NTT DoCoMo

About: NTT DoCoMo is a based out in . It is known for research contribution in the topics: Base station & Mobile station. The organization has 4032 authors who have published 8655 publications receiving 160533 citations.

System, method and computer program product for content/context sensitive scanning utilizing a mobile communication device

Abstract: A system, method and computer program product are provided for scanning application program data utilizing a mobile communication device. Included is an application program installed on a mobile communication device capable of communicating via a wireless network. Such application program is adapted for performing tasks utilizing the mobile communication device. Associated therewith is a scanning subsystem in communication with the application program for scanning application data relating to the tasks performed by the application program. In use, the application program communicates information relating to the application data to the scanning subsystem to facilitate the scanning by the scanning subsystem.

CDMA demodulator and demodulation method

Abstract: A CDMA demodulator which can follow fast fading, and reduce interference components from other users in the same cell. A received input spread signal is despread by an orthogonal filer (103). The orthogonal filer provides the input spread signal with successive delays each of an amount of 1/m of the chip interval of a spreading code, multiplies the delayed signals by tap coefficients, and sums up the products, thereby outputting the despread signal. Pilot symbols in the despread signal are compared with known pattern pilot symbols by an absolute phase estimator/phase error compensator (107) to obtain phase fluctuations of the received pilot symbols. The phase fluctuations are interpolated to each information symbol, and each information symbol is phase compensated. The phase compensated information symbols are decided by a decision block (108). The tap coefficients are calculated by a tap coefficient controller (110) so that the mean square error of differences between signals before and after the decision is kept minimum, and the calculated values are fed back to the orthogonal filter.

On the Throughput Capacity of Opportunistic Multicasting with Erasure Codes

Abstract: In this paper, we concentrate on opportunistic scheduling for multicast information. We pose the problem as a multicast throughput optimization problem. As a solution we present how one can jointly utilize fixed-rate and rateless erasure coding along with simple rate adaptation techniques in order to achieve the optimal multicast throughput per user. We first investigate the performance of the proposed system under i.i.d. channel conditions. Our analysis shows a linear gain for the multicast capacity over i.i.d. Rayleigh fading channels with respect to the number of users. Since the established results require coding over large number of blocks and hence induce large decoding delays, we extend our analysis to the cases where we code over shorter block lengths and thus quantify the delay-capacity tradeoffs under a simple setting. We further look into non-i.i.d. channel conditions and show achievable gains by modifying a scheduling heuristic whose fairness is well- established for opportunistic scheduling of unicast flows. Our overall evaluations demonstrate that under both i.i.d. and non-i.i.d. channel conditions, opportunistic multicasting with erasure coding can significantly improve the performance over the traditional techniques used in today's communication systems.

Base station, radio resource control equipment, mobile station, communication system, and communication method

Abstract: A base station includes: an acquisition unit for acquiring a quantity of stored packets from a mobile station, the quantity of stored packets being stored in a buffer for storing the packets transmitted by the mobile station; a radio resource controller for allocating priority radio resources preferentially usable by the mobile station to a radio channel for the mobile station, and for allocating usable radio resources allowed to be used by the mobile station from the priority radio resources to the mobile station by use of the quantity of stored packets acquired by the acquisition unit; and a result notification unit for reporting a result of the allocation by the radio resource controller to the mobile station

Location information providing apparatus, communication terminal, mobile communication terminal and location information providing method

Abstract: A positional information service server selects a measuring system most suitable for measuring quality conditions received from a terminal requesting measurement when able to measure position of a designated mobile unit to be measured by a plurality of measuring systems. The positional information service server acquires the positional information of the mobile unit based on the selected measuring system, and transmits it to the terminal designated as the one to be notified.