Diagnostic method for a radio broadcast receiving system and the radio broadcast receiving system

A diagnostic method for a radio broadcast receiving system of a motor vehicle, the diagnostic method comprising:

• performing a reference measurement by
• switching off a first receiver in a first transmission/reception path of the radio broadcast receiving system, wherein the first transmission/reception path comprises the first receiver with a first local oscillator and a first antenna connected to the first receiver for signal transmission;
• receiving, via a second antenna in a second transmission/reception path of the radio broadcast receiving system, a surroundings signal of a predetermined test frequency, wherein the second transmission/reception path comprises the second receiver and the second antenna connected to a second receiver for signal transmission, and wherein the first and second antennas are couplable to each other to transmit signals;
• passing, by the second receiver to a controller of the radio broadcast receiving system, the received surroundings signal;
• and
• storing, by the controller, the received surroundings signal;
• and
• performing a diagnosis of the radio broadcast receiving system by
• generating, by the first local oscillator, a test signal with the predetermined test frequency;
• transmitting, via the first antenna, the test signal;
• receiving, via the second antenna and the second receiver, the transmitted test signal;
• passing, by the second receiver to the controller, the received test signal;
• and
• evaluating, by the controller based on the received test signal and the stored received surroundings signal, functionality of the second antenna.

A radio broadcast receiving system for a motor vehicle, the radio broadcast receiving system comprising:

• a first transmission/reception path comprising a first receiver with a first local oscillator and a first antenna connected to the first receiver for signal transmission;
• a second transmission/reception path with a second receiver and a second antenna connected to the second receiver for signal transmission, wherein the first and second antennas are couplable to each other to transmit signals;
• and
• a controller configured to control the first and second transmission/reception paths,
• wherein in a reference measurement
• the controller is configured to switch off the first receiver;
• the second antenna is configured to receive a surroundings signal of a predetermined test frequency;
• the second receiver is configured to pass the received surroundings signal to the controller;
• and
• the controller is configured to store the received surroundings signal;
• and
• wherein in a diagnosis of the radio broadcast receiving system
• the first local oscillator is configured to generate a test signal with the predetermined test frequency;
• the first antenna is configured to transmit the test signal;
• the second antenna and the second receiver are configured to receive the transmitted test signal;
• passing, the second receiver is configured to pass the received test signal to the controller;
• and
• the controller is configured to evaluate, based on the received test signal and the stored received surroundings signal, functionality of the second antenna.

A motor vehicle comprising:

• at least one window;
• and
• a radio broadcast receiving system comprising
• a first transmission/reception path comprising a first receiver with a first local oscillator and a first antenna connected to the first receiver for signal transmission;
• a second transmission/reception path with a second receiver and a second antenna connected to the second receiver for signal transmission, wherein the first and second antennas are couplable to each other to transmit signals;
• and
• a controller configured to control the first and second transmission/reception paths,
• wherein in a reference measurement
• the controller is configured to switch off the first receiver;
• the second antenna is configured to receive a surroundings signal of a predetermined test frequency;
• the second receiver is configured to pass the received surroundings signal to the controller;
• and
• the controller is configured to store the received surroundings signal;
• and
• wherein in a diagnosis of the radio broadcast receiving system
• the first local oscillator is configured to generate a test signal with the predetermined test frequency;
• the first antenna is configured to transmit the test signal;
• the second antenna and the second receiver are configured to receive the transmitted test signal;
• passing, the second receiver is configured to pass the received test signal to the controller;
• and
• the controller is configured to evaluate, based on the received test signal and the stored received surroundings signal, functionality of the second antenna,
• wherein the first and second antennas are window antennas, and
• wherein the first and second antennas are installed on a same one of the at least one window or the first and second antennas are installed on different ones of the at least one window.