公开(公告)号：JPH03171931A

公开(公告)日：1991-07-25

申请号：JP30935189

申请日：1989-11-30

Applicant: TOSHIBA CORP

Inventor： NOUTO KATSUYA ,  SAKAKIBARA KATSUMI

IPC: H04B7/212 ,  H04B7/26 ,  H04L12/28

Abstract: PURPOSE:To prevent the collision of an idle/busy signal by sending out a data signal in which a preamble signal is introduced only when no transmission inhibiting signal is incorporated in a read signal. CONSTITUTION:A communication equipment 25 and plural base stations 1-3 are connected by a transmission line 7, plural base stations 1-3 and plural mobile stations 4, 5 are connected by a bidirectional radio channel, respectively, and communication is executed between the communication equipment 25 and plural mobile stations 4, 5 by the bidirectional radio channel through the base stations 1-3. Also, plural mobile stations 4, 5 are provided with a means for transmissing a transmission requesting signal to the base stations 1-3, respectively, and plural base stations 1-3 transmit a transmission permitting signal until a transmission requesting signal is received, respectively. Moreover, when the transmission requesting signal is received, a transmission inhibiting signal for inhibiting the transmission of other mobile stations 5 (4) than the mobile stations 4 (5) corresponding to this transmission requesting signal is transmitted only during the time allocated to its own station in time zones brought to multiplex time division of plural base stations 1-3, respectively. In such a manner, even if the base stations 1-3 generate different busy/idle signals, the collision of the busy/idle signal can be prevented.

公开(公告)号：JPH02132933A

公开(公告)日：1990-05-22

申请号：JP28562188

申请日：1988-11-14

Applicant: TOSHIBA CORP

Inventor： SAKAKIBARA KATSUMI

IPC: H04J3/00 ,  H04B7/212 ,  H04L7/00 ,  H04L12/40

Abstract: PURPOSE:To improve collision frequency, and in addition, to reduce mean transmission delay time by providing a base station with a collision detecting means, an ACK signal generating means and a collision counting means, and providing a slave station with a receiving means and a time slot setting means, etc. CONSTITUTION:For a transmission line in which plural pieces unit of time slots time-divided at equal intervals constitutes a frame, plural slave stations 1 send information in synchronism with the time slot selected at random. In this case, the base station 2 detects collision by the collision detecting part 15, and the number of the collided time slots is counted by the collision counting part 17 through the ACK signal generating part 16, and is sent to the stations 1 together with an ACK signal by a transmitting part 18. Each of the stations 1 receives the signal of the station 2 by the receiving part 7, and reduces the number of the time slot through the time slot setting part 10 according as counted result increases, and in addition, in the case of the collision of the information its own station transmitted, it makes this information synchronize with the time slot set by the part 10 at random, and transmits it. Thus, the collision frequency can be improved, and simultaneously, the means transmission delay time can be reduced.

公开(公告)号：JPH03280610A

公开(公告)日：1991-12-11

申请号：JP8190490

申请日：1990-03-28

Applicant: TOSHIBA CORP

Inventor： YOSHIDA HIROSHI ,  SERIZAWA MUTSUMI ,  SAKAKIBARA KATSUMI ,  OGURA KOJI

IPC: H03G3/30

Abstract: PURPOSE:To limit the amplitude of a reception signal within a stable range and to input the limited signal to an equalizer by calculating power of a training signal, retarding a burst signal for a processing time of power calculation or over, and correcting the amplitude of an output signal of a delay means based on the result of calculation. CONSTITUTION:The control circuit is provided with a power calculation means 3 receiving a burst signal comprising a training signal and a data signal to calculate the power of the training signal and a delay means 1 receiving the burst signal, and retarding the burst signal for a processing time or over required for the power calculation means 3. Moreover, an amplitude control means 5 is provided, which corrects the amplitude of an output signal of the delay means 1 based on the power obtained from the power calculation means 3 and a prescribed power to bring the amplitude of the training signal within a prescribed range. Then the training signal is used to control the amplitude in the burst signal by the feed forward method and the training signal especially important in the burst signal is controlled to an ideal value. Thus, excellent amplitude control is implemented.

