Qualcomm Incorporated

Vinay Murthy

Raghuraman Krishnamoorthi

Linbo Li

Fuyun Ling

Ashok Mantravadi

Alok Kumar Gupta

Seong Taek Chung

Murali Chari

Bojan Vrcelj

Krishna Kiran Mukkavilli

Colin Beaton Verrilli

Natarajan Vaidhyanathan

Tao Tian

Phani Bhushan Avadhanam

Sandeep Pande

Satish Singh

A machine learning (ML)-accelerator system-on-chip (SoC) is described. The ML-accelerator SoC includes a set of ML-accelerator cores. The ML-accelerator SoC also includes a network-on-chip (NoC) coupled to the set of ML-accelerator cores. The ML-accelerator SoC further includes an inference video post processing (infVPP) module coupled to the NoC. The ML-accelerator SoC also includes a video decoder coupled to the NoC.

Hardware-based image/video processing in machine learning-accelerator system-on-chip

Methods and apparatus for power measurement in a communication system. In an aspect, a method is provided for power measurement. The method includes selecting between a signal decoding mode and a power measurement mode, decoding an input signal if the signal decoding mode is selected, and calculating a power measurement associated with the input signal if the power measurement mode is selected. In another aspect, an apparatus is provided for power measurement. The apparatus includes means for selecting between an active mode and a power measurement mode, means for decoding an input signal if the active mode is selected, and means for calculating a power measurement associated with the input signal if the power measurement mode is selected.

Methods and apparatus for power measurement in a communication system

Techniques for performing automatic gain control (AGC) at a wireless receiver are described. The total gain for the wireless receiver is achieved with discrete gain steps for analog circuitry and continuous gain for a digital variable gain amplifier (DVGA). An AGC loop is updated based on power measurements for an output signal from the DVGA. A first gain for the analog circuitry is selected from among multiple discrete gain values based on the AGC loop to maintain the average power of a baseband signal within a predetermined range at an analog-to-digital converter (ADC) input. A second gain for the DVGA is selected based on the AGC loop to maintain the average power of the output signal at a reference power level. The first gain is switched in a manner to avoid saturation of the ADC caused by the baseband signal and to provide switching hysteresis. The AGC may be performed in log domain and with multiple modes.

Automatic gain control for a wireless receiver

The disclosure is directed to a receiver, and methods therefor, including an automatic gain control circuit with a first digital variable gain amplifier that outputs digital samples based on a modulated wireless signal, an interference canceller configured to filter the digital samples using a least mean squares algorithm to reduce narrowband interference, and a second DVGA configured to amplify the filtered digital samples.

Narrow-band interference canceller

Techniques for performing frequency control using dual-loop automatic frequency control (AFC) are described. The dual-loop AFC includes an inner loop that corrects short-term frequency variations (e.g., due to Doppler effect) and an outer loop that corrects long-term frequency variations (e.g., due to component tolerances and temperature variations). In one design, a first inner loop is implemented for frequency control of a first system (e.g., a broadcast system), a second inner loop is implemented for frequency control of a second system (e.g., a cellular system), and at least one outer loop is implemented for adjusting a reference frequency used to receive signals from the first and second systems. Each inner loop estimates and corrects the frequency error in an input signal for the associated system and may be enabled when receiving the input signal from the system. The reference frequency may be used for frequency downconversion, sampling and/or other purposes.

Dual-loop automatic frequency control for wireless communication

The disclosure is directed to a mobile communication device that includes automatic gain control (AGC) circuitry and operates in either a tracking mode or an acquisition mode. A received signal is sampled n times to calculate an energy estimate that is used to set the gain control values within the AGC circuitry. The value of n varies depending on whether the handset is operating in the acquisition mode or the tracking mode. Acquisition mode is typically considered to be the mode prior to coarse timing acquisition, also referred to as frame acquisition.

Method and system for automatic gain control during signal acquisition

Techniques for performing frequency control in an OFDM system are described. In one aspect, frequency acquisition is performed based on a received pilot, and frequency tracking is performed based on received OFDM symbols. For frequency acquisition, an initial frequency error estimate may be derived based on the received pilot, and an automatic frequency control (AFC) loop may be initialized with the initial frequency error estimate. For frequency tracking, a frequency error estimate may be derived for each received OFDM symbol, and the AFC loop may be updated with the frequency error estimate. Frequency error in input samples is corrected by the AFC loop with the initial frequency error estimate as well as the frequency error estimate for each received OFDM symbol. In another aspect, a variable number of samples of a received OFDM symbol are selected, e.g., based on the received OFDM symbol timing, for use for frequency error estimation.

Automatic frequency control for a wireless communication system with multiple subcarriers

A control of an amplifier in an automatic gain control (AGC) loop, e.g. in the RF front end circuitry of an OFDM receiver, provides phase adjustment control data to an associated automatic frequency control (AFC), to compensate for a phase jump that would otherwise be caused by switching of the AGC gain between discrete gain states. In the disclosed example, for each gain state, comparators detect a signal energy estimate crossing either a high threshold or a low threshold. Upon threshold crossing, multiplexers select compensation data corresponding to the necessary transition from the prior state to the new state determined by the comparators, based on identification of the prior state and on the particular threshold that has been crossed (high or low). The phase compensation data supplied to the AFC, for one interval corresponding to the timing of the gain switching, adjusts phase rotation implemented in the AFC.

Phase compensation for analog gain switching in OFDM modulated physical channel

The disclosure is directed to a mobile communication device that includes automatic gain control (AGC) circuitry. Every n samples of the broadcast signals, an energy estimate of the AGC output signal is used to calculate and update a gain control value. Instead of using all n samples occurring subsequent to a previous gain control value update, only a subset of those n samples are used. In particular the first half of the n samples may be discarded in the energy estimate calculation while only the second half of the n samples may be used.

Method and system for automatic gain control with intelligent selection of signal samples

Systems and methods are provided for processing Time Domain Multiplexing (TDM) symbols via delayed correlation in the time domain. In one embodiment, a method is provided for determining synchronization information in an Orthogonal Frequency Division Multiplexing (OFDM) broadcast. The method includes employing a time domain correlation to detect the start of an OFDM super frame and utilizing the time domain correlation to synchronize a receiver to the carrier frequency of the OFDM signal.

Coarse timing/frame acquisition of OFDM system using time division multiplexed pilot symbol

Methods and apparatus for frequency tracking of a received signal. In an aspect, a method is provided wherein the received signal comprises one or more symbols having a periodic structure. The method comprises receiving a plurality of samples of a selected symbol that comprises pilot signals scrambled with data and determining a window size and a periodicity factor. The method also comprises accumulating a correlation between samples in a first window and samples in a second window to produce an accumulated correlation value, wherein the first and second windows have a size and a separation based on the window size and the periodicity factor, respectively, and deriving a frequency error estimate based on the accumulated correlation value.

Methods and apparatus for frequency tracking of a received signal

The disclosure is directed to a receiver. The receiver includes an interference canceller configured to filter digital samples produced from a modulated signal transmitted over a wireless channel, and a digital variable gain amplifier (DVGA) configured to amplify the filtered digital samples.

Techniques for performing automatic gain control are described. In some aspects, the gain control is achieved with an apparatus having an analog-to-digital converter (ADC) and a digital variable gain amplifier (DVGA), the DVGA configured to receive a digital signal from the ADC, the DVGA having a processor configured to compute a gain using a base n logarithm based on the power of the digital signal output from the ADC, the processor being further configured to apply the gain to the digital signal.

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San Diego, CA, United States of America

Vinay Murthy