Methods and systems are provided for increasing bandwidth efficiency in satellite communications. In some embodiments, a satellite communications method is provided that comprises receiving, at a satellite and from a plurality of user ground terminals, a plurality of source signals, wherein each of the source signals are modulated according to at least one source modulation method, and further receiving, at a satellite and from a plurality of user ground terminals, a plurality of information signals corresponding to the plurality of source signals. The method further includes combining, at the satellite, the plurality of source signals into a combined source signal with an overlapping bandwidth, wherein each of the source signals are further modulated according to at least one predetermined modulation method before they are combined, and transmitting, by a downlink transmission from the satellite to a gateway ground station, the combined source signal.

An encoder operable to filter audio signals into a plurality of frequency band components, generate quantized digital components for each band, identify a potential for pre-echo events within the generated quantized digital components, generate an approximate signal by decoding the quantized digital components using inverse pulse code modulation, generate an error signal by comparing the approximate signal with the sampled audio signal, and process the error signal and quantized digital components. The encoder operable to process the error signal by processing delayed audio signals and Q band values, determining the potential for pre-echo events from the Q band values, and determining scale factors and MDCT block sizes for the potential for pre-echo events. The encoder operable to transform the error signal into high resolution frequency components using the MDCT block sizes, quantize the scale factors and frequency components, and encode the quantized lines, block sizes, and quantized scale factors for inclusion in the bitstream.

A frequency modulation circuit can include: a modulation circuit configured to generate a digital modulation signal and an analog modulation signal according to an input signal of the frequency modulation circuit; and a phase-locked loop having a voltage-controlled oscillator configured to receive a reference frequency, and to modulate a frequency of an output signal of the voltage-controlled oscillator according to the analog modulation signal and the digital modulation signal.

Methods, systems, and bitstream syntax are described for canvas size, single layer or multi-layer, scalable decoding, with support for regions of interest (ROI), using a decoder supporting reference picture resampling. Offset parameters for a region of interest in a current picture and offset parameters for an ROI in a reference picture are taken into consideration when computing scaling factors to apply reference picture resampling. Syntax elements for supporting ROI regions under reference picture resampling are also presented.

Provided is a transform coefficient scan method including: determining a reference transform block for a decoding target block; deriving a scanning map of the decoding target block using scanning information of the reference transform block; and performing inverse scanning on a transform coefficient of the decoding target block using the derived scanning map. According to the present invention, picture encoding/decoding efficiency may be improved.

A communication management resource implements an iterative process to derive settings for digital precoder W, analog precoder A, and decode function D with a bandwidth-limited fronthaul link between the application of digital precoder W and the application of analog precoder A. The iterative process includes: for a first instance of digital precoder W and decode function D, optimize an instance of the analog precoder A; and based on the optimized instance of the analog precoder A, optimize a second instance of the digital precoder W and the decode function D. In one implementation, for each iteration of multiple iterations, the communication management resource: i) optimizes an instance of the analog precoder A based on an instance of the digital precoder W and the decode function D, and ii) optimizes an instance of the digital precoder W and the decode function D based on the instance of the analog precoder A.

Radio frequency (RF) communication systems with coexistence management are provided herein. In certain embodiments, a method of coexistence management in a mobile device includes processing a wireless local area network (WLAN) observation signal to generate WLAN observation data using a WLAN observation channel of a WLAN transceiver, processing an RF cellular receive signal to generate a digital baseband cellular receive signal using a cellular receive channel of a cellular transceiver, processing a cellular observation signal to generate cellular observation data using a cellular observation channel of the cellular transceiver, and compensating the digital baseband cellular receive signal for RF signal leakage based on the WLAN observation data and on the cellular observation data using a discrete time cancellation circuit of the cellular transceiver.

An encoder operable to filter audio signals into a plurality of frequency band components, generate quantized digital components for each band, identify a potential for pre-echo events within the generated quantized digital components, generate an approximate signal by decoding the quantized digital components using inverse pulse code modulation, generate an error signal by comparing the approximate signal with the sampled audio signal, and process the error signal and quantized digital components. The encoder operable to process the error signal by processing delayed audio signals and Q band values, determining the potential for pre-echo events from the Q band values, and determining scale factors and MDCT block sizes for the potential for pre-echo events. The encoder operable to transform the error signal into high resolution frequency components using the MDCT block sizes, quantize the scale factors and frequency components, and encode the quantized lines, block sizes, and quantized scale factors for inclusion in the bitstream.

An image decoding method performed by a decoding apparatus according to the present document comprises the steps of: obtaining a flag indicating whether quantization parameter data for combined chroma coding is present on the basis of a type of chroma; obtaining the quantization parameter data for the combined chroma coding on the basis of the flag; deriving a chroma quantization parameter table on the basis of the quantization parameter data; deriving a quantization parameter for the combined chroma coding on the basis of the chroma quantization parameter table; deriving residual samples on the basis of the quantization parameter; and generating a reconstructed picture on the basis of the residual samples.

Efficient processing of chroma-subsampled video is performed using convolutional neural networks (CNNs) in which the luma and chroma channels are processed separately. The luma channel is independently convolved and downsampled and, in parallel, the chroma channels are convolved and then merged with the downsampled luma to generate encoded chroma-subsampled video. Further processing of the encoded video that involves deconvolution and upsampling, splitting into two sets of channels, and further deconvolutions and upsampling is used in CNNs to generate decoded chroma-subsampled video in compression-decompression applications, to remove noise from chroma-subsampled video, or to upsample chroma-subsampled video to RGB 444 video. CNNs with separate luma and chroma processing in which the further processing includes additional convolutions and downsampling may be used for object recognition and semantic search in chroma-subsampled video.