A frequency hopping device is co-located with a set of frequency hopping devices, and includes a controller that is configured to identify from a plurality of channels, first and second sets of channels that are available and unavailable for an adaptive frequency hopping (AFH) operation associated with the frequency hopping device, respectively. The controller is further configured to assign a lowest priority level to each channel of the second set of channels, an intermediate priority level to each channel of the first set of channels that is to be utilized by the set of frequency hopping devices, and a highest priority level to each remaining channel of the first set of channels. Further, the controller is configured to generate an AFH map based on a number of channels that have the highest priority level, and execute the AFH operation based on the AFH map.

A radio-transmitting device comprises a radio interface operating in a predetermined frequency band, operatively arranged for modulating a carrier having a frequency in the frequency band, while switching the frequency of the carrier among several hopping frequencies in the frequency band, according to a hopping sequence, to obtain a spread-spectrum modulated signal, wherein the spread-spectrum modulated signal includes, in a preamble portion, a plurality of sync words, each combined with at least one instance of a sequential index, the sync words being transmitted at different frequencies, and a data portion following the preamble portion and including a plurality of frequency hops.

A pre-distortion processing device, a signal transmission system, and a pre-distortion processing method are provided. The pre-distortion processing device comprises a pre-distortion unit, a transmission unit and a coupling unit which are sequentially connected. A feedback path of the coupling unit is connected to the pre-distortion unit. The pre-distortion processing device further comprises a generation unit and a combiner unit. The generation unit is used to generate a non-hopping wideband signal having a bandwidth greater than a bandwidth of a system input signal. A first input terminal of the combiner unit is connected to an output terminal of the generation unit. A second input terminal of the combiner unit is used to receive the system input signal. An output terminal of the combiner unit is connected to an input terminal of the pre-distortion unit.

Provided is a jamming defense system. In the jamming defense system for wireless local area network communication between an access point (AP) and a user node, the AP that transmits and receives a message to and from the user node generates an AP secret key value by measuring a signal reception strength for the message, and the user node that transmits and receives a message to and from the AP generates a user node secret key value by measuring a signal reception strength for the message.

A method for mitigating interference in a frequency hopping channel system based on codeword metrics obtained during decoding of codewords. The method includes decoding a plurality of codewords using a particular error control coding method. Each of the plurality of codewords includes portions received from plurality of channels in the frequency hopping channel system. For each decoded codeword, one or more codeword metrics are obtained based on the cost of correcting errors during decoding of the plurality of codewords. Based on the codeword metrics, one or more channel metrics are inferred. Based on the inferred one or more channel metrics, a reliability metric of a particular channel is reduced, or incoming symbols received from the particular channel are ignored during decoding.

A system and method of index modulation based joint mode frequency hopping with vortex electromagnetic waves for anti-jamming are provided. The system is additionally provided with a transmit signal carrier selector that provides diversified options, a receive signal carrier selector that is strictly synchronized with the transmit signal carrier selector, and a group of fast Fourier transformation modules to output a binary demodulation signal with jamming eliminated. The method includes: binary information division; index modulation and information modulation; information loading and hopping; information transmission, de-hopping, and jamming filtering; and calculation of the jamming probability and an average bit error rate. The present disclosure combines orbital angular momentum modes and subcarrier frequencies to form OAM mode-subcarrier frequency pair sets so as to diversify information transmission carriers, and performs simultaneously modulation and hopping to increase a spectrum efficiency and enhance the anti-jamming capability.

A method of operating a radio receiver device comprises receiving a plurality of signals with a plurality of corresponding frequencies; applying respective gains to each of the plurality of signals; and storing the gain applied to each signal and its corresponding frequency. The method comprises subsequently receiving a further signal with a further frequency; and applying a further gain to the further signal. The further gain is determined using at least one of the stored gains according to a difference between the further frequency and at least one of the plurality of corresponding frequencies.

Suppressing interference in a frequency hopping signal. The method includes receiving a frequency hopping signal for a signal of interest. The frequency hopping signal includes the signal of interest modulated using frequency hopping and wideband and narrowband interference. Prior to de-hopping the frequency hopping signal, one or more wideband interferences in the frequency hopping signal are identified. The one or more wideband interferences are suppressed to create a wideband interference suppressed signal. Subsequent to suppressing the one or more wideband interferences, the wideband interference suppressed signal is de-hopped to create a de-hopped signal. In the de-hopped signal, one or more narrowband interferences are identified. The one or more narrowband interferences are suppressed to create an interference suppressed signal. The interference suppressed signal is demodulated to create a demodulated signal.

A frequency hopping device is co-located with a set of frequency hopping devices, and includes a controller that is configured to identify from a plurality of channels, first and second sets of channels that are available and unavailable for an adaptive frequency hopping (AFH) operation associated with the frequency hopping device, respectively. The controller is further configured to assign a lowest priority level to each channel of the second set of channels, an intermediate priority level to each channel of the first set of channels that is to be utilized by the set of frequency hopping devices, and a highest priority level to each remaining channel of the first set of channels. Further, the controller is configured to generate an AFH map based on a number of channels that have the highest priority level, and execute the AFH operation based on the AFH map.

A system and method of index modulation based joint mode frequency hopping with vortex electromagnetic waves for anti-jamming are provided. The system is additionally provided with a transmit signal carrier selector that provides diversified options, a receive signal carrier selector that is strictly synchronized with the transmit signal carrier selector, and a group of fast Fourier transformation modules to output a binary demodulation signal with jamming eliminated. The method includes: binary information division; index modulation and information modulation; information loading and hopping; information transmission, de-hopping, and jamming filtering; and calculation of the jamming probability and an average bit error rate. The present disclosure combines orbital angular momentum modes and subcarrier frequencies to form OAM mode-subcarrier frequency pair sets so as to diversify information transmission carriers, and performs simultaneously modulation and hopping to increase a spectrum efficiency and enhance the anti-jamming capability.