-24
上传用户:kingwide
STM32F407VET6数据手册Core: ARM 32-bit Cortex™-M4 CPU with FPU,ADAPTIVE real-time accelerator (ARTAccelerator™) allowing 0-wait state executionfrom Flash memory, frequency up to 168 MHz,memory protection unit, 210 DMIPS/1.25 DMIPS/MHz (Dhrystone 2.1), and DSPinstructions
标签: stm32f407vet6 数据手册
上传时间: 2022-07-25
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