Nippon Telegraph and Telephone Corporation

Hitachi, Ltd.

Kazuyoshi Saito

Shinya Otsuki

Satoru Aikawa

Tomoaki Kumagai

Kengo Nagata

Atsushi Ohta

Akinori Hirukawa

Hideaki Nishiuchi

Kazuo Hiramoto

Yasuhiko Inoue

Hiroaki Sakurabata

Hiroshi Akiyama

Masahiro Tadokoro

Junichi Hirota

Takuya Nomura

Kengo Nataga

A particle beam therapy system is disclosed which includes: a synchrotron accelerating a charged particle beam injected from a pre-accelerator up to a predetermined energy level before applying a high-frequency voltage to an extraction device to extract the charged particle beam caused to exceed a stability limit; a beam transportation system transporting the charged particle beam extracted from the synchrotron up to a treatment room, and an irradiation device irradiating a patient in the treatment room with the charged particle beam in conformity to the patient's tumor shape. The synchrotron has functionality to accelerate or decelerate the charged particle beam successively to extract the charged particle beam at a plurality of energy levels during an extraction phase of the synchrotron, the beam transportation system further having functionality to block off an unnecessary charged particle beam extracted from the synchrotron during acceleration or deceleration.

Particle beam therapy system

When a transmission rate of each of lines that transmit data simultaneously between two STAs by using a plurality of radio channels and/or MIMO can be set independently, one data frame is fragmented in accordance with the transmission rates of the respective lines so as to generate a plurality of data packets having the same packet time length and data sizes equal to or smaller than a maximum data size. Those data packets are transmitted simultaneously by using a plurality of radio channels, or one radio channel and MIMO, or a plurality of radio channels and MIMO.

Wireless packet communication method

In retransmission processing due to a failure of transmission of data packets, a plurality of data packets are simultaneously transmitted between two STAs by utilizing multiple wireless channels and MIMO, and the number of idle channels and the number of retransmission packets are compared. Then, when both of the numbers are different or only when the number of idle channels is larger than the number of retransmission packets, the retransmission packets are reconstructed according to the number of idle channels, and the reconstructed retransmission packets are simultaneously transmitted by using the idle channels.

Wireless packet communication method and wireless packet communication apparatus

A charged particle beam irradiation system includes a synchrotron which accelerates an ion beam, an irradiation apparatus for irradiating an object with the ion beam introduced from the synchrotron, detection means for measuring an amount of accumulated charge of the ion beam that orbits in the synchrotron immediately before an extraction control period in an operating cycle of the synchrotron, and beam extraction control means for controlling extraction of the ion beam based on the measurement result of the accumulated beam charge amount so that extraction of a total amount of the ion beam is to be completed with an expiration of an extraction control time, the extraction control time representing a length of the extraction control period of the synchrotron and being set in advance.

Charged particle beam irradiation system and charged particle beam extraction method

A particle beam therapy system includes a synchrotron which accelerates beams of charged particles to a desired energy level and permits extraction of the beams of charged particles exceeding a stability limit, an irradiation device which irradiates an object with the beams of charged particles, a beam transport system which conducts the beams of charged particles extracted from the synchrotron to the irradiation device, and a control unit which provides control to remove part of the beams of charged particles circling in the synchrotron and allow the rest of the circling beams of charged particles to be extracted from the synchrotron and conducted to the irradiation device. The particle beam therapy system produces irradiation beams suitable for high-precision particle beam therapy by the spot scanning method or the like.

A particle beam therapy system that is capable of irradiating a target area with an irradiation beam suitable for a particle beam therapy using a spot scanning method includes a synchrotron, a beam transport system and an irradiation device. The beam transport system is provided with a beam interrupting device adapted to block supply of a charged particle beam to the irradiation device. The beam interrupting device has a beam shielding magnet, an exciting power supply for the beam shielding magnet and a beam dump. The beam transport system has a bending magnet. The beam shielding magnet is provided on an inlet side of the bending magnet. The beam dump is provided on an outlet side of the bending magnet. A controller controls the exciting power supply to control the timing of an operation of the beam shielding magnet.

It is an object of the present invention to provide a charged particle beam extraction method and particle beam irradiation system that make it possible to exercise intensity control over an extracted ion beam while a simple device configuration is employed. To accomplish the above object, there is provided a particle beam irradiation system comprising: a synchrotron for accelerating and extracting an charged particle beam; an irradiation apparatus for extracting the charged particle beam that is extracted from the synchrotron; first beam intensity modulation means for controlling the beam intensity of the charged particle beam extracted from the synchrotron during an extraction control period of an operation cycle of the synchrotron; and second beam intensity modulation means for controlling the beam intensity during each of a plurality of irradiation periods contained in the extraction control period of the operation cycle.

Particle beam irradiation system

Data packets are transmitted between two STAs capable of using plural radio channels and MIMO together, by using idle channels and MIMO. When at least one idle channel has been detected, plural data packets are generated in the same number as the sum of MIMO numbers of the respective idle channels, in which the data packets are generated from one or plural data frames, and plural data packets having the same packet time length are transmitted simultaneously between the two STAs by using the idle channels and MIMO.

A particle beam therapy system using a spot scanning method includes a synchrotron, a beam transport system, an irradiation system, and a controller. A controller is configured to turn on a radio frequency electromagnetic field to be applied to an extraction system when a charged particle beam is to be supplied to the irradiation system, and turn off the radio frequency electromagnetic field to be applied to the extraction system when the supply of the charged particle beam to the irradiation system is to be blocked by means of an electromagnet provided in the beam transport system or in the synchrotron. The controller is also adapted to turn off a radio frequency acceleration voltage to be applied to an acceleration cavity in synchronization with the turning-off of the radio frequency electromagnetic field to be applied to the extraction device.

A plurality of types of available transmission rates to be used for transmission of data packets are individually managed for each receiver terminal. When there are a plurality of data packets to be transmitted onto a transmission buffer and when it is possible to transmit said plurality of data packets simultaneously, the packet sizes representative of the data amounts of the respective data packets are referred to as well as the transmission rates of the respective data packets associated with the receiver terminals. The packet time lengths (transmission times) defined by the packet sizes and transmission rates are checked for the respective data packets. A plurality of data packets whose packet time lengths are approximately equal to each other are selected regardless of their receiver terminals. The transmissions of the plurality of selected data packets are commenced simultaneously by use of a plurality of radio channels.

For data packet transmission in special format generated by connecting or patching data frames, a request packet and reply packet receivable only by STAs supporting the special format are transmitted/received before the data packet transmission, to check and manage the STA supporting the special format. Based on management information in own station, the data packet is transmitted in the special or standard format according to a receive-side STA. For generating plural data packets in special format in which plural data frames are patched, the plural data frames having subheaders added are connected and divided to data blocks. A main header including information necessary to restore patched data frames are added to each data block, and a control information field and a frame check field of a data packet are added before and after the data block having the main header added thereto, respectively, to generate data packets.

Wireless packet communication method and apparatus

A transmit-side STA transmits a wireless packet using a wireless channel which has been determined to be idle by both a physical carrier sense for determining based on received power whether the wireless channel is busy or idle and a virtual carrier sense for determining the wireless channel to be busy during set transmission inhibition time. At this time, the transmit-side STA sets transmission time used for the virtual carrier sense to a paired wireless channel which is affected by leakage from a transmitting wireless channel. This allows for setting transmission inhibition time to a paired wireless channel even when the paired wireless channel cannot successfully receive due to the effect caused by leakage from the transmitting wireless channel.

Growing community of inventors

Tokyo, Japan

Kazuyoshi Saito