Patent attributes
For validation of wireless signals, a wireless receiver receives a validation signal that includes information from a target signal. By using digital signature, message authentication code (MAC), and/or hashing, the validation signal is verified to be from a trusted source. By comparing the information from the verified validation signal with the target signal, the target signal is confirmed to be genuine or not a spoofing signal. In one approach, the validation signal is provided from a different transmission source than the target signal. In another approach, modulation estimation rather than known modulation is used as the information for the validation signal for comparison with the target signal despite not knowing the spread pattern of the coding. In yet another approach, a one-way function is used to generate a pseudorandom code to spread a first component of the a first signal below the noise floor. The input to the one-way function is a second component sent at a time later than the time.
