Showing papers by "Chester Park published in 2013"

Carrier aggregation for LTE-advanced: design challenges of terminals

Abstract: Carrier aggregation is a key feature of 3GPP LTE that addresses the support of higher data rates and utilization of fragmented spectrum holdings. In this article, the relevant design challenges of terminals are discussed. The transmitter architectures are reviewed, and the minimum amount of power amplifier back-offs is evaluated. In addition, several receiver architectures are compared from the perspective of design tradeoff. The radio impairments affecting the receiver performance are analyzed and the simulation results are provided. The corresponding silicon implementation is presented together with the measurement results.

A radio node, a user equipment and methods for managing a transmission

Abstract: A radio network node (110), a user equipment (120) and methods therein for managing a transmission from the user equipment (120) to the radio network node (110) are disclosed. The radio network node (110) adapts (302) a transport format relating to the transmission based on information indicating at least one mode switching point of a radio transmitter (1420). The radio transmitter (1420) is comprised in the user equipment (120). The user equipment (120) adapts (311) the transmission based on the information indicating at least one mode switching point of the radio transmitter (1420) comprised in the user equipment (120).

Methods and devices for adjusting resource management procedures based on machine device capability information

Abstract: Devices and methods for adjustmeresoarce management procedures based on machine device capability information are disclosed. In one aspect, a method for adjusting resource management procedures in a machine device communicating with a node operating in a communication network includes receiving a first message from the machine device, the first message including machine device capability information, processing the received machine device capability information to determine an adjustment to a resource management procedure, and transmitting a second message to the machine device, the second message including the determined resource management procedure adjustment- The first and second messages may be radio resource control (RRC) messages, such as RRC connection request and setupmessages.

Adjusting ue transmission and reception based on ue self interference

Abstract: Systems and methods for mitigating self-interference at a wireless device in a cellular communications network are disclosed. In one embodiment, a network node obtains one or more self-interference parameters for self-interference at the wireless device within a downlink frequency band utilized by the wireless device. In one embodiment, the one or more self-interference parameters include a frequency location of the self-interference, a strength of the self-interference, or both the frequency location and the strength of the self-interference. The network node then controls uplink transmission by the wireless device, downlink reception by the wireless device, and/or downlink transmission to the wireless device in such a manner that the self-interference at the wireless device is mitigated.

Combining channel quality measurements based on sounding reference signals and demodulation reference signals

Abstract: Methods of operating a first communication node are disclosed. The first communication node communicates by multiple-input-multiple-output (MJMO) wireless communications with a second communication node of a wireless communication system. The method includes receiving a Sounding Reference Signal (SRS) over a plurality of subcarriers transmitted by the second communication node for MIMO communications. Channel quality is measured responsive to the sounding reference signal to output a first channel quality value. A demodulation reference signal is received over a plurality of subcarriers transmitted by the second communication node for MIMO communications. Channel quality is measured responsive to the demodulation reference signal to output a second channel quality value. Reliability of the measurements of the first channel quality value and the second channel quality value is determined. The first channel quality value and the second channel quality value are combined while compensating for the determined reliability difference between the measurements to generate a combined channel quality value. Related communication nodes are disclosed.

Weighted rsrp measurement

Abstract: Systems and methods are disclosed for measuring received signal power at a mobile terminal in a cellular communications network in such a manner as to efficiently provide highly accurate received signal power measurements in the presence of strong inter-cell interference. In one embodiment, in order to measure received signal power for a measured cell, a mobile terminal selects weighting parameters for a number of time-frequency samples of a reference signal of the measured cell based, at least in part, on inter-cell interference from one or more synchronized interfering cells and inter-cell interference from one or more non-synchronized interfering cells. The mobile terminal applies the time-frequency samples of the reference signal of the measured cell and the corresponding weighting parameters to corresponding time-frequency samples of a received signal from the measured cell in order to obtain a measurement of the received power for the measured cell.

Systems and methods for mitigating self-interfernece

Abstract: Systems and methods for mitigating self-interference at a wireless device (14) in a cellular communications network (10) are disclosed. In one embodiment, a network node (12, 14) obtains one or more self-interference parameters for self- interference at the wireless device (14) within a downlink frequency band utilized by the wireless device (14). In one embodiment, the one or more self-interference parameters include a frequency location of the self-interference, a strength of the self- interference, or both the frequency location and the strength of the self-interference. The network node (12, 14) then controls uplink transmission by the wireless device (14), downlink reception by the wireless device (14), and/or downlink transmission to the wireless device (14) in such a manner that the self-interference at the wireless device (14) is mitigated.

Adaptive precoder cycling

Abstract: Methods and apparatus are disclosed for improving a precoder selection process in a wireless communications system, in a normal precoder selection process, a precoder is selected from a codebook based on channel state information estimated from received reference signals. In between two received reference signals, a subset of precoders is cycled through and each precoder in the subset is iteratiyely selected for use by a transmitter to precede transmit signals. The subset of precoders may be adaptively modified based on predefined criteria.

A Calibration Technique for Multibit Stage Pipelined A/D Converters via Least-Squares Method

Abstract: This brief presents a foreground calibration method for correcting linear and memoryless errors in multibit stage pipelined A/D converters (ADCs). Using a least-squares minimization, the method extends the radix-based pipelined ADC calibration to multibit stage architectures by adopting one-of- n encoding with a radix vector expansion, thereby correcting both nonideal stage gain and random code-boundary transitions in a globally optimal sense. Numerical experiments via Monte Carlo simulation of 400 ADCs show that the proposed calibration method can improve the effective number of bits from 9.5 b to 14.4 b for a hypothetical 15-b 200-MS/s pipelined ADC design in 90-nm CMOS process.

Dfts-ofdm using sampling rate conversion

Abstract: Methods and devices are provided in which the DFT-SODFM signal is generated through Px upsampling of QAM symbols s[m], frequency offsetting the up sampled QAM symbols, digital filtering with circular convolution with rotated filter coefficients and Qx down sampling. Variants are possible exploiting linear convolution.