摘要:
Techniques are provided for providing Doppler correction. In particular, embodiments may provide re-banding circuitry having a reference clock, a mixer, and a compensation circuitry for re-banding and for Doppler correction. The compensation circuitry may be configured to adjust a reference frequency of the reference clock based on signals received from a Global Navigation Satellite System (GNSS) receiver. The mixer may be configured to translate communication signals in a first frequency band to a second frequency band based at least in part on the adjusted reference frequency of the reference clock.
摘要:
Embodiments of the present disclosure describe systems, devices, and methods that may provide channel estimation and compensation in high speed scenarios, which may include user equipment carried on a high speed train. Embodiments may employ cell-specific reference signal (CRS)-based time-domain channel estimation and compensation.
摘要:
Aspects of the subject disclosure may include, for example, a coupling device including a first antenna that radiates a first RF signal conveying first data; and a second antenna that radiates a second RF signal conveying the first data from the at least one transmitting device. The first RF signal and second RF signal form a combined RF signal that is bound by an outer surface of a transmission medium to propagate as a guided electromagnetic wave substantially in a single longitudinal direction along the transmission medium. Other embodiments are disclosed.
摘要:
A method for compensating Doppler shifts (v) in a mobile communication system comprises the steps of: receiving a mobile communication signal (y); transforming the signal in order to compensate a Doppler shift (v p ) of at least one propagation path (p) of the signal (y); and outputting the compensated signal. A matching pursuit (MP) algorithm is used for estimating Doppler shifts of propagation paths (p) of the signal.
摘要:
The invention discloses a method and a base station for phase compensation in beamforming in a multi-antenna Time Division Duplex (TDD) communication network. In a first transmission mode, e.g. TM4 or TM8, the base station estimates a first phase shift between a first antenna port and a reference antenna port in uplink based on a measurement of a first Sounding Reference Signal (SRS). Then the base station estimates in the first transmission mode a second phase shift between the first antenna port and the reference antenna port in downlink based on a Channel State Information (CSI) feedback from a User Equipment (UE), and calculates a parameter indicative of a difference between the first phase shift and the second phase shift. In a second transmission mode, e.g. TM7 or TM8, the base station estimates a third phase shift between the first antenna port and the reference antenna port in uplink based on a measurement of a second SRS, and calculates in the second transmission mode, a fourth phase shift between the first antenna port and the reference antenna port in downlink as a difference between the third phase shift and the parameter. The base station then compensates in the second transmission mode, the phase of input signal on the first antenna port by the fourth phase shift for beamforming.
摘要:
A method of providing Doppler compensation in a wireless network by determining first and second -Doppler compensation factors for a first and second user group in response to traffic data associated with each user group, and transmitting data from the base station to each user group at a frequency adjusted by each Doppler compensation factor.
摘要:
A technique for performing a random access procedure in a fast moving mobile device (100) in context with accessing a radio base station (101 ) is described. A method embodiment of the technique comprises tuning a receiver (106) of the mobile device (100) to an expected frequency of a pilot signal (136) provided by the base station (101 ); determining, based on an output signal of the receiver (140), a feedback signal (142) for locking the receiver (106) to a receive frequency of the pilot signal (136); providing the feedback signal (148) to a transmitter (108) of the mobile device (100); and adjusting a transmission frequency of a random access signal (154) according to a frequency offset between the expected frequency and the receive frequency of the pilot signal (136) indicated by the feedback signal (148).