A global navigation satellite system receiver (100A, 100B) comprising: a radio frequency front end including: at least one radio frequency input; a first variable gain amplifier configured to adjust a first gain of a first frequency range of a first analog global navigation satellite system signal received from the at least one radio frequency input by a first amount; and a second variable gain amplifier configured to adjust a second gain of a second frequency range of a second analog global navigation satellite system signal received from the at least one radio frequency input by a second amount; and characterized in that the global navigation satellite system receiver (100A, 100B) comprises: a digital processing functionality configured to: compare the first amount of adjustment of the first gain of the first frequency range with the second amount of adjustment of the second gain of the second frequency range; and detect a first interference signal present in the first frequency range or the second frequency range when the first amount of adjustment of the first gain of the first frequency range differs from the second amount of adjustment of the second gain of the second frequency range by more than a first threshold amount. a radio frequency front end including: at least one radio frequency input; a first variable gain amplifier configured to adjust a first gain of a first frequency range of a first analog global navigation satellite system signal received from the at least one radio frequency input by a first amount; and a second variable gain amplifier configured to adjust a second gain of a second frequency range of a second analog global navigation satellite system signal received from the at least one radio frequency input by a second amount; and at least one radio frequency input; a first variable gain amplifier configured to adjust a first gain of a first frequency range of a first analog global navigation satellite system signal received from the at least one radio frequency input by a first amount; and a second variable gain amplifier configured to adjust a second gain of a second frequency range of a second analog global navigation satellite system signal received from the at least one radio frequency input by a second amount; and a digital processing functionality configured to: compare the first amount of adjustment of the first gain of the first frequency range with the second amount of adjustment of the second gain of the second frequency range; and detect a first interference signal present in the first frequency range or the second frequency range when the first amount of adjustment of the first gain of the first frequency range differs from the second amount of adjustment of the second gain of the second frequency range by more than a first threshold amount. compare the first amount of adjustment of the first gain of the first frequency range with the second amount of adjustment of the second gain of the second frequency range; and detect a first interference signal present in the first frequency range or the second frequency range when the first amount of adjustment of the first gain of the first frequency range differs from the second amount of adjustment of the second gain of the second frequency range by more than a first threshold amount.