The various embodiments herein disclose methods and systems for uplink scheduling schemes for low-earth orbit (LEO) satellite based Non-Terrestrial Network (NTN). According to an embodiment, a zone-based scheduling (ZBS) scheme is described where the coverage area may be divided into a plurality of zones and independent scheduling-offsets may be allocated for each of the zones. The ZBS scheme improves upon the overall user latency by reducing the K2 and cell offset delay for low-propagation delay users within the NTN cells. At the same time, the impact of differential doppler may also be mitigated with such a zone-based allocation strategy.

Systems and methods for a non-data-aided (NDA) approach to advanced OFDM timing are provided. This approach allows for accurate OFDM symbol timing and synchronization by avoiding inter-symbol interference (ISI) in multipath environments where an earliest arriving signal may not be the strongest signal. The NDA approach may rely on generating and applying a bias correction to a combined correlation result of the multi-path signals.

Methods, systems, and devices for satellite operations are described. A satellite communications system may include a transmitter that applies multiple spreading codes to a data signal to obtain multiple spread data signals. The transmitter may transmit the multiple spread data signals from multiple antenna elements in a composite signal. The satellite communications system may also include a receiver that receives the composite signal and applies multiple despreading codes to the composite signal to obtain multiple despread data signals. The receiver may combine the multiple despread data signals to obtain a combined data signal that corresponds to the data signal processed by the transmitter. To combine the multiple despread data signals, the receiver may estimate coefficients for each of the despread data signals.

Satellites in a non-terrestrial network may provide positioning reference signals (PRS) to user equipment (UE), with which the UE may determine its position using propagation delay difference measurements, such as Time Difference of Arrival (TDOA) measurement. Due to the large distances between satellites and the UE, the propagation delay differences in the PRS received from satellites may exceed half a radio frame, resulting in a frame level timing ambiguity in the differential measurements. The satellites transmit secondary PRS, along with primary PRS, that include timing information to resolve frame level timing ambiguity of the primary PRS. The positioning occasions in the secondary PRS, for example, may be aligned with corresponding positioning occasions primary PRS within each radio frame, and are transmitted with a periodicity that is an integer multiple (greater than 1) of that of the primary PRS to resolve the frame level timing ambiguity of the primary PRS.

Techniques are provided for reacting to a notification of a timing source outage in a network node. An example method for reacting to an indication of a timing source outage includes receiving the indication of the timing source outage associated with a first node, and deactivating at least one transmission from the first node.

Various arrangements of transmit and receive shared-aperture array antenna systems are presented herein. The arrangements can include an antenna that includes: a planar substrate; a first row of a first plurality of transmit patches arranged on the planar substrate; a second row of a plurality of receive patches arranged on the planar substrate; and a third row of a second plurality of transmit patches arranged on the planar substrate. The first row, second row, and third row can be parallel and the second row can be between the first row and the third row.

The present teachings disclose a multibeam satellite system and methods that can achieve orthogonality between spatially multiplexed signals in a multi-input multi-output (MIMO) configuration when operating in line-of-sight (LOS) uplink and downlink channels on the feeder link side, using essentially a common spot beam. The teachings maximize a MIMO capacity across multiple frequency bands by disclosing an antenna array geometry for disposition on-board a single satellite and for a ground segment.

A method for performing an uplink transmission by a user equipment in a non-terrestrial network, a method for scheduling uplink transmission in a non-terrestrial network, a user equipment and a base station are provided. The method comprises: receiving, from a base station, a first information for indicating uplink transmission resources, and a second information, wherein the second information comprises a first parameter for indicating the uplink transmission resources; performing, based on the first information and the second information, an uplink transmission on the uplink transmission resources.

Provided in embodiments of the present disclosure are a wireless communication method, a terminal device, and a network device. The wireless communication method includes: determining, by a terminal device, a start time of a time window for random access according to a first Round Trip Time (RTT) offset value, or determining, by the terminal device, the start time of the time window for random access according to a first RTT offset value group. Each RTT offset value in the first RTT offset value group corresponds to an RTT interval, respectively.

The present application relates to devices and components including apparatus, systems, and methods for ephemeris signaling in wireless networks.