A method, an apparatus and a computer program product for enhancing reception of signals in a wireless communication system. A signal containing a frame including a plurality of symbols is received on an uplink communication channel. An angular position of at least one symbol in the plurality of symbols in a constellation of symbols is detected. The plurality of symbols include equalized symbols. An angular difference corresponding a phase error between the detected angular position of the symbol and an expected reference angular position in the constellation of symbols corresponding to an expected reference symbol corresponding to the received frame is determined. Using the determined phase error, a phase of the symbol is compensated.

A system and method for transmitting an orthogonal frequency-division multiplexed signal with a group distributed phase tracking reference signal subcarrier structure, and for estimating, and compensating for, both common phase error, and inter-carrier interference.

A method for determining an angle of arrival (AOA) of a received signal is disclosed, comprising: generating a baseband information signal by mixing a received signal with a local oscillator (LO) signal, the received signal being an in-phase signal and quadrature signal uncorrelated with each other and derived from different input data sets; obtaining baseband signal samples of the baseband information signal having an in-phase signal sample and a quadrature signal sample; determining a transmitter phase offset based on an estimated correlation between the in-phase signal samples and the quadrature signal samples; performing a plurality of phase measurements using a plurality of antennas to obtain a plurality of phase measurements; correcting the plurality of phase measurements based on the transmitter phase offset to produce a plurality of corrected phase measurement; and calculating an AOA of the received signal based on the difference between the plurality of corrected phase measurements.

A carrier recovery system for a receiver of a phase-modulated signal N-PSK, the system including a first pre-conditioning circuit of the signal received (S(t)), with the pre-conditioned signal (SP(t)) having a component, non-modulated in phase, at the frequency N.sub.c where .sub.c is the carrier used for the modulation N-PSK, and a carrier regeneration circuit to regenerate two sinusoidal signals in quadrature at the frequency .sub.c, with these signals being phase locked with respect to said non-modulated component in phase of the pre-conditioned signal.

Channel estimation performance depends on the amount of averaging performed by a channel impulse response coherent filter. For half-duplex UEs, which use a single phase locked loop (PLL) for both downlink transmissions and uplink transmissions, averaging may not be performed across downlink subframes before and after uplink subframes if the PLL's phase changes and locks to a random initial value when switching transmission directions. Techniques disclosed herein facilitate estimating the PLL's random initial phase and enable correcting the phase of symbols accordingly. By correcting the phase of the symbols, it is possible to average across symbols before and after a frequency re-tune and/or a transmission direction switch based on the phase correction. This may serve to improve the accuracy of channel estimation. Further techniques disclosed herein may improve the accuracy of Doppler estimations by enabling the inclusion of symbols before and after a frequency re-tuning when performing the Doppler estimation.

A system and a method that enable two or more dispersed platforms to simultaneously use respective frequency-modulated continuous-wave radar systems in a typical radar application such as synthetic-aperture radar for terrain mapping, moving-target indicator radar to track targets on the ground and air-to-air tracking of other aircraft. The systems use the same RF spectrum in their operation and also communicate through their respective radar systems while simultaneously reducing their interplatform interference through the use of both filters and coded waveforms.

According to at least one example embodiment, a method and corresponding apparatus for controlling power in a multi-core processor chip include: accumulating, at a controller within the multi-core processor chip, one or more power estimates associated with multiple core processors within the multi-core processor chip. A global power threshold is determined based on a cumulative power estimate, the cumulative power estimate being determined based at least in part on the one or more power estimates accumulated. The controller causes power consumption at each of the core processors to be controlled based on the determined global power threshold. The controller may directly control power consumption at the core processors or may command the core processors to do so.

An OFDM system synchronization tracking method includes: A1: performing OFDM symbol segmentation on a received digital signal, performing FFT on OFDM symbols obtained through the segmentation, performing step A2 to A5 on each frequency domain OFDM symbol in a frequency domain OFDM symbol sequence; A2: extracting information subcarrier symbols, pilot symbols, a DC subcarrier from a current frequency domain OFDM symbol, detecting and implementing a decision on the information subcarrier symbols, generating a recovery information subcarrier symbol; A3: recovering the OFDM symbol; A4: performing frequency offset estimation and timing offset estimation on the recovery OFDM symbol; A5: performing phase compensation on a next frequency domain OFDM symbol in the frequency domain OFDM symbol sequence by using a frequency offset estimation phase rotation value and a timing offset estimation phase rotation value, setting the compensated frequency domain OFDM symbol to a current frequency domain OFDM symbol, returning to the step A2.

A method includes, at a frequency shift keying (FSK) demodulator, determining a likelihood of a symbol having a first symbol value or a second symbol value, using the likelihood of the symbol to select either the first symbol value or the second symbol value for the symbol, the first symbol value or the second symbol value that is selected being a selected symbol value, selecting a frequency error from a first frequency error or a second frequency error, and using a down-mixer and the frequency error to correct a frequency drift associated with a future selected symbol value.

A method includes, at a frequency shift keying (FSK) demodulator, determining a likelihood of a symbol having a first symbol value or a second symbol value, using the likelihood of the symbol to select either the first symbol value or the second symbol value for the symbol, the first symbol value or the second symbol value that is selected being a selected symbol value, selecting a frequency error from a first frequency error or a second frequency error, and using a down-mixer and the frequency error to correct a frequency drift associated with a future selected symbol value.