Receivers: From Spark to 16-QAM
Course Description
In the earliest days of wireless communication, receivers were extremely primitive. Spark-gap transmitters produced high-voltage sparks to generate radio waves, which could then be detected by coherers. Coherers were simple devices containing metal filings that became conductive when exposed to radio waves. These devices had to be manually reset after each detection, making continuous operation difficult. They offered very low sensitivity and poor selectivity, meaning they could not effectively distinguish between closely spaced frequencies. Additionally, these early receivers were highly vulnerable to atmospheric noise and interference from other transmissions. Despite these limitations, spark and coherer receivers demonstrated the feasibility of wireless communication, forming the foundation for all subsequent advancements in receiver design.
What you'll learn in this course?
Understand the evolution of receivers from early spark-gap designs to modern digital implementations.
Explain the principles of amplitude, frequency, and phase modulation reception.
Describe the operation of superheterodyne and software-defined receivers.
Analyze the role of mixers, filters, and demodulators in receiver chains.
Compare digital modulation schemes, including PSK, QAM, and OFDM.
Apply design considerations for low-noise and high-efficiency receiver systems.
Prerequisites
Basic understanding of AC signals, frequency, and electronic circuits
Familiarity with communication-system terminology is helpful