Abstract: A protection device for electrically insulating an antenna from a signal receiving device while transferring RF signals, and a system including the same are disclosed. In an embodiment, the protection device includes a first waveguide in signal communication and electrical communication with the antenna; and a second waveguide in signal communication and electrical communication with the signal receiving device. The first waveguide and the second waveguide are arranged in an end to end coaxial relationship facing one another, and the first waveguide and the second waveguide are electrically insulated from one another, such that a high voltage from accidental contact of the antenna with a power line cannot pass from the antenna to the signal receiving device. RF signals pass from the antenna to the signal receiving device through the protection device with minimal signal loss.

Abstract: Methods and systems for transmitting a spectrally efficient signal. The method includes frequency modulating an input signal in a transmitter to generate a first frequency modulated (FM) signal and generating in the transmitter an amplitude modulated (AM) component based at least on the input signal. The method may then include generating a second FM signal based at least on the AM component and the first FM signal and sending the second FM signal to a receiver.

Abstract: Methods and systems for transmitting a spectrally efficient signal. The method includes frequency modulating an input signal in a transmitter to generate a first frequency modulated (FM) signal and generating in the transmitter an amplitude modulated (AM) component based at least on the input signal. The method may then include generating a second FM signal based at least on the AM component and the first FM signal and sending the second FM signal to a receiver.

Abstract: A communication system enabling wireless transmission of messages via packets; and a method of operating the system provides for improved accuracy in the transmission of a message, particularly for overcoming signal distortion associated with the phase changes and varying multipath found in transmissions from the locomotive of a moving train. The maximum benefit of forward-error correction (FEC) with Reed-Solomon (RS) coding is applied for a message payload that is significantly shorter than the fixed length of a packet, with lesser coding being performed with longer payloads.

Abstract: A protection device for electrically insulating an antenna from a signal receiving device while transferring RF signals, and a system including the same are disclosed. In an embodiment, the protection device includes a first waveguide in signal communication and electrical communication with the antenna; and a second waveguide in signal communication and electrical communication with the signal receiving device. The first waveguide and the second waveguide are arranged in an end to end coaxial relationship facing one another, and the first waveguide and the second waveguide are electrically insulated from one another, such that a high voltage from accidental contact of the antenna with a power line cannot pass from the antenna to the signal receiving device. RF signals pass from the antenna to the signal receiving device through the protection device with minimal signal loss.

Abstract: An apparatus for reducing audio clicks in frequency modulated radio system includes a receiver for receiving a frequency modulated (FM) signal, and a processor for demodulating the received signal and estimating a frequency error, wherein the processor is configured to determine phase variations of the received FM signal by comparing a phase of a first signal sample to a phase of a second signal sample, wherein the first signal sample and the second signal sample are separated in time by more than one sample.

Abstract: An apparatus for reducing audio clicks in frequency modulated radio system includes a receiver for receiving a frequency modulated (FM) signal, and a processor for demodulating the received signal and estimating a frequency error, wherein the processor is configured to determine phase variations of the received FM signal by comparing a phase of a first signal sample to a phase of a second signal sample, wherein the first signal sample and the second signal sample are separated in time by more than one sample.

Abstract: A communication system enabling wireless transmission of messages via packets; and a method of operating the system provides for improved accuracy in the transmission of a message, particularly for overcoming signal distortion associated with the phase changes and varying multipath found in transmissions from the locomotive of a moving train. The maximum benefit of forward-error correction (FEC) with Reed-Solomon (RS) coding is applied for a message payload that is significantly shorter than the fixed length of a packet, with lesser coding being performed with longer payloads.