Patent ID: 8918060

Claim:
A method of self testing a transmission chain in a mobile phone radio device, the method comprising: producing, by an RF transmit circuit portion of the mobile phone radio device, a modulated baseband signal within a preselected channel within a preselected receive frequency band; amplifying the modulated baseband signal; providing the amplified modulated baseband signal to a first node of an antenna switch module; receiving a first attenuated signal on a second node of the antenna switch module via a first leakage signal path between the first node and the second node, the first node and the second node not being on a same electrical signal path, the first attenuated signal comprising an attenuated version of the amplified modulated baseband signal; filtering the first attenuated signal by a first bandpass filter adapted to pass the preselected receive frequency band, the first bandpass filter outputting a loopback signal, the loopback signal being a first bandpass filtered version of the first attenuated signal; receiving the loopback signal by a first Low Noise Amplifier (LNA) in a first RF receive circuit portion of the mobile phone radio device, the first LNA receives an attenuated loopback signal via a second leakage signal path that is between the first bandpass filter and the first LNA, the first LNA is not in a same receive signal oath as the first bandpass filter, the first LNA is adjacent to a second LNA wherein the second LNA is in a same direct receive signal path past the first bandpass filter, the first leakage signal path being in series with the second leakage signal path; producing, by the first RF receive circuit portion, a received digital representation of the baseband signal from the attenuated loopback signal; calculating by a Digital Base Band (DBB) block a transmit quantification measurement of the RF transmit circuit portion using the received digital representation of the baseband signal.