公开(公告)号：JPH03244220A

公开(公告)日：1991-10-31

申请号：JP4171490

申请日：1990-02-22

Applicant: TOSHIBA CORP

Inventor： SAKAKIBARA KATSUMI ,  SERIZAWA MUTSUMI ,  OGURA KOJI

IPC: H04B3/06

Abstract: PURPOSE:To attain equalizing control corresponding to the environment of a multipath by providing an automatic symbol interval equalizer part, automatic time interval equalizer part and equalizing output switching means and switching an equalizing output to any one of the outputs of the both automatic equalizer parts. CONSTITUTION:For example, when a reception station is distant from a transmission station and a multipath delay time is made long, a switch control part 104 is set to the side of an automatic symbol interval equalizer part 101 (namely, an L side). When the reception station is near the transmission station and the multipath delay time is short, the switch control part 104 controls the switch 103 so as to be set on the side of an automatic time interval equalizer part 102. Thus, since the output signals of the above mentioned automatic equalizers 101 and 102 are switched corresponding to the environment of the multipath, the equalizing control is enabled corresponding to the environment of the multipath. Further, even when the control is made corresponding to the multipath at minute intervals, the amount of tap coefficient calculation can be suppressed small each time the tap coefficient is updated.

公开(公告)号：JPH03177136A

公开(公告)日：1991-08-01

申请号：JP31706589

申请日：1989-12-06

Applicant: TOSHIBA CORP

Inventor： NAMEKATA MINORU ,  OGURA KOJI ,  SERIZAWA MUTSUMI ,  SAKAKIBARA KATSUMI

IPC: H04L27/01 ,  H03H17/00 ,  H04B3/04 ,  H04B3/06

Abstract: PURPOSE:To shorten the measuring time of a code error rate to be used as a threshold by calculating the rates of discordance of the codes of the outputs of a first and a second demodulating means, and selecting a demodulated signal on the basis of this result. CONSTITUTION:A code comparator 106 measures the rate D of dicordance between the code of the output from the first demodulating part 102 and the code of the output from the second demodulating part 104 for a predetermined period. Then, the code comparator 106 compares this discordance rate D with the predetermined discordance rate Dc, and if D>Dc, it decides that the code error rate of the output of the first demodulating part 102 is better than the code error rate of the output of the second demodulating part 104, and selects the output of the first demodulating part 102. On the other hand, if D

公开(公告)号：JPH03154435A

公开(公告)日：1991-07-02

申请号：JP29223589

申请日：1989-11-13

Applicant: TOSHIBA CORP

Inventor： SERIZAWA MUTSUMI ,  SAKAKIBARA KATSUMI ,  OGURA KOJI

IPC: H04B3/10 ,  H04L25/03

Abstract: PURPOSE:To obtain excellent equalizing performance by increasing a feedforward tap number of a decision feedback equalizer when information set precedingly from a training signal in one burst more that the number when the information sent later than the training signal. CONSTITUTION:When the information sent precedingly from a training signal in one burst is obtained, the feedforward tap number of a decision feedback equalizer 23 is increased more than a tap number when the information sent later than the training signal is obtained. Moreover, the feedback tap number of the decision feedback equalizer 23 when the information sent later than the training signal is obtained is increased more than the tap number when the information set before the training signal. Thus, the tap number is increased without changing a tap coefficient revision circuit 14 and the transmission line tracking characteristic is not degrated to improve the performance of the equalizer.

