WO2001015375A1 - Systeme de capture de trame, procede de capture de trame, et recepteur - Google Patents

Systeme de capture de trame, procede de capture de trame, et recepteur Download PDF

Info

Publication number
WO2001015375A1
WO2001015375A1 PCT/JP1999/004576 JP9904576W WO0115375A1 WO 2001015375 A1 WO2001015375 A1 WO 2001015375A1 JP 9904576 W JP9904576 W JP 9904576W WO 0115375 A1 WO0115375 A1 WO 0115375A1
Authority
WO
WIPO (PCT)
Prior art keywords
synchronization
burst
frame
synchronous
channel
Prior art date
Application number
PCT/JP1999/004576
Other languages
English (en)
Japanese (ja)
Inventor
Yasuyuki Nagashima
Original Assignee
Mitsubishi Denki Kabushiki Kaisha
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Denki Kabushiki Kaisha filed Critical Mitsubishi Denki Kabushiki Kaisha
Priority to PCT/JP1999/004576 priority Critical patent/WO2001015375A1/fr
Publication of WO2001015375A1 publication Critical patent/WO2001015375A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L7/00—Arrangements for synchronising receiver with transmitter
    • H04L7/04—Speed or phase control by synchronisation signals
    • H04L7/10—Arrangements for initial synchronisation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J3/00—Time-division multiplex systems
    • H04J3/02—Details
    • H04J3/06—Synchronising arrangements
    • H04J3/0602—Systems characterised by the synchronising information used
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L7/00—Arrangements for synchronising receiver with transmitter
    • H04L7/04—Speed or phase control by synchronisation signals
    • H04L7/08—Speed or phase control by synchronisation signals the synchronisation signals recurring cyclically

Definitions

  • the present invention relates to capturing a frame by a synchronous burst while data communication is continued by a communication burst.
  • this relates to frame capture such as inter-satellite diversity and inter-satellite handover when multiple satellites are used in medium / low-orbit mobile satellite communications.
  • the mobile satellite communication system that uses satellites with medium or low orbit has a distinctive feature that, unlike geostationary satellites, the satellites appear to move significantly. For this reason, the mobile satellite communication system uses satellite selection (inter-satellite diversity), or satellite switching (inter-satellite handover), or a combination of hygiene selection and hygiene switching to obtain optimal reception quality. Is required.
  • FIG. 7 is a block diagram showing an example of a function provided in the receiver 10P for performing conventional synchronization and timing control.
  • 101 is a received modulated wave received
  • 102 is a demodulated signal obtained by demodulating the received modulated wave 101
  • 103 is received information extracted from the demodulated signal 102
  • Reference numeral 04 denotes a synchronization word detection signal for notifying that a synchronization word has been detected from the demodulated signal 102
  • reference numeral 105 denotes reception information from the demodulated signal 102.
  • a timing instruction signal for instructing a timing for extracting a broadcast portion 106 is a demodulation timing instruction signal for instructing a demodulation timing, 107 is a synchronous mode detection timing signal for instructing a synchronous mode detection timing, 1 08 is a reception channel control timing signal for instructing the timing for controlling the reception channel, and 109 is a reception channel instruction signal for instructing the reception channel.
  • Reference numeral 1 denotes a demodulation unit that demodulates the received modulation wave 101
  • 2 denotes a reception information extraction unit that analyzes the demodulation signal 102 and extracts reception information 103
  • 3 denotes a demodulation signal.
  • 4 is a synchronous timing controller that controls the synchronization state of the frame and the timing of each processing
  • 5 is a receive channel controller that controls the channel to receive. And specifically controls a burst type, a reception frequency, and the like.
  • Demodulation section 1 receives received modulated wave 101, demodulates received modulated wave 101, and outputs demodulated signal 102.
  • the output demodulated signal 102 is input to a reception information extraction unit 2 and a synchronization word detection unit 3.
  • the synchronization mode detection unit 3 detects a synchronization word from the demodulation signal 102 based on the synchronization mode detection timing signal 107 output by the synchronization timing control unit 4.
  • the synchronization word detection unit 3 outputs a synchronization mode detection signal 104 indicating detection or non-detection of a synchronization mode based on the result of detecting the synchronization word.
