JP6085177B2 - Wireless terminal device - Google Patents

Description

  The present invention relates to a wireless terminal device.

  In a wireless communication method called LTE (Long Term Evolution), which is being standardized by 3GPP (3rd Generation Partnership Project), as a multiple access method, OFDMA (Orthogonal) is used as a line (downlink) in a direction from a base station to a terminal. An SC-FDMA (Single Carrier Frequency Division Multiple Access) system is used for a line (uplink) in a direction from the terminal to the base station. As for the transmission speed, it is possible to realize a maximum of about 300 Mbps in the downlink and a maximum of about 75 Mbps in the uplink using a band of 1.4 MHz to 20 MHz.

  Then, for the purpose of further improving frequency utilization efficiency and peak data rate, a successor system called LTE Advanced (LTE-Advanced) has been studied. The LTE advanced system employs CA (Carrier aggregation) that uses a plurality of bandwidth component carriers (CCs) that can be used by the LTE system simultaneously.

  Further, a wireless communication system exemplified in FIG. 3 has been studied (see, for example, Non-Patent Document 1). In the wireless communication system of FIG. 3, a wireless terminal device 300 performs simultaneous communication with a plurality of wireless base station devices 100 and 200 installed at different locations using different frequencies f0 and f1.

NTT DoCoMo, RWS-120010, “Requirements, Candidate Solutions & Technology Roadmap for LTE Rel-12 Onward”, 3GPP Workshop on Release 12 and onwards, June 2012

  In the wireless communication system illustrated in FIG. 3 described above, a problem is a method of reporting the state of the transmission buffer of the wireless terminal device 300 to the wireless base station devices 100 and 200. The transmission buffer of the wireless terminal device 300 stores a packet to be transmitted to the wireless base station device 100 and a packet to be transmitted to the wireless base station device 200. When reporting the amount of packets stored in this transmission buffer to both radio base station apparatuses 100 and 200, each radio base station apparatus 100 and 200 reports a packet quantity different from the packet quantity actually transmitted to itself. There is a possibility that.

  The present invention has been made in view of such circumstances, and in a wireless communication system using a plurality of CCs, a transmission buffer of a wireless terminal device that communicates simultaneously with a wireless base station device using a plurality of CCs is provided. It is an object of the present invention to provide a wireless terminal device capable of efficiently reporting a state to a wireless base station device.

  In order to solve the above-described problem, a radio terminal apparatus according to the present invention is transmitted for each radio base station apparatus in a radio terminal apparatus that communicates simultaneously with the radio base station apparatus using a plurality of frequency bands. A buffer state report creating unit for creating a buffer state report for reporting a scheduled packet amount is provided.

  In the radio terminal apparatus according to the present invention, a transmission buffer is provided for each radio base station apparatus, and a buffer status report corresponding to each radio base station apparatus is accumulated in the transmission buffer corresponding to each radio base station apparatus. It indicates the amount of packets that are present.

  In the wireless terminal device according to the present invention, a common transmission buffer is provided in each of the wireless base station devices, and a buffer status report creation unit corresponding to each of the wireless base station devices is accumulated in the common transmission buffer, The packet quantity corresponding to each of the radio base station apparatuses is indicated.

  According to the present invention, in a wireless communication system using a plurality of CCs, the state of a transmission buffer of a wireless terminal device communicating simultaneously with the wireless base station device using a plurality of CCs is efficiently reported to the wireless base station device. The effect that it can do is acquired.

It is a schematic block diagram of the radio | wireless terminal apparatus 1 which concerns on 1st Embodiment of this invention. It is a schematic block diagram of the radio | wireless terminal apparatus 2 which concerns on 2nd Embodiment of this invention. It is a schematic block diagram which shows an example of a radio | wireless communications system.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, LTE and LTE Advanced will be described as an example of a wireless communication method.

[First Embodiment]
FIG. 1 is a schematic configuration diagram of a wireless terminal device 1 according to the first embodiment of the present invention. In FIG. 1, the wireless terminal device 1 includes a packet distribution unit 11, a buffer unit 12, a wireless packet distribution unit 13, and a buffer status report creation unit 14.

