Lucent Technologies Inc.

Alcatel Lucent

Hong Kong Applied Science and Technology Research Institute

Alcatel-Lucent USA Inc.

Henry Hui Ye

Fang-Chen Cheng

Hongwei Kong

Subramanian Vasudevan

Jialin Zou

Lei Song

Cheng Wang

Kai Zhang

Lily H Zhu

Rainer Walter Bachl

Francis Dominique

Anil M Rao

Stanley Vitebsky

Jung Ah Lee

Said Tatesh

Mirko Schacht

Wing Chau Chan

Yunsong Yang

Kumud Kumar Sanwal

Lawrence J Merboth

Xue-yuan Zhao

This invention describes method and apparatus for automatic gain control (AGC) for a TD-LTE system, taking into consideration the TD-LTE frame structure. In one embodiment, an AGC method comprises: adjusting RF gain for subframe j (where 0&#x3c;=j&#x3c;=9) in a radio frame according to an average peak signal power of subframe j in previous radio frames when a terminal is lack of information in downlink timing and in uplink/downlink configuration; computing a first average signal power in one or more downlink subframes as received from at least one base station when the terminal has information in downlink timing but is lack of information in uplink/downlink configuration; and computing a second average signal power in one or more downlink subframes as received from at least one base station when the terminal has information in downlink timing and in uplink/downlink configuration.

Method and apparatus for automatic gain control in a TD-LTE system

The present invention relates to a method and apparatus for channel temporal correlation estimation and MIMO mode selection. An embodiment of the invention under LTE system utilizes SRS symbols for temporal correlation estimation and performs MIMO mode selection based on the said temporal correlation estimation.

Method and apparatus for estimation of channel temporal correlation and MIMO mode selection in LTE system

The present invention relates to a method of channel estimation comprising two major steps. The first step is the least-squared and minimum mean-square error (MMSE) estimations on the pilot resource elements to generate the channel response estimates at the predefined pilot locations. The second step of the channel estimation, which utilizes the results from the first step to compute the channel response estimates for the remaining resource elements, comprises the following three operations: (i) averaging of each pair of adjacent pilot resource elements in the frequency direction to obtain the channel response estimate of the resource element in the middle of those two pilot resource elements; (ii) MMSE interpolation in the time domain for all the sub-carriers containing pilot signals; and (iii) linear interpolation in the frequency direction for all the sub-carriers not containing any pilot signals.

Channel estimation for long term evolution (LTE) terminals

An exemplary method of communicating includes determining a first user channel estimate from a communication comprising first and second user reference sequences. The first user reference sequence is reconstructed using the determined first user channel estimate. The communication is revised based upon the reconstructed first user reference sequence. Then determining a second user channel estimate is based on the revised communication.

Iterative interference cancellation

A low complexity RACH preamble detector is described herein. The RACH preamble detection algorithm uses the peak detection of the time domain correlation function through frequency domain processing. The frequency domain processing considers the reference signals generated directly from frequency domain CAZAC sequence or time domain CAZAC sequence with DFT conversion. A low-complexity poly-phase LPF along with down sampling is implemented before the FFT to reduce the required length of the long FFT operation N-folded.

Simplified RACH preamble detection receiver

The present invention provides a method for transmitting and receiving random access channel messages in an extended range wireless communication system. One embodiment of the method may include accumulating, at a base station, signal energy received during a first portion of a transmission time interval. The method may also include accumulating, at the base station, signal energy received during a second portion of the transmission time interval. The first and second portions are offset from the start or end of the transmission time interval by selected delay intervals. The method may further include detecting the message(s) based on the signal energy accumulated during the first and second portions of the transmission time interval.

Random access channel message format for an extended range wireless communication system

There is provided a method and apparatus for reducing packet assistant channel power usage in a wireless telephone system. More specifically, there is provided a method comprising measuring a power usage for a packet assistant channel, determining whether the power usage is above a threshold, and discontinuing transmission over the packet assistant channel for a period of time if the power usage is above the threshold.

Method and apparatus for reducing packet assistant channel power usage

In a UMTS wireless communication system, the enhanced dedicated physical control channel (E-DPCCH) that is usually always transmitted together with the enhanced dedicated physical data channel (E-DPDCH) on the uplink from a UE to a NodeB is instead only transmitted when a predetermined 'start criterion' is met and is turned off when a predetermined 'stop criterion' is met until a &#x201c;start criterion&#x201d; is later met again. The UE starts transmitting E-DPCCH whenever the corresponding E-DPDCH transport format combination is different from the previous one in the same HARQ process or some other &#x201c;start criterion&#x201d; is met. Multiple mechanisms can be used to decide when the UE should switch off E-DPCCH transmission after the transport format combination of E-DPDCH has changed.

Method of increasing the capacity of enhanced data channel on uplink in a wireless communications system

A sector switch detection method incorporates two independent, concurrent switch detection processes within a sector switch detection block. A frame-based switch detection process operates over a given single period, while a sliding window-based detection system operates over a selected multiple of periods.

Sector switching detection method

In a method of canceling interference, a base station selects a known highest data rate user transmission from a received first signal containing a group of user transmissions. The known highest rate user transmission may be configured as one or more frames, each frame including a control preamble and a plurality of encoded sub-frames. The control preamble and encoded sub-frames may be decoded, and the decoded sub-frames may be used for removing interference caused by the known highest rate user transmission to all remaining transmissions of the group.

Method of interference cancellation in communication systems

In the absence of a continuous channel from the mobile terminal that incorporates a CRC in each transmitted frame from which the base station can derive a power control signal for feedback to the mobile station for maintaining the mobile station's pilot E/Nlevel at a desired target that corresponds to a particular frame error rate, the pilot signal received by the base station from the mobile terminal itself is arranged in a frame format. Each pilot frame is compared with an a prioi known transmitted pilot signal bit pattern to determine whether it has been received in error. In response to a comparison of a received pilot frame with the expected known bit pattern of the pilot frame, an error signal is derived, which in the described embodiment is either a step-up or step-down signal that is fed back to the mobile terminal to increase or decrease its transmitted pilot E/Nlevel, respectively.

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Ledgewood, NJ, United States of America

Henry Hui Ye