Ntt Docomo, Inc.

The University of Texas System

Hlaing Minn

Fujio Watanabe

Chia-Chin Chong

Hiroshi Inamura

Amin Khansefid

A multi-input multi-output rotating frequency division duplexing transceiver in non-contiguous bands comprising an adaptive duplex filter, a controller coupled to the adaptive duplex filter, wherein an uplink band and a downlink band are rotated before each transmission sub-frame, and wherein at least two of the bands are non-contiguous, a multi-output adaptive frequency synthesizer coupled to the controller, a transmit mixer coupled to the adaptive duplex filter and to the multi-output adaptive frequency synthesizer and a receive mixer coupled to the adaptive duplex filter and to the multi-output adaptive frequency synthesizer.

Spectrum-agile multiple input multiple output system and capacity adaptation between uplink and downlink

A non-cyclic evolving-type user resource structure applicable for use in the uplink and the downlink of an OFDMA system with large null guard tones (e.g., a 3GPP LTE system) is provided. In one example, the user resource structure combines the benefits of localized and distributed types of resource structures available in the current baseline 3GPP LTE (Release 8) specifications, and is especially suitable for operating in a fast time-varying channel. In another example, the non-cyclic evolving-type resource structure may be simplified to have no more than three stages: a band-type first stage, a partially evolved-type second stage and an interleaved-type third stage. Depending upon the target or average mobile speed and packet length, the resource structure may even have less than three stages.

Non-cyclic evolving-type user resource structure for OFDMA based system with null guard tones

An evolving-type resource structure supports high data rate services at high mobile speeds. The evolving-type resource structure is an efficient diversity-exploiting user resource structure for fast time-varying frequency-selective fading channel environments. In one example, an evolving-type resource structure takes advantages of both band-type and interleaved-type structures which exploit both multiuser diversity and frequency diversity in fast time-varying channels. The evolving-type resource structure is applicable to centralized, semi-distributed and distributed access schemes and may be used in both downlink (DL) and uplink (UL) transmissions in a cellular system.

Evolving-type user resource structure/channelization with enhanced diversity for OFDMA based time-varying channels

A mobile communication system uses a multiple-input-multiple-output (MIMO) technology with an orthogonal frequency division multiplexing access (OFDMA) scheme. At network entry, an initial ranging method selects from multiple ranging signal designs to accomplish the initial ranging process. Three classes of ranging signal designs may be selected for use in generating ranging codes. The information on the ranging signal design to be used, which is selected by the base station based on the cell size of the communication system (i.e., the radio coverage area of the base station), is broadcast from the BS. The ranging signal designs are directly applicable to single-antenna systems, and they are applied to MIMO systems by using appropriate mapping across transmit antennas based on the adopted MIMO ranging transmission scheme. Optimum eigenmode and suboptimum eigenmode transmission schemes provide the best performance at high computational complexity and high power consumption.

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Allen, TX, United States of America

Hlaing Minn