公开(公告)号：JPH0385026A

公开(公告)日：1991-04-10

申请号：JP22121089

申请日：1989-08-28

Applicant: TOSHIBA CORP

Inventor： SAKAKIBARA KATSUMI ,  SERIZAWA MUTSUMI

IPC: H04B3/10

Abstract: PURPOSE:To improve the reliability by judging whether or not a transmission line distortion exceeds the equalizing capability of an adaptive automatic equalizer, and equalizing a data signal only when the distortion does not exceed, thereby preventing the equalizer from giving for itself distortion further onto the data signal. CONSTITUTION:A mean value measuring section 23 measures a mean value of an equalizing error signal e(t) for a predetermined period within a training period. Then a comparator section 24 compares a measured mean value with a predetermined threshold level. Then whether or not a transmission line distortion exceeds the equalizing capability of an equalizer is discriminated momentarily at the end of the training period. When a mean value is larger than the threshold level, that is, the transmission line distortion exceeds the equalizing capability of the equalizer, a data signal in succession to the training signal is outputted as it is from an output terminal out without being equalized by the changeover of a changeover switch 21.

公开(公告)号：JPH02288625A

公开(公告)日：1990-11-28

申请号：JP11059589

申请日：1989-04-28

Applicant: TOSHIBA CORP

Inventor： SAKAKIBARA KATSUMI

IPC: H04B7/26

Abstract: PURPOSE:To reduce the line occupancy time due to retransmission and to improve the line operating efficiency by decreasing the length of a signal to be sent when a data sent from a terminal station collides with a signal from other terminal station or an error takes place during the transmission, and the terminal station sends the data newly. CONSTITUTION:A control station 1 supervises whether or not a preamble signal is detected from an incoming line 3 while sending an idle signal to an outgoing line 4, and when th preamble signal is detected from the incoming line 3, a busy signal is sent to the outgoing line 4. When the station 1 receives at least an ID signal, the signal instincts a terminal station 2 which made transmission to send the remaining signal not yet received and the terminal station 2 receiving the instruction places the preamble signal to send only the remaining signal. Thus, the time occupied by the line due to the retransmission is reduced and the line utilizing efficiency is improved.

公开(公告)号：JPH01289341A

公开(公告)日：1989-11-21

申请号：JP11830388

申请日：1988-05-17

Applicant: TOSHIBA CORP

Inventor： SAKAKIBARA KATSUMI ,  NAKAMURA MAKOTO

IPC: H04L1/18

Abstract: PURPOSE:To improve the transmission efficiency and to reduce the probability of dead lock state at the sender side by sending a new data packet of a number corresponding to the difference between data packet number and retransmission packet number constituting one frame in succession to the retransmission packet. CONSTITUTION:A transmission station 1 has a means constituting a prescribed number of data packets as one frame and sending new data packets of a number corresponding to a difference between the retransmission packet number and the data packet number constituting one frame in succession to the retransmission packet. A reception station 2 has a means identifying whether a series of reception signals from the transmission station is the retransmission packet or the new data packet and a means correcting an error included in one frame packet sent by the retransmission packet obtained by the identification means. Thus, number of data packets is increased substantially without increasing the data length of the data packet. Thus, the communication transmission efficiency is improve and the probability of being in dead lock at the sender station side is reduced.

公开(公告)号：JPH01238241A

公开(公告)日：1989-09-22

申请号：JP6356288

申请日：1988-03-18

Applicant: TOSHIBA CORP

Inventor： SAKAKIBARA KATSUMI

IPC: H04L1/16

Abstract: PURPOSE:To recover error information within a short time while keeping high circuit utilization efficiency by providing a transmission part which transmits an information signal corresponding with an order section shown by a signal which shows two orders transmitted from a reception station to a transmission station. CONSTITUTION:When tenth data I(10) is received by the reception station 2 at (ts) o'clock, for example, a sequence error is detected 22 and the retransmission demand instruction (Prej) (7 and 9) of the data I(7)-I(9) of the transmission order numbers 7-9 are generated by a retransmission demand instruction generation part 24 and transmitted from a transmission part 25 to the transmission station 1. Then, when the instructions (Prej) (7 and 9) are received by the transmission station 1 at (t11) o'clock, the seventh to ninth data I(7)-I(9) is read from a memory 13 by the transmission part 14 and preferentially retransmitted. On the other hand, when the reception station 2 receives the retransmitted data I(7)-I(9) until (t12) o'clock, it substitutes the order of the data I(10) and I(11) and successively outputs the data I(7)-I(11) from the reception station 2.