What is a direct conversion receiver?

Direct conversion receiver (DCR) is a radio receiver that reproduces the original information signal that could be a sound, video or data, from the original source or radio transmitter, air signal sources. It does not require the transfer of the received signal to the middle signal. The direct conversion receiver has fewer parts than about half of the other types of radio receivers. Inside the direct conversion receiver is a radio source known as a local oscillator that is tuned to the same frequency as the air signal. It is then converted into electrical signals to the same frequency in cycles per second as a transmitted signal of the radio receiver antenna. For example, a radio signal at 500 Kilohertz (KHZ), or 500,000 cycles per second, the avyster will travel through the air as an air signal, reach the receiver antenna, and become electrical signals at the same frequency or 500,000 cycles per second. The levels are usually very low when the receiver input. It requires sensitive circuits inside the DCR,that amplifies the received signal.

Em wave at the receiver input was modified in a certain form to carry the original signal or information. When the average wave level is modified, the amplitude modulation (AM) is called. When the immediate frequency of EM is in proportion to the source of information, it is referred to as frequency modulation (FM). These are two common modulations or methods to include information in EM wool or radio frequency carrier (RF).

Once the RF carrier is on the input of a direct conversion and DCR are tuned to it, modulation can be extracted by the principle known as mixing and detection. In the mixing process, the signal from the transmitter and signal from the local source, known as the local oscillator, inside the DCR is used. Both signals will be brought to the blender detector and the result is information from the transmitter.

Direct conversion receiver is also referred to as homodyne because it usesone frequency. It is also known as synchrodyne because it uses a sychronized RF source or almost the same phase and frequency as a received signal. Other types of receivers require additional frequency or medium frequency (IF) for further processing of the received signal. DCR does not need no, so it is also called a receiver with zero if.