Patent ID: 9356810
Filing Date: 2016-05-31
CPC Classification: H04B,H04L

Claim Text:
1. A semiconductor integrated circuit comprising: a first wireless access system reception unit comprising a first analog reception unit and a first digital reception unit; a voltage-controlled oscillator; a phase locked loop; a digital interface, wherein the first analog reception unit comprises a first reception mixer for down-converting an RF reception signal into a first analog reception signal and a first analog-digital converter for converting the first analog reception signal into a first digital reception signal, and wherein the first wireless access system reception unit, the voltage-controlled oscillator, and the phase locked loop enable switching from a reception operation for a first RF reception signal of a first system to a reception operation for a second RF reception signal of a second system; and a second wireless access system reception unit comprising a second analog reception unit and a second digital reception unit, wherein the second analog reception unit comprises a second reception mixer for down-converting an RF reception signal into a second analog reception signal and a second analog-digital converter for converting the second analog reception signal into a second digital reception signal, wherein the second digital reception unit comprises a second digital filter including an input terminal to which the second digital reception signal is supplied, wherein a second digital filter reception output signal outputted from an output terminal of the second digital filter in the second digital reception unit can be outputted to the outside of the semiconductor integrated circuit through the digital interface, wherein the voltage-controlled oscillator generates an oscillation output signal as a base for the first reception local signal supplied to the first reception mixer, and the phase locked loop locks a frequency of the oscillation output signal generated from the voltage-controlled oscillator to a desired frequency of the first system, wherein the voltage-controlled oscillator generates an oscillation output signal as a base for a second reception local signal supplied to the second reception mixer, and the phase locked loop locks a frequency of the oscillation output signal generated from the voltage-controlled oscillator to a desired frequency of the second system, wherein the first wireless access system reception unit, the voltage-controlled oscillator, and the phase locked loop can perform the reception operation for the first RF reception signal of the first system, wherein the second wireless access system reception unit, the voltage-controlled oscillator, and the phase locked loop can perform the reception operation for the second RF reception signal of the second system, wherein the first wireless access system reception unit, the second wireless access system reception unit, the voltage-controlled oscillator, and the phase locked loop enable switching from the reception operation for the first RF reception signal of the first system to the reception operation for the second RF reception signal of the second system, wherein in the switching, as for the reception operation for the first RF reception signal of the first system, the end transition operation of the first digital reception unit is performed subsequent to the end transition operation of the first analog reception unit, wherein in the switching, for the reception operation for the second RF reception signal of the second system, a start transition operation of the second analog reception unit and a start transition operation of the second digital reception unit are performed, and wherein in a period of the end transition operation of the first digital reception unit in the switching, the phase locked loop starts a lock operation so as to match the frequency of the oscillation output signal generated from the voltage-controlled oscillator to the desired frequency of the second system.