A system or method for generating or distributing GNSS corrections can include or operate to: generate a set of corrections based on satellite observations, wherein each correction of the set of corrections comprises an area associated with the correction, a tag, and correction data; update a set of stored corrections with the set of received corrections based on a tag associated with each correction of the set of stored corrections and the tag associated with each correction of the set of received corrections; and transmit stored corrections of the set of stored corrections to the GNSS receiver when the area associated with the stored corrections matches the locality of the GNSS receiver.

A method of receiving two chip-by-chip multiplexed CSK signals (e.g., GNSS signals) and searching for a non-CSK signal with optimal performance at a given digit capacity of a sampling memory resided in parallel correlators. For CSK signals Prompt, Early and Late results for each of possible code shift are calculated as different sums of four punctured convolutions. Depending on configuration, the method allows to receive both multiplexed CSK signals with lesser quality or one of the CSK signals with better quality. The method can be implemented as an apparatus with four punctured correlators, a set of multipliers by 1 or 2.sup.N, another set of multipliers by 1 or 0, summers of four input to one result, a RAM, searchers of maximum, and conditional commutators.

The presence or absence of a preamble is detected with accuracy in a reception apparatus that receives a signal including a preamble. A reception section receives a subframe including a subframe preamble and a message and a frame including a frame preamble. A processing section performs a process of detecting the presence or absence of the subframe preamble according to whether or not a given relation holds between a reception timing of the subframe preamble and a reception timing of the frame preamble. A message decoding section extracts the message from the subframe and decodes the message in a case where the presence of the subframe preamble is detected.

A non-systematic convolutional decoder of a convolutionally encoded multi-level data stream includes a shift register and two or more paths of exclusive-OR (XOR) gates, arranged to reconstruct an original input information stream, each path having a quantiser arranged to quantise the signal to two levels, and a set of XOR gates arranged to match an encoding path in an associated convolutional encoder, and a selector arranged to feed an output from each path to a single input of the shift register. If the paths have differing values at their output, the selector may choose the value from the path based upon a function of the multi-level signals associated with each path, such as the path with the largest absolute signal level. The decoder provides a simple means for decoding signals while allowing the signal to also or instead be decoded using e.g. a Viterbi decoder if higher performance is required.

A method and apparatus are provided for demodulating an L1S signal from a satellite in the Quasi-Zenith Satellite System (QZSS). The method comprises tracking another L1 signal transmitted by the satellite, and predicting, based on the tracking parameters of the other L1 signal, one or more parameters of the L1S signal. The L1S signal is demodulated based on the one or more predicted parameters.

A method and apparatus are provided for demodulating a B2b signal from a satellite in the BeiDou Navigation Satellite System. The method comprises tracking a first signal transmitted in a first GNSS operational band by the satellite, to estimate one or more parameters of the first signal; predicting, based on the estimated one or more parameters of the first signal, one or more parameters of the B2b signal transmitted by the satellite; and demodulating the B2b signal to obtain data bits of a data message modulated on the B2b signal by the satellite. The demodulating is based on the one or more predicted parameters of the B2b signal.

Apparatus and method for communication in non-terrestrial networks are disclosed. A set of Doppler shift curves for different distances to one or more satellite orbits is obtained. Measurements of satellite transmission are performed to obtain estimate of instantaneous Doppler shift of the transmission, the measurements including a timestamp. A Doppler shift curve corresponding to the measurements is calculated. A time offset on the selected curve is determined utilising the timestamps of the measurements, the time offset indicating the position of the Doppler shift of the apparatus on the curve. The Doppler shift of the satellite transmission is determined utilising the selected curve and the time offset.

An electronic device includes a global positioning system (GPS) processor to establish locality and a GPS capture controller to isolate a pre-defined personalized proximal network with axial cardinal orientation. A display presents the proximal network of co-inhabitants at interface, and a touch-controller allows for the haptic contact selection of alternate user icon(s) to execute telecommunication between distinguishable users within the proximal field through associative geographic identity.

System and method for concurrently protecting Iridium and GPS L1/L2 band received satellite signals against interference signals (e.g., jamming signals) using space-time adaptive processing (STAP). While the GPS signal is protected against jamming using Nulling of the interfering signals, the Iridium signal is protected using Beamforming. A single broadband small controlled reception pattern antenna (sCRPA) array receives both the GPS (L1 and L2) and Iridium signals for the STAP-based antijam solutions outputting filtered Iridium and GPS signals. Use of a common (small) broadband antenna and common front end signal processing of the received signals enables an integrated system for use on size, weight, and power constrained platforms such as drones, unmanned aerial vehicles (UAVs), and helicopters.

A method and transmission system for amplifying and providing navigation signals. The system comprises a splitter circuit configured to receive a plurality of radio frequency (RF) signals oscillating at at least two different frequencies f.sub.1 and f.sub.2. The splitter circuit is further configured to split and forward the RF signals having the f.sub.1 frequency to a first bandpass filter and the RF signals having the f.sub.2 frequency to a second bandpass filter. The system further comprises a first tunable amplifier configured to receive the RF signals from the first bandpass filter. The system further comprises a second tunable amplifier configured to receive the RF signals from the second bandpass filter at substantially the same time as the first tunable amplifier's receipt of the RF signals from the first bandpass filter. The first tunable amplifier is further configured to amplify its RF signals across a first band centered around the frequency f.sub.1. The second tunable amplifier is further configured to amplify its RF signals across a second band centered around the frequency f.sub.2. The amplified RF signals are fed substantially concurrently into a mixer circuit for transmission via an RF antenna to a navigation receiver.