Patent attributes
A non-coherent synchronous direct-conversion receiving apparatus is provided. The apparatus includes a RF receiving unit, an I/Q ADC unit, and a digital signal processing unit for analyzing the digital signal received from the I/Q ADC unit to adjust a bandwidth of a variable receiving filtering unit according to the analyzing result, compensating a frequency offset to be correspondent with a symbol transmitting rate by extracting frequency offset information from the digital signal, compensating a frequency offset using the analyzing result, and applying a voltage corresponding to a sum of compensating values to the RF receiving unit. Therefore, the apparatus can compensate a frequency offset regardless of the magnitude of a frequency offset and performs a stable AFC operation through varying the bandwidth of a receiving filter by estimating the frequency offset with only data information, and adjusting a reference frequency twice through an interface signal.