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.

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.

The apparatus may be a base station. The apparatus processes a first group of synchronization signals. The apparatus processes a second group of synchronization signals. The apparatus performs a first transmission by transmitting the processed first group of the synchronization signals in a first synchronization subframe. The apparatus performs a second transmission by transmitting the processed second group of the synchronization signals in a second synchronization subframe.

The apparatus may be a base station. The apparatus processes a first group of synchronization signals. The apparatus processes a second group of synchronization signals. The apparatus performs a first transmission by transmitting the processed first group of the synchronization signals in a first synchronization subframe. The apparatus performs a second transmission by transmitting the processed second group of the synchronization signals in a second synchronization subframe.

A device in a population of devices arranged at a celestial body for transmitting data to a relay station orbiting the celestial body. The relay station and the population of devices are to travel with respect to one another such that the relay station is to receive signals that include the data in data packages from the population of devices. The device includes trajectory data of the relay station, a transmitter to use the trajectory data so as to transmit a signal that is part of the signals, a data processor, and a computer program which, when executing on the data processor, is to calculate a Doppler shift based upon the trajectory data, and modify the signal to thereby compensate for the Doppler shift of the signal that results from the travelling of the relay station and the population of devices with respect to one another.

A device in a population of devices arranged at a celestial body for transmitting data to a relay station orbiting the celestial body. The relay station and the population of devices are to travel with respect to one another such that the relay station is to receive signals that include the data in data packages from the population of devices. The device includes trajectory data of the relay station, a transmitter to use the trajectory data so as to transmit a signal that is part of the signals, a data processor, and a computer program which, when executing on the data processor, is to calculate a Doppler shift based upon the trajectory data, and modify the signal to thereby compensate for the Doppler shift of the signal that results from the travelling of the relay station and the population of devices with respect to one another.

Methods, systems, and apparatus, including computer programs encoded on computer-storage media, for bandwidth allocation using machine learning. In some implementations, a request for bandwidth in a communications system is received. Data indicative of a measure of bandwidth requested and a status of the communication system are provided as input to a machine learning model. One or more outputs from the machine learning model indicate an amount of bandwidth to allocate to the terminal, and bandwidth is allocated to the terminal based on the one or more outputs from the machine learning model.

The apparatus may be a base station. The apparatus processes a first group of synchronization signals. The apparatus processes a second group of synchronization signals. The apparatus performs a first transmission by transmitting the processed first group of the synchronization signals in a first synchronization subframe. The apparatus performs a second transmission by transmitting the processed second group of the synchronization signals in a second synchronization subframe.

The apparatus may be a base station. The apparatus processes a first group of synchronization signals. The apparatus processes a second group of synchronization signals. The apparatus performs a first transmission by transmitting the processed first group of the synchronization signals in a first synchronization subframe. The apparatus performs a second transmission by transmitting the processed second group of the synchronization signals in a second synchronization subframe.

The present disclosure describes the concept of operations and the medium access control protocols of a wireless communication system using code-division multiple access with interference avoidance (CDMA-IA) as its physical layer. The system can dynamically share a common band with other networks without a central radio resource controller. In one embodiment, the wireless communication system includes a plurality of radio nodes forming a wireless mesh network, wherein the pairs of radio nodes use, individually optimized, time division duplexing. At least one radio node includes a software-defined radio, a memory, and an electronic processor. The electronic processor is configured to control the software-defined radio to transmit a pilot signal and share various state information with the other nodes of the network. The shared information includes local spectrum occupancy and node connectivity sets. The pervasive sharing of spectrum occupancy among all nodes enables the usage of the shared band to be maximized.