  • Synchronous mode detection signal 104
  • the timing controller 4 is based on the synchronization word detection signal 104.
  • Reception information extracting section 2 outputs reception information 103 based on demodulated signal 102 and timing instruction signal 105.
  • Fig. 8 shows an example of the configuration of a conventional synchronous burst.
  • 21 P is a synchronization burst composed of a group of data for synchronization
  • 23 is a synchronization mode composed of a bit sequence having strong autocorrelation.
  • the synchronization word 23 is located at the center of the synchronization burst 21 P.
  • the synchronization word 23 may be located at the beginning of the burst or immediately after the preamble serving as delimiter information (synchronization code). is there.
  • the receiver 10P detects the synchronization code 23 included in the synchronization burst 21P by the synchronization word detection unit 3 and the synchronization / timing control unit 4, and estimates the timing of each processing (hereinafter, referred to as “synchronization burst”).
  • Control processing ”).
  • Fig. 9 shows an example of the flow of synchronization control involving switching satellites during communication.
  • 21 Y and 21 Z are synchronization bursts
  • 23 ⁇ and 23 3 are synchronization words.
  • 31X is the communication burst of satellite X
  • 32 is the data reception processing for demodulating the communication burst and extracting the received information in the receiver
  • 33 is the reception of the synchronization burst in the receiver 10 1.
  • synchronization control processing The arrow t indicates the flow of time.
  • the range indicated by a frame using an arrow is equivalent to one satellite frame.
  • One frame of satellite Y or satellite Z is not shown, but the range represented in the same manner corresponds to one frame.
  • synchronization of frame timing between satellites is maintained. At this time, synchronization of frame timing is performed with reference to the satellite.
  • the ground station such as mobile satellite communication is not always located at a fixed position, for example, even if the frame timing is kept synchronized on the satellite, the ground station does not always have the frame timing. Synchronization is not maintained, and may be out of sync as in the example in Figure 9. In such a case, as shown in the example of the satellite Z in the figure, the timing of the communication burst 31X and the timing of the synchronization code 23Z may overlap, and the synchronization word 23Z may not be received.
  • FIG. 10 is a block diagram showing an example of a burst generation function provided in a conventional transmitter 70P.
  • the transmitter 70P corresponds to, for example, a base station that enables communication of a mobile terminal.
  • the example of FIG. 10 shows an example in which three different frequency channels are used.
  • 71 A to 71 C are synchronization burst placement circuits for instructing the transmission timing of the synchronization burst
  • 72 A to 72 C are the communication bursts for instructing the transmission timing of the communication burst.
  • 73A to 73C are synchronous burst placement circuits that generate synchronous bursts in accordance with 71A to 71C
  • 74A to 74C are communication burst placement circuits.
  • This is a communication burst generation circuit that generates a communication burst.
  • the transmitter 70P generates a synchronization burst or a communication burst for each channel.
  • 75 A is a channel X processing section that arranges and generates a synchronization burst or communication burst for channel X.
  • 75B is a processing section for channel Y
  • 75C is a processing section for channel Z.
  • the processing unit 75A for channel X performs the following processing.
  • the transmission timing of the synchronous burst is determined by the synchronous burst arrangement circuit 71A.
  • the synchronous burst generation circuit 73A generates a synchronous burst and transmits the generated synchronous burst.
  • the communication burst arrangement circuit 72A determines the transmission timing of the communication burst.
  • the communication burst generation circuit 74A transmits the communication burst according to the determined transmission timing.
  • channel X The same processing as for channel X is performed for channel Y and channel ⁇ . These are generally assigned different frequencies, and although the frame timing of each channel is synchronized for processing convenience, transmission is basically performed at an independent timing for each channel.
  • the frame was captured in the manner described above. As a result, a synchronization burst in which the receiver cannot receive the synchronization word occurs, which increases the reception interval of the synchronization command and slows down the following of the ever-changing frame timing. there were.
  • the present invention has been made to solve such a problem, and has as its object to smoothly capture a frame even while continuing data communication. Disclosure of the invention
  • a frame capturing method is a frame capturing method for capturing a frame using a synchronization burst including a synchronization code for synchronizing the frame.