  The wireless terminal device 1 can communicate simultaneously with the wireless base station device using a plurality of CCs. The buffer unit 12 is provided corresponding to the radio base station apparatus. Only one buffer unit 12 or a plurality of buffer units 12 may be provided for one radio base station apparatus. When one radio base station apparatus can use a plurality of CCs, the buffer unit 12 may be provided corresponding to a set of the radio base station apparatus and the CC.

  The packet distribution unit 11 outputs a packet received from an upper layer (not shown) to one of the buffer units 12 according to a predetermined distribution rule. Examples (1) to (4) of the distribution rule are shown below.

(1) The packet is distributed to a predetermined buffer unit 12 by distinguishing whether the packet is a control plane (C-Plane: Control-Plane) or a user plane (U-Plane: User-Plane).

(2) The packet is distributed to a predetermined buffer unit 12 according to the QoS requested by the bearer service to which the packet belongs.

(3) The packets are adaptively distributed to any of the buffer units 12 according to the amount of packets (packet size) remaining in each buffer unit 12.

(4) The packet is adaptively allocated to one of the buffer units 12 according to the radio channel quality of the radio layer. For example, the packets are distributed so that the packets are distributed according to the communication speed for each radio channel achieved by the radio channel quality of the radio layer.

  The packet distribution unit 11 may use one distribution rule or a combination of a plurality of distribution rules.

  The buffer unit 12 stores the packet received from the packet distribution unit 11. The buffer unit 12 generates a radio packet from a packet held by itself according to a scheduling instruction received from a scheduler (not shown), and outputs the radio packet to the radio packet sorting unit 13. The buffer unit 12 outputs the buffer status information A indicating its own buffer status to the buffer status report creation unit 14. The buffer status information A includes information indicating the amount of packets accumulated in the buffer unit 12.

  The radio packet sorting unit 13 outputs the radio packet received from the buffer unit 12 to a lower layer (not shown) corresponding to the destination radio base station device.

  The buffer status report creation unit 14 creates a buffer status report (BSR) using the buffer status information A received from each buffer unit 12. A BSR is created for each radio base station apparatus. When one radio base station apparatus can use a plurality of CCs, a BSR may be created for each set of radio base station apparatus and CC.

  The buffer status report creation unit 14 creates a BSR indicating the packet amount indicated by the buffer status information A. When a plurality of buffer units 12 correspond to one radio base station apparatus, the buffer status report creating unit 14 creates a BSR using the BSRs of the plurality of buffer units 12. The buffer status report creation unit 14 outputs the created BSR to a lower layer (not shown) corresponding to the destination radio base station apparatus.

[Second Embodiment]
FIG. 2 is a schematic configuration diagram of the wireless terminal device 2 according to the second embodiment of the present invention. In FIG. 2, the wireless terminal device 2 includes a packet distribution unit 21, a buffer unit 22, a wireless packet distribution unit 23, and a buffer status report creation unit 24. The wireless terminal device 2 can communicate simultaneously with the wireless base station device using a plurality of CCs. The buffer unit 22 is provided in common to each radio base station apparatus.

  The packet distribution unit 21 outputs a packet received from an upper layer (not shown) to the buffer unit 22.

  The buffer unit 22 stores the packet received from the packet distribution unit 21. The buffer unit 22 generates a radio packet from a packet held by itself according to a scheduling instruction received from a scheduler (not shown), and outputs the radio packet to the radio packet distribution unit 23. The buffer unit 22 outputs the buffer status information C indicating its own buffer status to the buffer status report creation unit 24. The buffer status information C includes information indicating the amount of packets accumulated in the buffer unit 22.

  The radio packet sorting unit 23 outputs the radio packet received from the buffer unit 22 to a lower layer (not shown) corresponding to any destination radio base station device according to a predetermined sorting rule. Examples (1) to (3) of the distribution rules are shown below.

(1) Distinguish whether the original packet of the radio packet is from the control plane, and distribute the radio packet to a lower layer corresponding to the radio base station apparatus of a predetermined destination.

(2) The wireless packet is distributed to a lower layer corresponding to a predetermined destination wireless base station apparatus according to the QoS requested by the bearer service to which the original packet belongs.

