摘要:
A handover control apparatus selects, as a target station, an adjacent station having an upturn and stable transition trend of reception level of a radio wave received by a radio, when necessity to carry out handover is determined, and performs handover for switching from a serving station to the target station when the transition trend of the reception level of the received radio wave from the serving station is in a downturn trend and a calculation value of a serving station approximation equation is smaller than a calculation value of an adjacent station approximation equation at a determination timing.
摘要:
A handover control apparatus selects, as a target station, an adjacent station having an upturn and stable transition trend of reception level of a radio wave received by a radio, when necessity to carry out handover is determined, and performs handover for switching from a serving station to the target station when the transition trend of the reception level of the received radio wave from the serving station is in a downturn trend and a calculation value of a serving station approximation equation is smaller than a calculation value of an adjacent station approximation equation at a determination timing.
摘要:
In a handover control apparatus, a terminal is wirelessly connected with one of base stations to establish a wireless data communications connection. The terminal executes a handover process using a handover process section when an electric wave state becomes lower than a threshold value, which is variable. The threshold value can be adjusted according to a moving speed of the terminal. Furthermore, the threshold value is corrected according to the past electric wave state. The threshold value is corrected according to a difference of (i) a minimum electric wave state in a preceding handover process, and (ii) a lower limit. The correction is executed so as to reduce an excessive decline of an electric wave state in a succeeding handover process. Deterioration of a communications quality during a handover process can be thereby suppressed.
摘要:
In a handover control apparatus, a terminal is wirelessly connected with one of base stations to establish a wireless data communications connection. The terminal executes a handover process using a handover process section when an electric wave state becomes lower than a threshold value, which is variable. The threshold value can be adjusted according to a moving speed of the terminal. Furthermore, the threshold value is corrected according to the past electric wave state. The threshold value is corrected according to a difference of (i) a minimum electric wave state in a preceding handover process, and (ii) a lower limit. The correction is executed so as to reduce an excessive decline of an electric wave state in a succeeding handover process. Deterioration of a communications quality during a handover process can be thereby suppressed.
摘要:
It is determined whether each of several subcarriers has an adequate propagation characteristic in a first horizontally polarized wave antenna. Of the several subcarriers, a subcarrier, which is determined to have an adequate propagation characteristic in the first horizontally polarized wave antenna, is assigned with transmission data. A transmission signal containing the transmission data is thereby transmitted from the first horizontally polarized wave antenna. In addition, of the several subcarriers, a subcarrier, which is determined not to have an adequate propagation characteristic in the first horizontally polarized wave antenna, is also assigned with transmission data in either a second horizontally polarized wave antenna or a vertically polarized, wave antenna. A transmission signal containing the transmission data is thus transmitted from the second horizontally polarized wave antenna or the vertically polarized wave antenna.
摘要:
A planar antenna is disclosed. The planar antenna includes: a radiator element having a wideband resonant characteristic; and a parasitic element having a planar shape. The parasitic element has a first side, a second side, a third side and a fourth side. Each of the first side and the second side is parallel to a direction of an electric current to be excited in the radiator element. The first side is located closer to the radiator element than the second side is. The first side is shorter than the second side. The third side connects one ends of the first side and the second side. The fourth side connects the other ends of the first side and the second side. A region between the third and fourth sides tapers in a direction from the second side toward the first side.
摘要:
An on-board communication equipment on each of two vehicles receives a radio wave from two or more GPS satellites, and determines a carrier wave phase of the received radio wave. Then, the on-board communication equipment on one vehicle receives, from the other vehicle, information on the carrier wave phase observed in the other vehicle. Further, the on-board communication equipment calculates a relative position of a self vehicle relative to the other vehicle by a Carrier-Phase DGPS positioning based on a difference between two carrier wave phases (e.g., single difference, double difference or the like), that is, one from the self vehicle and one from the other vehicle, both having the same observation time, from among the available carrier wave phases.
摘要:
A vehicle device for use in vehicle-roadside communication that communicates with a roadside device disposed on a roadside includes a radio unit for receiving an informational message from the roadside device as well as a display and a speaker for information provision. The vehicle device further includes a storage unit for storing the informational message received by the radio unit. A system controller in the vehicle device determines whether information provision condition for providing the informational message in the storage unit is met based on an information content and current condition information in the informational message received by the radio unit. When the information provision condition is determined to be met, the system controller controls the display and the speaker to cause a provision of the informational message.
摘要:
A PDC/PHS phone has both PDC communication function and PHS communication function. The PDC/PHS phone switches its communication mode from a PDC communication to a PHS communication which is less power consuming than the PDC communication, when its built-in battery runs down to a reference level in the course of communication with another phone. The PDC/PHS phone switches its communication mode back to the PDC communication again, when the battery is recharged enough.
摘要:
An in-vehicle antenna device includes: a dielectric element having a front surface, first and second side surfaces and a rear surface and including a power supply point on both the first and second side surfaces, a first conductive surface on the first side surface, a second conductive surface on the second side surface, and a third conductive surface on the rear surface; and an antenna element including a base element coupled with the power supply point at one corner of the front surface and a branch element connected to the base element and having an end. A part of the branch element moves apart from one of the first and second conductive surfaces as it goes from the base element to the one end of the branch element. The front surface is attached to a windshield of a vehicle.