  • a receiver that captures the frame using a synchronous burst including a plurality of synchronous codes.
  • the plurality of synchronization codes are characterized by a plurality of synchronization codes each having a small cross-correlation.
  • the plurality of synchronization codes are arranged at different positions of the synchronization burst, and the receiver captures a frame using one synchronization word of the plurality of synchronization codes.
  • the above-described frame capturing method further uses a plurality of channels including a synchronization channel for transmitting a synchronization burst including a synchronization word and a communication channel for transmitting a communication burst including data to be communicated,
  • the receiver receives data by a communication burst transmitted by the communication channel, and captures a frame of the synchronization channel by a synchronization burst transmitted by the synchronization channel. .
  • the receiver captures a frame of a synchronization channel having a frequency different from the frequency of the communication channel.
  • the plurality of channels are a plurality of channels having different frequencies, and the receiver captures frames of a plurality of synchronization channels having different frequencies.
  • the receiver is
  • a plurality of synchronization word detectors for detecting a plurality of synchronization codes of the received synchronization burst and outputting a plurality of synchronization word detection signals; and a plurality of synchronization code detections output by the plurality of synchronization word detection units.
  • a plurality of synchronization timing control units for outputting a plurality of timing control signals for controlling timing for extracting information to be received from the synchronization burst based on each of the signals;
  • a selecting unit for selecting one synchronization timing control signal from the plurality of synchronization timing control signals output by the plurality of synchronization timing control units.
  • the receiver is
  • a plurality of synchronization code detection units for detecting a plurality of synchronization words of the received synchronization burst and outputting a plurality of synchronization code detection signals; and a plurality of synchronization code detection units output by the plurality of synchronization code detection units.
  • a selector for selecting one synchronous code detection signal from the output signal;
  • a synchronization timing control unit for outputting a timing control signal for controlling a timing of extracting information received from the synchronization burst based on the synchronization code detection signal output by the selection unit.
  • a frame capturing method includes a transmitter for transmitting a synchronization burst for synchronizing a frame, and a receiver for receiving the synchronization burst.
  • the transmitter transmits a communication burst including data to be communicated.
  • a plurality of channels including a communication channel for transmitting and a communication channel having a different frequency from the communication channel and transmitting a synchronization burst for synchronization are used.
  • the receiver Transmitting a synchronization burst to the synchronization channel during a period in which the communication burst is not transmitted to the communication channel;
  • the receiver receives the communication burst transmitted from the transmitter, receives the synchronization burst transmitted from the transmitter, and captures the frame of the synchronization channel by the received synchronization burst.
  • the transmitter transmits a plurality of synchronization bursts to a plurality of synchronization channels having different frequencies
  • the receiver receives the plurality of synchronization bursts, and captures frames of a plurality of synchronization channels having different frequencies.
  • the transmitter notifies the receiver in advance of a period for transmitting the synchronous burst, transmits the synchronous burst in the previously notified period,
  • the receiver receives the synchronization burst in the previously notified period, and captures the frame of the synchronization channel by the received synchronization burst.
  • the transmitter includes a frame counter that indicates a period for transmitting a synchronization burst of each of the plurality of channels.
  • the frame acquisition method is characterized in that it is used in a low or medium orbit mobile satellite communication system.
  • a frame capturing method includes a step of capturing a frame using a synchronization burst including a plurality of synchronization codes for synchronizing the frame.
  • the frame capturing method transmits a synchronization burst having a frequency different from that of the communication channel and taking synchronization during a period in which the communication burst is not transmitted to a communication channel transmitting a communication burst including data to be communicated.
  • a receiver according to the present invention is a receiver for capturing a frame using a synchronization burst including a synchronization code for synchronizing the frame.
  • a plurality of synchronization code detectors for respectively detecting the plurality of synchronization words using a synchronization burst including a plurality of synchronization words.
  • FIG. 1 is a diagram showing an example of synchronization control in the frame capturing method and method according to the first embodiment of the present invention.
  • FIG. 2 is a diagram illustrating an example of a configuration of the synchronization burst according to the first embodiment of the present invention.
