Wireless Transceiver: A transceiver is a combination of a transmitter and receiver used for wireless communication.
Radio: The radio is the primary component responsible for:
Modulation: Encoding data onto a carrier wave.
Demodulation: Extracting data from a received signal.
Transmission/Reception: Handling the actual sending and receiving of modulated signals over the air.
References
Transceiver: https://en.wikipedia.org/wiki/Transceiver

Free Space Path Loss (FSPL): Describes how a radio signal weakens as it travels through open space, even without obstacles. It's caused by the signal spreading out, resulting in decreased power density at the receiver.
Calculation: FSPL depends on distance and frequency.
References
Free Space Path Loss: https://en.wikipedia.org/wiki/Free-space_path_loss

Key Modulation Differences:
ASK (Amplitude Shift Keying): Digital data is represented by changes in the amplitude (strength) of a carrier wave.
FSK (Frequency Shift Keying): Digital data is represented by changes in the frequency of a carrier wave.
References
ASK: https://en.wikipedia.org/wiki/Amplitude-shift_keying
FSK: https://en.wikipedia.org/wiki/Frequency-shift_keying