Signal processing device, signal processing method, recording medium, and mobile body

A signal processing method comprising:

• estimating a first transmission path characteristic of a transmission signal using, out of a vertical signal and a horizontal signal, the vertical signal, the transmission signal being transmitted from a transmission device in form of one of vertical polarization and horizontal polarization, the vertical signal and the horizontal signal resulting from a vertical polarization antenna and a horizontal polarization antenna receiving the transmission signal;
• estimating a second transmission path characteristic of the transmission signal using the horizontal signal;
• calculating a first weight for the vertical signal and a second weight for the horizontal signal, using the first transmission path characteristic and the second transmission path characteristic;
• applying weighted summation to the vertical signal and the horizontal signal using the first weight and the second weight;
• performing synchronization processing on each of the vertical signal and the horizontal signal;
• designating a handover candidate signal;
• determining, according to the designating of the handover candidate signal, whether a reception signal or the handover candidate signal satisfies a predetermined condition, the reception signal resulting from being received by an antenna for polarization different from polarization of the transmission signal, out of the vertical polarization antenna and the horizontal polarization antenna;
• outputting a handover execution signal when the reception signal or the handover candidate signal is determined to satisfy the predetermined condition;
• and
• switching, according to the outputting of the handover execution signal, a signal to be processed from the transmission signal to the handover candidate signal in the synchronization processing, estimating the first transmission path characteristic, estimating the second transmission path characteristic, calculating the first weight, calculating the second weight, and applying the weighted summation,
• wherein the first transmission path characteristic is a characteristic of a transmission path through which the transmission signal is transmitted from the transmission device to the vertical polarization antenna,
• the second transmission path characteristic is a characteristic of a transmission path through which the transmission signal is transmitted from the transmission device to the horizontal polarization antenna,
• the first transmission path characteristic indicates a proportion of a signal included in the vertical signal within the transmission signal, and
• the second transmission path characteristic indicates a proportion of a signal included in the horizontal signal within the transmission signal.

A non-transitory computer-readable recording medium having a program recorded thereon, the program causing a computer to execute:

• estimating a first transmission path characteristic of a transmission signal using, out of a vertical signal and a horizontal signal, the vertical signal, the transmission signal being transmitted from a transmission device in form of one of vertical polarization and horizontal polarization, the vertical signal and the horizontal signal resulting from a vertical polarization antenna and a horizontal polarization antenna receiving the transmission signal;
• estimating a second transmission path characteristic of the transmission signal using the horizontal signal;
• calculating a first weight for the vertical signal and a second weight for the horizontal signal, using the first transmission path characteristic and the second transmission path characteristic;
• applying weighted summation to the vertical signal and the horizontal signal using the first weight and the second weight;
• performing synchronization processing on each of the vertical signal and the horizontal signal;
• designating a handover candidate signal;
• determining, according to the designating of the handover candidate signal, whether a reception signal or the handover candidate signal satisfies a predetermined condition, the reception signal resulting from being received by an antenna for polarization different from polarization of the transmission signal, out of the vertical polarization antenna and the horizontal polarization antenna;
• outputting a handover execution signal when the reception signal or the handover candidate signal is determined to satisfy the predetermined condition;
• and
• switching, according to the outputting of the handover execution signal, a signal to be processed from the transmission signal to the handover candidate signal in the synchronization processing, estimating the first transmission path characteristic, estimating the second transmission path characteristic, calculating the first weight, calculating the second weight, and applying the weighted summation,
• wherein the first transmission path characteristic is a characteristic of a transmission path through which the transmission signal is transmitted from the transmission device to the vertical polarization antenna,
• the second transmission path characteristic is a characteristic of a transmission path through which the transmission signal is transmitted from the transmission device to the horizontal polarization antenna,
• the first transmission path characteristic indicates a proportion of a signal included in the vertical signal within the transmission signal, and
• the second transmission path characteristic indicates a proportion of a signal included in the horizontal signal within the transmission signal.

A mobile body comprising:

• a signal processing device;
• a vertical polarization antenna;
• and
• a horizontal polarization antenna,
• wherein the signal processing device includes:
• a first transmission path estimator that estimates a first transmission path characteristic of a transmission signal using, out of a vertical signal and a horizontal signal, the vertical signal, the transmission signal being transmitted from a transmission device in form of one of vertical polarization and horizontal polarization, the vertical signal and the horizontal signal resulting from the vertical polarization antenna and the horizontal polarization antenna receiving the transmission signal;
• a second transmission path estimator that estimates a second transmission path characteristic of the transmission signal using the horizontal signal;
• a weight calculator that calculates a first weight for the vertical signal and a second weight for the horizontal signal, using the first transmission path characteristic and the second transmission path characteristic;
• a weighting applier that applies weighted summation to the vertical signal and the horizontal signal using the first weight and the second weight;
• a synchronization processor that performs synchronization processing on each of the vertical signal and the horizontal signal;
• and
• a handover controller that designates a handover candidate signal,
• the first transmission path characteristic is a characteristic of a transmission path through which the transmission signal is transmitted from the transmission device to the vertical polarization antenna,
• the second transmission path characteristic is a characteristic of a transmission path through which the transmission signal is transmitted from the transmission device to the horizontal polarization antenna,
• the first transmission path characteristic indicates a proportion of a signal included in the vertical signal within the transmission signal,
• the second transmission path characteristic indicates a proportion of a signal included in the horizontal signal within the transmission signal,
• when the handover candidate signal is designated, the synchronization processor determines whether a reception signal or the handover candidate signal satisfies a predetermined condition, the reception signal resulting from being received by an antenna for polarization different from polarization of the transmission signal, out of the vertical polarization antenna and the horizontal polarization antenna,
• the handover controller outputs a handover execution signal when the synchronization processor determines that the reception signal or the handover candidate signal satisfies the predetermined condition, and
• when the handover execution signal is obtained, the synchronization processor, the first transmission path estimator, the second transmission path estimator, the weight calculator, and the weighting applier switch a signal to be processed from the transmission signal to the handover candidate signal.