使用锁相环MB1504，MC34063，超外差
标签： 解调电路
上传时间： 2016-11-28
上传用户：q287671984
单片机 ：AT89S52 或 STC89C52RC 典型传感器：AM2301 功能 ：串口发送温湿度数据 波特率 9600 晶振 ：12M (用户系统时钟如不是12M 请更改相关宏定义及注释的延时时间) 编译环境: Keil 4
上传时间： 2018-07-27
上传用户：gmc832002
BK全系列的无线麦克风发射/接收芯片，采用24Bit/48KHz的高性能音频专用的Δ-Σ的 A/D 和D/A 处理，采用1/4πDQPSK 数字调制/解调方式，全数字无线传输，有别于传统的FM 调制/解调方式，音频传输过程中无需进行压缩/扩展处理，也无需进行预加重/去加重处理， 保留声音的原汁原味，所以声音的频响，瞬态，线性等指标都很好，非常接近有线麦克风的 音质，也就是说：同样的咪芯，采用有线的连接方式，能达到的音质效果，采用BK芯片，无 线的效果和有线的效果可以非常地接近。
上传时间： 2019-11-11
上传用户：picq
Optical communication technology has been extensively developed over the last 50 years, since the proposed idea by Kao and Hockham [1]. However, only during the last 15 years have the concepts of communication foundation, that is, the modulation and demodulation techniques, been applied. This is pos- sible due to processing signals using real and imaginary components in the baseband in the digital domain. The baseband signals can be recovered from the optical passband region using polarization and phase diversity tech- niques, as well as technology that was developed in the mid-1980s.
标签： Transmission Processing Digital Optical
上传时间： 2020-05-27
上传用户：shancjb
Multi-carrier modulation‚ Orthogonal Frequency Division Multi- plexing (OFDM) particularly‚ has been successfully applied to a wide variety of digital communications applications over the past several years. Although OFDM has been chosen as the physical layer standard for a diversity of important systems‚ the theory‚ algorithms‚ and implementation techniques remain subjects of current interest. This is clear from the high volume of papers appearing in technical journals and conferences.
标签： COMMUNICATIONS MULTI-CARRIER DIGITAL
上传时间： 2020-05-31
上传用户：shancjb
All wireless communication standards, existing and under development, adopt or consider adopting orthogonal frequency-division multiplexing (OFDM) as the modulation technique. It is clear that OFDM has become the definitive modulation scheme in current and future wireless communication systems.
标签： Baseband Receiver Design OFDM
上传时间： 2020-05-31
上传用户：shancjb
Before I can present design concepts or tactical wireless communications and network challenges, I feel the need to mention the challenges of writing for a field where some information is not available for public domain and cannot be included in this book’s context. Another challenge is the use of military jargon and the extensive number of abbreviations (and abbreviations of abbreviations!) in the field. Engineering books are naturally dry, and I have attempted to make it light by presenting the concepts in layman’s terms before diving into the technical details. I am structuring this book in such a way as to make it useful for a specialized graduate course in tactical communications and networking, or as a reference book in the field.
标签： Communications Tactical Networks Wireless and
上传时间： 2020-06-01
上传用户：shancjb
T his book covers basic communications theory and practical imple- mentation of transmitters and receivers. In so doing, I focus on dig- ital modulation, demodulation methods, probabilities, detection of digital signals, and spread spectrum system design and analysis. This book was written for those who want a good understanding of the basic prin- ciples of digital wireless communication systems, including spread spec- trum techniques. This book also provides a good intuitive and practical approach to digital communications. Therefore it is a valuable resource for anyoneinvolvedinwirelesscommunicationsandtransceiverdesignfordig- ital communications. The reader will gain a broad understanding of basic communication principles for transceiver design, digital communications, and spread spectrum, along with examples of many types of commercial and military data link systems.
标签： Transceiver System Design
上传时间： 2020-06-01
上传用户：shancjb
This is a practical book, to be sure, but it is also a book about hope and posi- tive change. I am quite sincere. The delivery of electricity is deeply rooted in the principle of universal access; when clean, reliable energy is available it contributes to poverty alleviation, improved social conditions, and enhanced economic development. In the developed world, we know this to be true. The digital fabric of our lives is a testimony to the importance of energy security. Across the globe, we have seen the vital contributions that electrification has brought to the development of economies and an enhanced quality of life. Nonetheless, this supreme engineering achievement has languished, and we are deeply challenged.
标签： Strategies Analytics Data Big
上传时间： 2020-06-07
上传用户：shancjb
Introduction to Radio Frequency Identification (RFID): RFID is a wireless modulation and demodulation technique for automatic identification of objects, tracking goods, smart logistics, and access con- trol. RFID is a contactless, usually short‐distance transmission and reception technique for unique ID data transfer from a tagged object to an interrogator (reader). The generic configuration of an RFID system comprises (i) an ID data‐carrying tag, (ii) a reader, (iii) a middleware, and (iv) an enterprise application.
标签： Chipless_Radio_Frequency_Identifi cation
上传时间： 2020-06-08
上传用户：shancjb
