This is the fifth in a series of computer science lessons about wireless communication and digital signal processing. In these lessons you’ll learn about the nature of electromagnetic radiation, digital modulation and multiplexing techniques, and how to get the best out of mobile communication systems such as LTE, 5G and WiFi. In this lesson, you will learn about the modulation of digital data, which is known as shift keying. Four types of keying can be used to transmit digital data via radio; on-off keying, amplitude shift keying, frequency shift keying and phase shift keying, also known as binary phase shift keying (BPSK). With BPSK in particular, you will learn that a stream of binary digits are first line coded to generate a polar non return to zero (NRZ) baseband signal. The stream of symbols produced is then multiplied by a continuous wave carrier to create the modulated signal. Chapters: 00:00 Introduction 00:25 Digital data 01:10 On off keying 01:55 Amplitude shift keying 04:52 Frequency shift keying 05:39 Binary Phase shift keying