  • FIG. 3 is a block diagram showing an example of a function for performing synchronization and timing control provided in the receiver according to the first embodiment of the present invention.
  • FIG. 4 is a block diagram showing an example of a function for performing synchronization and timing control provided in the receiver according to Embodiment 2 of the present invention.
  • FIG. 5 is a block diagram showing an example of a configuration for controlling the timing of transmitting a synchronous burst provided in the transmitter according to the third embodiment of the present invention.
  • FIG. 6 is a diagram showing an example of an arrangement of a communication burst and a synchronous burst according to the third embodiment of the present invention.
  • FIG. 7 is a block diagram showing an example of a conventional function for performing synchronization and timing control.
  • FIG. 8 is a diagram showing an example of a configuration of a conventional synchronous burst.
  • Figure 9 shows an example of conventional synchronous control with satellite switching during communication.
  • FIG. 10 is a block diagram showing an example of a configuration for controlling timing for transmitting a synchronous burst provided in a conventional transmitter.
  • a transmitter for transmitting data transmits a synchronization burst including a plurality of synchronization words
  • a receiver for receiving data receives the synchronization burst including the above-described synchronization words and transmits a frame. Capture.
  • the frame synchronization state refers to a state in which frame timing is grasped and signals (data) can be transmitted and received.
  • Frame capture refers to an operation from a state where a frame synchronization state is not established to a state where a frame synchronization state is established. That is, the frame capture indicates an operation until the frame timing is grasped.
  • frame capture is sometimes referred to as "capture frame”.
  • synchronizing frames is synonymous with capturing frames.
  • the establishment of the frame synchronization state indicates a state in which the frame capturing operation has been completed.
  • Maintaining frame synchronization or maintaining frame synchronization refers to maintaining the frame synchronization state after the frame synchronization state is established. Therefore, the state where the frame synchronization is maintained corresponds to the frame synchronization state.
  • Figure 1 shows the situation in which frame capture is performed smoothly by showing the flow of time-series processing for each satellite. Details will be described later.
  • FIG. 2 is a diagram showing an example of the configuration of a synchronization burst taken as an example in this embodiment.
  • 21 and 23 are the same as FIG. 24 and 25 are different synchronization words each having a different pattern from 23.
  • the synchronization word 24 and the synchronization word 25 need to be at least different from the synchronization word 23.
  • the cross-correlation with sync word 23 is as low as possible, and even between sync word 24 and sync word 25, the cross-correlation is as low as possible. desirable.
  • FIG. 2 shows an example of the synchronization burst 21, and the synchronization word may not necessarily be arranged as shown in FIG. Synchronous codes may be arranged continuously, but the problem of erroneous detection remains.
  • FIG. 3 is a block diagram illustrating an example of a function provided in the receiver for performing synchronization and timing control. Those with the same reference numerals are the same as in FIG.
  • 104a to 104c are synchronization word detection signals.
  • 110a to 110c are timing control signals for controlling timing.
  • the 3A to 3C are the same as the sync word detector 3 in FIG. 7, and are sync word detectors for detecting any one of the sync words 23 to 25, respectively.
  • the synchronization word detection unit 3 is provided corresponding to the number of synchronization codes included in the synchronization burst 21. Each sync code detection The units 3A to 3C detect a predetermined one of a plurality of synchronization words 23 to 25.
  • a synchronization / timing control unit that controls the synchronization state of the frame and the timing of each processing based on the timing.
  • timing instruction signal 1 is a timing instruction signal 1 based on a predetermined standard among a plurality of timing control signals 110a to 110c detected by the synchronization / timing control units 4A to 4C. It is a selection unit to select as 05. Next, the operation of the receiver 10 will be described.
  • the basic operation of the receiver 10 in FIG. 3 is the same as the operation of the conventional receiver 10 P described with reference to FIG. 7, and a description thereof will be omitted.
  • the difference from the conventional technology is that the operation of the synchronization timing control units 4A to 4C is performed for each of the synchronization codes 23 to 25 from the operation of the synchronization word detection units 3A to 3C. And the processing of the selection unit 6 has been added, and will be described below.
