PILOT USE OF SPREAD-SPECTRUM MULTIPLE ACCESS SYSTEM BASED UPON ORTHOGONAL FREQUENCY-DIVISION MULTIPLEXING

    公开(公告)号:JP2001358695A

    公开(公告)日:2001-12-26

    申请号:JP2001119083

    申请日:2001-04-18

    Abstract: PROBLEM TO BE SOLVED: To solve the connectional problems by regarding the pilot tones of a generated pilot tone hopping sequence as multiple pilot tones and without transmitting any of them, each time the frequency range of the generated pilot tone hopping sequence exceeds the usable bandwidth of a specific system. SOLUTION: Base station discrimination and downlink synchronization are actualized, by using a pilot including known symbols transmitted with specific frequency tone at individual specific time intervals. More specifically, the symbols used for the pilot are arranged characteristically in time-frequency grids having positions specified by a periodical pilot tone hopping sequence. In a specific embodiment, cycles of the pilot tone hopping sequence start with a Latin-square based hopping sequence, and are discharged for a certain time and constituted by sequentially changing the offset and order possibly over frequencies. A specific example of the pilot tone hopping sequence is a parallel slope hopping sequence selected, so that the periodicity of the sequence is a prime number of symbol time intervals.

    SUPPORT OF LINK LEVEL OF WIRELESS DATA

    公开(公告)号:JP2002027539A

    公开(公告)日:2002-01-25

    申请号:JP2001184192

    申请日:2001-06-19

    Abstract: PROBLEM TO BE SOLVED: To deal with transmission of access request and transmission of paging of a mobile station and a base station in a wireless communication system by transmitting and detecting both the access request from the mobile station and the paging from the base station by using an efficient uniform method. SOLUTION: The mobile station monitors access requests and specified resources and detects whether paging is received. Upon detection of an access request, a corresponding request message is generated and is substantially immediately transmitted to the base station. In this way, the latency of access process is minimized. At the same time, the base station monitors for determining whether paging directions are received and determines whether an access request message is received by monitoring the specified resources. In this process, processing of request messages is given priority to processing of paging. Upon detection of the received request message, a request responding message is generated and is substantially immediately transmitted to the mobile station. In this way, the latency of access process is minimized.

    DEVICE FOR ACQUIRING UPLINK TRAFFIC CHANNEL IN RADIO COMMUNICATION SYSTEM AND METHOD FOR THE SAME

    公开(公告)号:JP2002125271A

    公开(公告)日:2002-04-26

    申请号:JP2001246862

    申请日:2001-08-16

    Abstract: PROBLEM TO BE SOLVED: To provide uplink traffic channel allocation using an exclusive control channel capable of ensuring the designated parts of a control channel resource for transferring uplink traffic channel requests. SOLUTION: A response to an uplink traffic channel request 1 transmitted from a traveling object device 202-1 in a group G1 is transmitted from a base station 201 between time slots S2 and S3, and received between time slots S4 and S5. The traveling object device 201-1 retransmits an uplink traffic channel request 1 in a group G2 without waiting for this response from the base station 201. Next, the traveling object device 202-1 receives the response from the base station 201. Then, the traveling object device 202-1 is able to transmit an uplink traffic channel request 2 in a group 3.

    UPLINK TIMING SYNCHRONIZATION AND ACCESS CONTROL FOR MULTI-ACCESS WIRELESS COMMUNICATION SYSTEM

    公开(公告)号:JP2001257641A

    公开(公告)日:2001-09-21

    申请号:JP2001033039

    申请日:2001-02-09

    Abstract: PROBLEM TO BE SOLVED: To provide a technology to realize uplink timing synchronization and access control with respect to a wireless communication system in general especially in a multi-access wireless communication system. SOLUTION: A mobile station of this invention transmits a general-purpose uplink access signal at any of intervals. When this access is permitted, a base station transmits access confirmation including initial timing and power correction together with designation of an initial channel at which the mobile station can start call setup process. For re-synchronization, the mobile station transmits a timing synchronizing signal in exclusive timing and at an access interval. The base station measures the arrival time of the signal and returns proper timing correction. Thus, the orthogonality between mobile stations can surely be maintained.

    METHOD FOR USE IN BASE STATION/WIRELESS TERMINAL TRANSMITTING PAGING MESSAGE IN WIRELESS COMMUNICATION SYSTEMS

    公开(公告)号:JP2002223470A

    公开(公告)日:2002-08-09

    申请号:JP2002001694

    申请日:2002-01-08

    Abstract: PROBLEM TO BE SOLVED: To provide an apparatus and method for use between a wireless terminal and a base station transmitting a paging message in wireless communi cation systems. SOLUTION: In a unique paging time slot format, each of the allocated paging time slots occurs periodically and is split into several prescribed paging time slots including at least one first type slot having a relatively short duration and at least one second type paging time slot having a longer duration. The first type paging time slots is of relatively short duration and indicates whether a particular associated wireless terminal was paged. The second type paging time slots is of longer duration than the first type time slot and transports the entire paging message.

    METHOD FOR USE IN WIRELESS MULTIPLE ACCESS CONNECTION COMMUNICATION SYSTEM

    公开(公告)号:JP2002204204A

    公开(公告)日:2002-07-19

    申请号:JP2001336716

    申请日:2001-11-01

    Abstract: PROBLEM TO BE SOLVED: To efficiently support multicasting in a wireless system. SOLUTION: In a wireless communication system, a multicast message is transported to a group of wireless terminals by using a common control channel so that a multicast paging message showing that multicast traffic data are sent to the specific group of the wireless terminals is sent. In this example, essential information transmitted in the common control channel is the identifier of the group of wireless terminals intended to receive the multicast traffic data and the location of a traffic channel by which multicast traffic should be transported among channel resources and the channel resources can include the representation of band width and a time interval. When a side view of this invention is taken, the common control channel is related to the traffic channel by a specific fixed method.

    WIRELESS MULTIPLE ACCESS COMMUNICATION SYSTEM, AND DEVICE USED IN TRANSMITER AND RECEIVER THEREOF

    公开(公告)号:JP2002094486A

    公开(公告)日:2002-03-29

    申请号:JP2001219076

    申请日:2001-07-19

    Abstract: PROBLEM TO BE SOLVED: To provide an efficient wireless multiple access communication system. SOLUTION: This device used for the transmitter of a wireless multiple access communication system is provided with an error-detecting encoder, to which the input array of information bits is applied for generating the array of error detection redundant bits, and for generating first block bits, having the prescribed number of bits by adding the array of the error detection redundant bits to the array of information bits; a mapper, to which input block bits having the prescribed number of bits and a user index are applied, based on the first block bits for generating second block bits which have a prescribed number of bits according to the input block bits and the prescribed function of the user index; and a modulator for modulating a transmission signal, based on the second block bits for transmitting it to a user receiver.

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