摘要:
A frontend module for Time Division Duplex (TDD) with Carrier Aggregation (CA), wherein the frontend module reuses the band selection filters for the aggregated bands and provides switched connections to antenna and transmitter/receiver according to the Uplink (UL)/Downlink (DL) configuration. The use of switches on both the antenna side and the transmitter/receiver side of the frontend module enables the reuse of the band selection filters. The frontend module according to the present invention reduces the number of required filters to only one filter for each TDD-CA Component Carrier (CC) band. Thus, the frontend module avoids unnecessary band selection filters, and thereby also controls the cost of implementation of frontend modules in wireless units operating in the TDD-CA mode.
摘要:
A frontend module for Time Division Duplex (TDD) with Carrier Aggregation (CA), wherein the frontend module reuses the band selection filters for the aggregated bands and provides switched connections to antenna and transmitter/receiver according to the Uplink (UL)/Downlink (DL) configuration. The use of switches on both the antenna side and the transmitter/receiver side of the frontend module enables the reuse of the band selection filters. The frontend module according to the present invention reduces the number of required filters to only one filter for each TDD-CA Component Carrier (CC) band. Thus, the frontend module avoids unnecessary band selection filters, and thereby also controls the cost of implementation of frontend modules in wireless units operating in the TDD-CA mode.
摘要:
Devices and methods for iteratively sampling a wideband signal in order to recover one or more narrowband signals are disclosed. In one aspect, a wideband signal is received and the signal is sampled using a sampling device, which includes an amplifier with an initial gain level, to produce a plurality of sampled signals. A first set of narrowband signals may be recovered from the plurality of sampled signals. Then, the wideband signal is re-sampled to produce a second plurality of sampled signals. The re-sampling includes increasing the gain of the amplifier to a second level and suppressing a component of the wideband signal. A second set of narrowband signals may then be recovered from the second set of sampled signals.
摘要:
Digital IQ imbalance estimation and compensation is facilitated by shaping the frequency response of receiver branches. In particular, in a multi-carrier receiver, the frequency response of signal processing elements in at least one receiver branch is set to not fully attenuate received signals in a frequency band of interest. The frequency band of interest is greater than the carrier bandwidth of the received signal processed by that receiver branch. In some embodiments, the received signal is not attenuated, and adjacent interfering signals are partially attenuated. This allows information regarding the interfering signals to appear in an IQ imbalance-induced, inter-carrier image of the signals in anther receiver branch, facilitating digital estimation and compensation of IQ imbalance.
摘要:
A device may include a measurement receiver, a communication receiver, and a transmitter. The measurement receiver may include a receiver (RX) down-conversion component to receive an amplified signal from a low-noise amplifier of the communication receiver, selectively receive a signal from a first local oscillator associated with the communication receiver or a second local oscillator associated with the transmitter, and down-convert the amplified signal to baseband using the received signal from the first local oscillator or the second local oscillator. The measurement receiver may further include a delta-sigma analog-to-digital converter (ADC) to provide low quantization noise only for a particular frequency range to be measured, and a control component to configure the delta-sigma ADC to provide the low quantization noise at the particular frequency range.
摘要:
Conventional mode adaptation does not account for the gain imbalance between channels for measurement and for data reception. Therefore, the precoder, which is selected based on the measurement channel, may not be the optimal precoder for the data reception channel. By maintaining relative SINR ordering between transmission modes, a receiver may select the transmission mode for a transmitter that maximizes the actual throughput even in the presence of inter-antenna gain increase or decrease.
摘要:
Systems and methods according to these exemplary embodiments provide for using demodulation reference signals (DM-RSs) to obtain channel state information (CSI) for precoder selection. A method includes: receiving a DM-RS in at least one subframe, determining the CSI from the DM-RS; and using the CSI to perform at least one function.
摘要:
Methods may be provided to transmit data from a wireless terminal operating in a radio access network. For example, sampling rate conversion may be performed on a serial stream of modulation symbols to generate sampling rate converted symbols, and the sampling rate converted symbols may be transmitted over a wireless channel to a node of the radio access network. Related terminals are also discussed.
摘要:
Embodiments of user equipment and methods for determining IQ imbalance parameters are described. In some embodiments, a method for determining in-phase (I) and Quadrature (Q) imbalance (IQ imbalance) parameters based on a known signal in a dual-carrier receiver using at least one controllable frequency offset includes receiving a known signal modulated onto a first radio frequency (RF) carrier frequency and a second RF carrier frequency different than the first RF carrier frequency; downconverting the known signal to a baseband signal for the first and second carriers by conversion from the respective RF carrier frequencies to an intermediate frequency (IF) using a common RF local oscillator (LO) and by further conversion from IF to baseband using carrier specific IF LOs, wherein as a controllable frequency offset is used as a part of the conversion from at least one of RF to IF and IF to baseband through the LOs; removing any controllable frequency offset from the baseband signal for the first and second carriers to produce representations of the received signals of the first and second carriers; and deriving IQ imbalance parameters for each representation of the received signals of the first and second carriers using a least square estimate.
摘要:
A system, method and node of single-carrier layer shifting for multiple-stream transmission in a network. Per-symbol layer shifting for multiple-stream transmission is implemented using DFTS-OFDM as an access technique. Code word-to-layer mapping is fixed within a DFTS-OFDM symbol and only shifted across consecutive DFTS-OFDM symbols. The method begins by receiving a multiple-stream transmission by a mapping module for transmission. The transmission includes a plurality of subframes and information carrying symbols transmitted on a plurality of layers. A per-symbol layer shifting scheme is then implemented on the transmission where layer shifting is conducted upon each symbol.