  • the sync word detectors 3A to 3C detect the sync word from the demodulated signal 102, as in the conventional technology, and detect or not detect a signal, or, if necessary, a detection signal including a detection timing. Output as sync code detection signals 104a to 104c.
  • Timing control units 4A to 4C perform necessary synchronization state control using the synchronization code detection signals 104a to 104c, respectively, and control the timing of each processing. Outputs 110a to 110c respectively.
  • the selecting unit 6 is configured to select the most appropriate one of the timing control signals 110a to 110c output by the respective synchronization timing control circuits 4A to 4C based on a predetermined reference. An appropriate one is selected as the timing instruction signal 105.
  • the predetermined criterion is, for example, when the detection of the synchronization word is detected by correlation with the pattern of the synchronization word, the timing output from the timing control unit 4A to 4C corresponding to the synchronization code having the highest correlation value. Select the control signal.
  • FIG. 1 shows a time series of a synchronous control processing flow according to the frame capturing method and method of the present invention.
  • 21Y and 21 1 are synchronous bursts
  • 23 ⁇ to 25 ⁇ and 23 3 to 25 ⁇ are synchronous codes.
  • 31X is a communication bus for communicating data arranged in a frame
  • 32 is a data reception process for demodulating a communication burst in a receiver and extracting received information
  • 33 is a receiver.
  • 2 shows a synchronization control process for receiving a synchronization burst, capturing a frame, maintaining frame synchronization, and estimating the timing of each process.
  • the arrow and the range corresponding to one frame are the same as in the description of FIG.
  • a channel for transmitting a transmitter burst is a communication channel
  • a channel for transmitting a synchronization burst is a synchronization channel
  • Fig. 1 shows a case where satellite X has already established a frame synchronization state between the transmitter and receiver 10 and is transmitting and receiving signals using a communication burst. I have. Therefore, in Fig. 1, the channel used by satellite X is the communication channel of satellite X.
  • Satellites ⁇ and ⁇ show the case where the frame synchronization state has not been established between the transmitter and the receiver 10. Therefore, in FIG. 1, the satellite ⁇ or the channel used by the satellite ⁇ is the synchronization channel of the satellite ⁇ or the satellite ⁇ .
  • the receiver 10 receives the communication burst 31 X transmitted from the transmitter on the communication channel of the satellite X, and performs the receiving process 32 of the received communication burst. Further, the receiver 10 receives the synchronization bursts 2 1 Y and 21 Z transmitted to the synchronization channel of the satellite Y or the satellite Z between the reception processes 32 and performs the synchronization control process 33 .
  • the receiver 10 When the receiver 10 receives the synchronous burst 21 Y of the satellite Y, the synchronous code 23 Y can be received, but the synchronous codes 24 Y and 25 Y cannot be received.
  • the receiver 10 detects the received synchronization word 23 Y, and captures the frame of the satellite Y by using the detection result to maintain the frame synchronization.
  • the receiver 10 When the receiver 10 receives the synchronization burst 21 Z of the satellite Z, the synchronization word 24 Z can be received, but the synchronization words 23 Z and 25 Z cannot be received.
  • the frame of the satellite Z similarly to the case of the satellite Y, the frame of the satellite Z can be captured and the frame synchronization can be maintained.
  • Synchronous control processing 33 can be performed.
  • the receiver 10 can estimate the transmission timing of the communication burst 31X and the synchronization burst 21Y, 21Z in advance, the receiver 10 can further receive the synchronization code. As the performance increases, the number of times the synchronous control processing 33 is performed increases.
  • the receiver 10 attempts to detect all of the synchronization words 23, 24, and 25 and uses the detected synchronization code as a reference.
  • the position in the frame where the synchronous burst 21 is located is estimated, and the frame timing is Can also be controlled. In order to enable such an operation, it is desirable to make the cross-correlation between the synchronization codes 23 to 25 sufficiently small, and to minimize the probability of erroneous detection.
  • the frame capturing method and the frame capturing method when a plurality of channels having different frequencies are used have been described. Needless to say, the frame is more smoothly captured by the synchronous burst including the synchronous phase of the above.
  • the features of the frame acquisition method and method according to the present invention work effectively in a communication system using channels having different frequencies.
