Radio receiver

DETAILED DESCRIPTION Therefore, this invention was created in view of the above-mentioned facts, and an object thereof is to provide a circuit constructing technique for a radio receiver which keeps intact the advantages of the direct conversion system in that it can avoid image disturbance, and further which can utilize various LSI circuits for IF amplification and demodulation which have been developed for the heterodyne system and are easily available in the market.
Accordingly, in accordance with this invention, a radio receiver which has simple circuit construction and also is easy in demodulation can be provided.
In order to achieve the object described above and still others, the received input signal is first direct-frequency-converted to drop it to two axial (I-axis and Q-axis) base-band components of in-phase and orthogonal phase.
At this stage, requisite selectivity is secured.
Then, these base-band components are re-modulated and thereafter composed to provide a single IF signal.
This IF signal is amplified by a required amplification degree.
Other objects, features and advantages of the invention will become apparent from a reading of the specification, when taken in conjunction with the drawings.