Abstract:
Provided are a high-speed Discrete Fourier Transform (DFT) apparatus and a method thereof. The high-speed DFT apparatus includes a zero padding unit, a Fast Fourier Transform (FFT) unit, and a preamble index decision unit. The zero padding unit receives a first input signal having a length of a prime number and changes the first input signal into a second input signal having a length of an exponentiation of 2. The FFT unit performs a FFT on the second input signal outputted from the zero padding unit. The preamble index decision unit detects a preamble index from an output signal from the FFT unit.
Abstract:
Disclosed are an apparatus and a method for managing radio resources, capable of effectively managing radio resources. When a normal call and a handover call are attempted, radio resources are allocated and it is determined whether or not to perform an overload control based on received load related information and then it is determined whether or not to admit the call depending on an availability of a bandwidth for radio resources, a priority of real time traffic or a locking probability of data. The quality and efficiency of a mobile communication service is enhanced by pertaining an effective allocation on radio resources and controlling the load of radio resources in the mobile communication system. The radio resource managing apparatus and method using the same are applied to IMT (International Mobile Telecommunications)-Advanced system base station, thereby optimizing the efficiency of radio resources.
Abstract:
Disclosed are a method and apparatus for allowing a Software Defined Radio (SDR) terminal to perform a vertical handover between different services. The vertical handover method includes: receiving a handover request from an application service which is currently being executed; selecting a new application service which is a handover target from among a plurality of application services, in response to the handover request; installing the new application service in the SDR terminal so that the new application service is executable by the SDR terminal; and performing a handover to the new application service. Accordingly, since handover is performed seamlessly between different services, continuity of service may be ensured.
Abstract:
A handover determination apparatus and method in an overlay wireless network environment is provided. A handover situation is detected with consideration of a user environment including user requirements and service efficiency, as well as received signal strength of a wireless network, and an unnecessary handover due to a temporary condition change is prevented by use of a dwell timer. Accordingly, a seamless optimized wireless network service can be provided to a user regardless of a location of the user.
Abstract:
The present invention relates to a method of transmitting data in a handover between base stations. When a mobile terminal performs a handover between base stations in a wireless communication system, a gateway transmits data traffic to be transmitted to a mobile terminal by using an IGMP (Internet Group Management Protocol) to a serving base station being serviced to the mobile terminal and a target base station to which a handover of the mobile terminal is made in a bi-casting method. Accordingly, when the mobile terminal performs the handover between the base stations, the gateway transmits the data traffic in the bi-casting method. As a result, it is possible to efficiently use a resource of a user plane connection interval between the gateway and the base station, thereby minimizing the loss of data traffic transmitted in a downlink, that is, data.
Abstract:
The present invention relates to a QoS information controller in a multi-cell environment and a method thereof. According to an exemplary embodiment of the present invention, the QoS information controller is used in the multi-cell environment to determine the traffic characteristic, the mobile communication system characteristic, the traffic processing capacity, and the radio resource, and to control the QoS information. In addition, a QoS requested by a user may be achieved since the traffic characteristic, the mobile communication system characteristic, the traffic processing capacity, and the radio resource are determined and the QoS information is controlled to efficiently process the QoS information for the multimedia traffic in the multi-cell environment.
Abstract:
Disclosed is a call admission controlling device and method for providing QoS (quality of service) in the portable Internet. When a mobile terminal requests a guarantee of the corresponding QoS and a call admission, a packet access router calculates a bandwidth available for resource reservation according to mobility characteristics of a cell to which the mobile terminal belongs, and determines resource reserved states according to the mobility characteristics with adjacent cells based on the calculated bandwidth to thus control call admission in order to satisfy a handoff dropping probability of the corresponding cell and prevent disconnected calls when a handoff toward the adjacent cells occurs. As a result, the handoff dropping probability of cells is guaranteed, and the resources are utilized effectively.
Abstract:
Provided is a base station. The base station includes a transceiver, a frequency allocation unit, and an orthogonal code allocation unit. The transceiver communicates with a terminal. The frequency allocation unit allocates a frequency resource to the terminal through the transceiver. The orthogonal code allocation unit generates an orthogonal code index table including a plurality of orthogonal code combinations, and allocates one of the orthogonal code combinations included in the orthogonal code index table to each terminal, to which the frequency resource has been allocated for a service request of the terminal, through the transceiver not to multiply be allocated. At least one of a plurality of orthogonal codes included in the orthogonal code combination is orthogonal to at least one of a plurality of orthogonal codes included in an orthogonal code combination allocated to another terminal.
Abstract:
A wireless access router for separately controlling a traffic signal and a control signal is provided. In a mobile communication access network structure, in order to optimally support a mobile communication terminal, a control signal and a traffic signal of a base station are divided, and a router is controlled by mobile communication system functions such as a mobility management function, a QoS management function, a session control of the terminal, a mobility control, and a QoS control function that are effectively processed. With a wireless access router having the divided control signal and traffic signal, it is expected the traffic concentration and a packet transmission delay can be prevented.
Abstract:
Provided is a subframe scheduling method in which a relay may transmit interval information of a service to a base station, and the base station may modify a location of a subframe based on the interval information, and thereby preventing a quality deterioration occurring due to a retransmission failure. The subframe scheduling method may include: setting and transmitting, by a base station, subframe information; setting and implementing, by a relay, a service based on the subframe information; transmitting, by the relay, interval information of the service to the base station; modifying, by the base station, the subframe information based on the interval information; and transmitting, by the base station, the modified subframe information to the relay.