  • a synchronization burst including three synchronization words has been described as an example.
  • the number of synchronization words is not limited to three, and a plurality of synchronization words may be included in one synchronization burst. It is a feature of the present invention that it includes words.
  • the arrangement of the synchronization word in the synchronization burst is not limited to the example shown in this embodiment.
  • the present invention can be applied to communication systems other than the low and medium orbit mobile satellite communication systems.
  • the reception processing 32 of the communication burst and the synchronization control processing 33 of the processing of the synchronization burst are performed at different timings, but the timings of the two may conflict. This is because if there is no strong restriction on the circuit scale, etc., both can be realized by separate firmware.
  • the synchronization word can also be detected by the receiver 10 having the configuration shown in FIG. It is possible to detect frames, capture frames, and maintain frame synchronization.
  • the receiver 10 includes the synchronization / timing control unit 4 A
  • the processing up to 4C is performed for each synchronization word, and then the selection unit 6 selects the optimal timing control signal.
  • the processing of the selector 6 is performed after the processing of the synchronous word detectors 3A to 3C. That is, the selection unit 6 selects the synchronization word detection signals 104a to 104c on a predetermined basis.
  • 1 1 1 a to: 1 1 1 c is a selected synchronous code as a result of selecting the synchronous code detection signal 104 a to 104 c by the selection unit 6 based on a predetermined reference. This is a detection signal.
  • the processing is performed by the synchronization / timing control unit 4 using the selected synchronization mode detection signals 111a to 111c.
  • the synchronization ′ timing control section 4D outputs the synchronization ′ timing corresponding to the synchronization code detection signal 11 1 a to 11 c selected by the selection section 6. 4D circuit operates.
  • a communication burst and a synchronization burst using a channel having a different frequency from the communication burst are arranged so as not to compete with each other.
  • a synchronization burst is reliably received, a frame is captured, and synchronization is maintained.
  • the feature of this embodiment resides in the transmitter side.
  • the processing on the receiver side is not particularly described, as an example of a conventional technique, it is possible to realize this embodiment also with the receiver 10P described in FIG.
  • the receiver is not limited to the above-described receiver 10P, and may be another receiver having a function of capturing a frame.
  • FIG. 5 is a block diagram showing an example of a configuration for controlling a timing of transmitting a synchronization burst provided in a transmitter 70 for transmitting data.
  • the components denoted by the same reference numerals as those in FIG. 10 are the same as those described with reference to FIG. The same applies to the description using channel X, channel Y, and channel ⁇ .
  • channel X, channel Y, and channel ⁇ the same reference numerals as those in FIG.
  • Each of the synchronous burst arrangement circuits 71 A to 71 C is given an operation timing by a signal obtained by decoding the output of the frame counter 72 by the decoder 71.
  • the operation timing is given to the synchronous burst arrangement circuit 71 A of channel X.
  • the synchronous burst arrangement circuit 71 B of the channel Y is used.
  • the synchronous burst arrangement circuit of the channel Z is used. The operation timing of the circuit 71 is given.
  • the synchronous burst transmission timing of each channel is controlled by the frame power counter 702.
  • the communication burst arranging circuits 72A to 72C also determine the transmission timing so that the synchronization burst and its timing do not conflict. The mechanism for controlling the transmission timing of the communication burst is not described here.
  • FIG. 6 is a diagram illustrating an example of a relationship between a communication burst transmitted by the above-described transmitter and a synchronous burst.
  • FIG. 6 The components constituting FIG. 6 are the same as those in FIG. 1, and thus description thereof is omitted. It is assumed that satellite X in FIG. 6 uses channel X in FIG. Similarly, the following description is based on the assumption that satellite Y uses channel Y and satellite ⁇ uses channel ⁇ .
  • the synchronization bursts 21 ⁇ to 21 1 do not compete with the communication burst 31X. It is arranged in such a way.
  • the position of synchronous bursts 21 X to 21 Z is changed for each satellite, and Fig. 6 shows that synchronous bursts of different satellites are arranged for each frame. And different.
  • the timing at which the transmitter 70 transmits the synchronous bursts 21 1 to 21 ⁇ of satellite X, satellite Y, and satellite ⁇ is the same as that described in Fig. 5 so as not to conflict with the communication burst 31X. It is adjusted by the function of the machine 70.
