What is the difference between 1.5Gbps and 1.5GHz?

Answer 1

1.5 Gbps means "1.5 billion bits per second", typically referring to a transfer rate for data. 1.5 GHz means "1.5 billion Hertz" where Hertz is a unit of frequency in cycles per second. Frequency, then, is a more general term than bits per second and is applied in many other areas besides data transmission. Transferring data at 1.5 Gbps will typically not mean sending a signal with a frequency of 1.5 GHz. Data is sent in "symbols", where a symbol is a specific state of frequency, amplitude, and phase. By using different combinations of those parameters, a data rate of 1.5 Gbps may transmitted with a signal that possesses a fundamental frequency considerably more or less than 1.5 GHz.