(3) According to the radio channel quality of the radio layer, radio packets are adaptively distributed to lower layers corresponding to any destination radio base station apparatus in units of original packets. For example, the packets are distributed so that the packets are distributed according to the communication speed for each radio channel achieved by the radio channel quality of the radio layer.

  The buffer status report creation unit 24 creates a BSR using the buffer status information C received from the buffer unit 22. A BSR is created for each radio base station apparatus. When one radio base station apparatus can use a plurality of CCs, a BSR may be created for each set of radio base station apparatus and CC.

  The buffer status report creation unit 24 creates a BSR using the buffer status information C according to a predetermined BSR creation method. Examples (1) to (4) of the BSR creation method are shown below.

(1) A BSR indicating the amount of packets is created for each plane by distinguishing between control plane packets and user plane packets. In this case, the buffer status information C includes information indicating the packet amount of the control plane and the packet amount of the user plane.

(2) A BSR indicating the packet amount is created for each QoS requested by the bearer service to which the packet belongs. In this case, the buffer status information C includes information indicating the packet amount of each QoS.

(3) Assume that a packet is adaptively distributed to any destination radio base station apparatus according to the radio channel quality of the radio layer, and a BSR indicating the packet amount is created for each destination radio base station apparatus. For example, packet distribution is performed so that packets are distributed according to the communication speed for each radio channel achieved with the radio channel quality of the radio layer.

  The BSR creation method used by the buffer status report creation unit 24 corresponds to the sorting rule used by the wireless packet sorting unit 23.

  The buffer status report creation unit 14 outputs the created BSR to a lower layer (not shown) corresponding to the destination radio base station apparatus.

  According to the embodiment described above, a BSR corresponding to each radio base station apparatus can be created. Thereby, in a wireless communication system using a plurality of CCs, the state of the transmission buffer of the wireless terminal device that communicates simultaneously with the wireless base station device using the plurality of CCs can be efficiently reported to the wireless base station device. The effect of being able to be obtained is obtained.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.

  In the above-described embodiment, LTE is exemplified as an example of a wireless communication method, but the present invention can be similarly applied to other wireless communication methods.

DESCRIPTION OF SYMBOLS 1,2 ... Wireless terminal device, 11, 21 ... Packet distribution part, 12, 22 ... Buffer part, 13, 23 ... Wireless packet distribution part, 14, 24 ... Buffer status report preparation part

Claims (3)

In a wireless terminal device that communicates simultaneously with a wireless base station device using a plurality of frequency bands,
A buffer status report creating unit that creates a buffer status report for reporting the amount of packets scheduled to be transmitted for each radio base station device ,
A transmission buffer is provided for each radio base station device,
Wherein each of the radio base stations corresponding buffer status report to the system, shows the amount of packets accumulated in the transmission buffer corresponding to each radio base station apparatus,
A packet distribution unit that distinguishes packets received from higher layers according to whether they are control plane packets or user plane packets and distributes them to the predetermined transmission buffer;
Wireless terminal device. In a wireless terminal device that communicates simultaneously with a wireless base station device using a plurality of frequency bands,
A buffer status report creating unit that creates a buffer status report for reporting the amount of packets scheduled to be transmitted for each radio base station device ,
A transmission buffer is provided for each radio base station device,
Wherein each of the radio base stations corresponding buffer status report to the system, shows the amount of packets accumulated in the transmission buffer corresponding to each radio base station apparatus,
A packet distribution unit that adaptively distributes and outputs packets received from an upper layer to any of the transmission buffers according to the amount of packets remaining in each of the transmission buffers,
Wireless terminal device. In a wireless terminal device that communicates simultaneously with a wireless base station device using a plurality of frequency bands,
A buffer status report creating unit that creates a buffer status report for reporting the amount of packets scheduled to be transmitted for each radio base station device ,
A transmission buffer is provided for each radio base station device,
Wherein each of the radio base stations corresponding buffer status report to the system, shows the amount of packets accumulated in the transmission buffer corresponding to each radio base station apparatus,
A packet distribution unit that adaptively distributes and outputs the packet received from the upper layer to any of the transmission buffers according to the radio channel quality of the radio layer;
Wireless terminal device.

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