摘要:
In a wireless multi-hop network, a transmission scheduling apparatus calculates a transmission demand of every node within the wireless multi-hop network, and allocates a time slot to each node by using the transmission demand of each node.
摘要:
The apparatus includes a data normalization unit, a neural network problem prediction unit, and a transition change prediction unit. The data normalization unit creates normalization transformation values by performing normalization transformation based on threshold value ranges for a plurality of pieces of vehicle network data. The neural network problem prediction unit creates a neural network problem prediction value by predicting a mixed problem with the vehicle using a multi-artificial neural network model, created based on a learning data set related to mixed problems having previously occurred in the vehicle and the normalization transformation values. The transition change prediction unit predicts a change in transition for the mixed problem according to a change in the neural network problem prediction value, by analyzing the neural network problem prediction value and previous neural network problem prediction values previously created in the vehicle.
摘要:
A first roadside equipment operates as a transmitting/receiving mode in a control channel interval of an Nth synchronization interval so as to support a handover. In this instance, a second roadside equipment neighboring to the first roadside equipment operates as a receiving mode in the control channel interval of the Nth synchronization interval. The first roadside equipment operates as the receiving mode in a control channel interval of an (N+1)th synchronization interval. In this instance, the second roadside equipment operates as the transmitting/receiving mode in the control channel interval of the (N+1)th synchronization interval.
摘要:
Disclosed is a method for increasing a data transfer rate without an increase in the whole bandwidth using intrinsic spreading codes and orthogonal codes. The method uses interleaving, OFDM modulation/demodulation, and maximum likelihood detection (MLD) to overcome the effects of multipath fading or signal interference, determines grouped optimal values by a grouping method of dividing the intrinsic spreading codes in series, and calculates an integrated optimal value for all the intrinsic spreading codes using the grouped optimal values, thereby reducing the complexity of MLD according to the length of the intrinsic spreading code and acquiring an improved performance.
摘要:
A device for allocating a channel by using wireless access in a vehicular environment in which an onboard unit is provided in a vehicle and at least one roadside unit is provided, receives a service announcement message from at least one roadside unit, uses the service announcement message to generate an available service table, determines whether the available service table has roadside unit entries for transmitting the service announcement message, and if so, compares average RSSI provided by the roadside units to select a roadside unit to access, selects a channel that corresponds to the service provider ID with the highest priority from among the service provided by the selected roadside unit, and assigns the selected channel as a service channel to exchange information with the roadside unit.
摘要:
An automatic gain control method of a receiving apparatus is provided. The automatic gain control method includes low-noise amplifying a signal using a first gain value, amplifying the low-noise amplified signal to a second gain value, determining the first gain value using a strength of the low-noise amplified signal, and determining the second gain value using the signal amplified to the second gain value. Accordingly, the reliability of the automatic gain control may be guaranteed.
摘要:
A diversity transmitting/receiving apparatus and method is provided, which is implemented using space-time trellis codes (STTC) constructed from a Pseudo Noise (PN) sequence set in a Direct Sequence (DS) CDMA system. The transmitter comprises a PN sequence generator, a space-time encoder, first and second modulators, and first and second multiple transmit antennas. The space-time encoder selects two of the multiple PN sequences to construct STTC, and space-time encodes data from a data source according to the STTC to output an Wary data symbol. The two modulators modulate the space-time encoded data according to the STTC. The two multiple transmit antennas wirelessly transmit outputs of the two modulators, respectively. By applying a method using space-time coding in a DS CDMA system including multiple transmit antennas, it is possible to achieve both diversity and additional coding gain and also to reduce multiple user interference by increasing the PN sequence length.
摘要:
A cooperative communication method for vehicular communication is provided. The method in which when one vehicle transmits a signal to another vehicle, a signal of a transmission vehicle passes through a roadside device or a plurality of vehicles and thereafter signals having a plurality of paths are transmitted to a reception vehicle, and the reception vehicle combines and demodulates the signals received through the plurality of paths.
摘要:
Provided are a method and apparatus for performing a variable point Inverse Fast Fourier Transform (IFFT)/Fast Fourier Transform (FFT). The apparatus for performing a variable point IFFT includes: an IFFT interpolator generating interpolation data signals having a determined point and interpolating a plurality of interpolation data, the number of which depends on an IFFT operation mode signal into input data; an IFFT operator generating IFFT operation data signals by performing an IFFT operation for the interpolated data signals; an IFFT mode selector selecting and outputting some of the IFFT operation data signals in response to the IFFT operation mode signal so that the selected IFFT operation data have the same number of points as the input data; and a control unit outputting the IFFT operation. Therefore, it is possible to easily compute variably sized IFFT/FFT hardware.
摘要:
Disclosed are a base station and a mobile terminal for location detection, and a location detecting method. The base station in which a plurality of antennas having RF modules are installed transmits a signal including location information of each of the antennas to the mobile terminal. The mobile terminal carries out location detection by selectively using location information received from a GPS receiver or location information received from a DSRC transceiver. The base station and mobile terminal for location detection can perform location detection with high accuracy using the existing DSRC service. Thus, the base station and mobile terminal can carry out location detection having an error of approximately 10 m in downtown areas or buildings.