Abstract:
In a wireless communication system for communicating with a plurality of stations at the same point of time with the same frequency using a Space Division Multiple Access (SDMA), wireless resources are allocated by a first decision unit which evaluates performance of each station obtained when the SDMA is used and which determines periods of time to be allocated to groups of stations formed according to the SDMA technique. Using a first evaluation unit and a second evaluation unit to evaluate performance required by each station and each application, the first decision unit allocates the wireless resources to the stations. It is therefore possible that the wireless resources are efficiently allocated to the stations while preventing an event in which the wireless resources are excessive or insufficient for required quality of service.
Abstract:
Transmission power relative to a propagation path having a variation in gain is controlled to increase communication channel capacity, and a data rate is controlled in accordance with the variation of the increased communication channel capacity. In order to increase the communication channel capacity, the transmission power is determined so that the sum of noise power (=received noise power/propagation path gain) converted into one at a transmitter and the transmission power becomes constant. As a result, contrary to the background art, the transmission power is controlled to be reduced when the propagation path gain decreases and to be increased when the propagation path gain increases.
Abstract:
A radio communication system having a base station and a plurality of radio terminals, wherein each radio terminal having a transmission request transmits a reservation packet at arbitrary timing through a reservation channel in accordance with a CDMA scheme, and the base station assigns a traffic channel and a time slot to be used to each radio terminal requesting a reservation through a reply packet outputted onto a reply channel. On the reservation channel, a short spreading code corresponding to a matched filter is applied.
Abstract:
A communication quality is improved or signal processing is simplified in a multi-carrier communication system such as OFDM. Information different in communication quality such as systematic bits and parity bits of turbo encoded code words is combined together, and information that requires a high communication quality such as the systematic bits is mapped to carriers having a frequency close to the carriers in which the pilot signal exists used as a reference phase of demodulation than the information such as the parity bits which does not require the high communication quality such as the systematic bits.
Abstract:
An image processing apparatus includes a displaying unit, a movement specifying unit, and a moving unit. The displaying unit displays a preview including a data image corresponding to data input thereto and at least one of a function image corresponding to a selected function and a print-area image corresponding to a print area within which the data is to be printed. The movement specifying unit specifies, in response to an input to move any image in the preview, a distance and a direction based on which the image is to be moved. The moving unit moves the image by the distance in the direction to rearrange layout of the preview.
Abstract:
A method, system, and apparatus are provided for detecting a position of a terminal in a network accurately without a GPS receiver. In one example, a method for locating a position of a terminal includes calculating a position of a base station; detecting a clock time difference between the base station and another base station; measuring a reception timing of a signal received by the base station from the terminal; and locating the position of the terminal using at least the position of the base station, the clock time difference, and the reception timing.
Abstract:
A method, system, and apparatus are provided for detecting a position of a terminal in a network accurately without a GPS receiver. In one example, a method for locating a position of a terminal includes calculating a position of a base station; detecting a clock time difference between the base station and another base station; measuring a reception timing of a signal received by the base station from the terminal; and locating the position of the terminal using at least the position of the base station, the clock time difference, and the reception timing.
Abstract:
An image forming apparatus of the present invention intends to reduce a difference of usage frequency among a plurality of sheet feeding section and comprises: a plurality of sheet feeding section capable of feeding different types of sheets; a printer main body for forming an image on a sheet fed by the sheet feeding section; an accumulation counter for counting the accumulation quantity of fed sheets of each of the plural sheet feeding section; and a controller for determining bias of usage frequency of each sheet feeding section based on a counting result of the accumulation counter and changing the allocation of the sheets of each sheet feeding section to reduce the bias of the usage frequency of each sheet feeding section.
Abstract:
A method and apparatus for controlling the power of a signal transmitted between a base station and a mobile terminal which constitute a mobile communication system. At least one of the base station and the mobile terminal has functions to compare a predetermined reference value and a necessary transmission power obtained as a result of transmission power control in order to compensate for a signal intensity fluctuation occurring on a link between the base station and the mobile terminal, temporarily stopping the transmission if the necessary transmission power is larger than a predetermined permissible value, and transmit the signal if the necessary transmission power is equal to or smaller than the predetermined permissible value.
Abstract:
In a mobile communication system, the tracking of synchronization is conducted in a stable state even in a multipath environment. A delay profile detector calculates a delay profile a(n) using a despread signal for each processing unit n. A delay profile averaging unit averages a(n) to produce Ave(|a(n)|2). A data symbol detector conducts rake combining of the despread signal using a(n) and Ave(|a(n)|2). According to a(n) and Ave(|a(n)|2, a weighting function unit calculates a representative value representing delay waves. A loop filter generates a control signal in response to the representative value. A clock controller controls a spread code generator according to the control signal.