SVG--key-technologies

使用stm32开发板做的pwm输出控制buck电路，反馈使用PID算法，实现闭环控制(The use of STM32 development board to do PWM output control buck circuit, feedback using PID algorithm to achieve closed-loop control)

：LTE(Long Term Evolution，长期演进)系统中的小区初始搜索过程通过分别检测主同步信号(Primary Synchronization Signal，PSS)和辅同步信号(Secondary Synchronization Signal，SSS)来完成，搜 索结果包括小区组ID、符号定时、频偏估计、组内小区ID以及帧定时[1]。然而，若接收信号   1IDN  2IDN 中存在整数倍频偏，则由于时域的相位旋转，主同步信号将很难用传统的相关算法检测到。提出一种主同步信号与整数倍频偏联合检测的方法，即使存在整数倍频偏，也能得到正确的符号定时。辅同步信号采用的是非相干的差分相关检测[2]，仿真表明，与传统的匹配滤波算法相比，可以有效的对抗信道时延扩展和载波频偏，适用于高速场景下时分双工(Time Division Duplex，TDD)LTE系统的同步。(In LTE systems, the initial cell search process is completed by detecting the primary synchroniza-tion signal and the secondary synchronization signal. The searching results include cell ID group, symbol timing, frequency offset estimation, intra group cell ID and frame timing[1]. However, if integer frequency offset presents in the received signal, due to time-domain phase rotation, the primary synchronization signal will be difficult to detected using the conventional correlation algorithm. A new joint detection method for integer frequency offset and primary synchronization signal is proposed, which can get the correct symbol timing even if the presence of integer frequency offset. Secondary synchronization signal is processed using the differential non-coherent correlation detection method[2]. Simulations show that compared with the tradi-tional matched filtering algorithms, it can effectively combat the channel delay spread and carrier frequency offset and especially suitable for )

光伏逆变器的双闭环控制仿真原理图 dc-dc采用mppt跟中(The double closed loop control simulation diagram of photovoltaic inverter)

AVR-MEGA8单片机中使用AD转换的一个例子，原本是用于锂电池充电器中实时检测电量的。程序没有采用中断方式，而是软件调用AD转换函数。(AVR-MEGA8 Singlechip AD converter used in an example of the original lithium battery charger for real-time detection of electricity. Procedures did not interrupt, but the software AD conversion function call.)

AVR单片机ATMEGA系列SPI接口的驱动程序。(AVR Singlechip ATMEGA series SPI interface driver.)

this is puzl game first , load a picture, and chose picture

LCD初始化代码，能够点亮SSD2119 driver IC液晶屏(init LCD)

好的声文同步程序，值得学习，适合于初学者，给大家共同分享(Good sound text synchronization process, it is worth learning, suitable for beginners, for everyone to share)

这是一个基于C51的软件模拟串口程序，希望对大家有用。(This is a C51-based simulation software serial procedures in the hope that useful.)

该程序为数码管静态显示程序。 每按一次 独立按键 中的 T0，数码管的值便会加一(The procedure for the digital static display program. Each time you press the button in the Independent, the value of the digital tube will add a T0)