  • the receiver is communicating using satellite X using channel X.
  • the receiver receives the synchronization burst 21X of the satellite X, the synchronization burst 21 1 of the satellite ⁇ , and the synchronization burst 21 1 of the satellite ⁇ .
  • the frame timing is estimated by detecting the synchronization word from the input 21 2 to 21 1. In this way, the frames of satellite X, satellite ⁇ , and satellite ⁇ ⁇ ⁇ ⁇ are captured, respectively.
  • the above operations can be performed only when the synchronization bursts 2 IX, 21,, and 21 ⁇ are received so that the synchronization words included in the synchronization bursts 2 IX, 21 ⁇ , 21 ⁇ of satellite X, satellite ⁇ , and satellite ⁇ can be received. This is because ⁇ 21 1 is arranged. Therefore, it is possible to smoothly capture frames and maintain frame synchronization for each of satellites ⁇ to ⁇ .
  • the frame capturing method and method according to the present invention it is possible to arrange the synchronization bursts 21 ⁇ to 21 ⁇ of each satellite so as not to compete with the communication burst 31X.
  • the synchronous burst 21 ⁇ ⁇ to 21 ⁇ ⁇ ⁇ of each satellite can be reliably received, and the frame can be captured smoothly.
  • the synchronization burst 21 has a minimum configuration including only a few known bit sequences required for demodulation and a synchronization code.
  • FIGS. 5 and 6 as an example, a case of a communication system using three channels having different frequencies has been described.
  • the number of channels is not limited to three.
  • the present invention can be applied to a communication system using a plurality of channels having different frequencies.
  • the receiver receives the communication channel and continues communication. In addition, it receives the synchronization burst allocated to the synchronization channel, captures the frame, and maintains the synchronization of the frame.
  • the synchronous burst can be realized by a conventional synchronous burst, but the synchronous burst including a plurality of synchronous words described in the first embodiment can also be used. .
  • Embodiment 1 or Embodiment 2 and Embodiment 3 are applied together.
  • the receiver only needs to have the functions as shown in FIG. 3 or FIG. 4 as an example.
  • the configuration of the synchronous bursts 21 X to 21 Z shown in FIG. 6 is changed to the configuration shown in FIG.
  • the probability of not being able to receive the synchronization code can be further reduced.
  • the synchronization burst of each satellite can be arranged so as not to compete with the communication burst, and the synchronization of each satellite can be ensured.
  • the burst 21 is received, and the frame can be captured smoothly.
  • the timing for transmitting the transmitter (base station) power synchronous burst for each satellite is scheduled in advance and the synchronous burst is transmitted.
  • the frame By transmitting the frame, it is possible to avoid a situation in which any one of the plurality of synchronization codes included in the synchronization burst cannot be received, so that the frame can be captured more smoothly.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Radio Relay Systems (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

Selon l'invention, tout en continuant une communication de données via un canal de communication, on capture une trame en utilisant un canal synchrone d'une fréquence différente de celle du canal de communication afin de réaliser facilement une diversité et un transfert inter-satellites. Durant la période pour laquelle, au moyen d'une rafale de communication (31X) via un canal de communication, aucune donnée n'est communiquée, on capture une trame au moyen de rafales synchrones (21Y,21Z) via un canal synchrone de fréquence différente. Puisque les rafales synchrones (21Y,21Z) comprennent des mots synchrones (23Y à 25Y,23Z à 25Z), les durées, pendant lesquelles aucune communication de donnée n'est reçue et pendant lesquelles on peut recevoir ces mots (23Y à 25Y,23Z à 25Z), sont donc augmentées. Dans une autre réalisation, les rafales synchrones (21Y,21Z) du canal de fréquence, déterminé à la fois pour l'émetteur et le récepteur, sont émises/reçues durant la période, et en conséquence la capture de trame est facilement réalisée.
PCT/JP1999/004576 1999-08-25 1999-08-25 Systeme de capture de trame, procede de capture de trame, et recepteur WO2001015375A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/JP1999/004576 WO2001015375A1 (fr) 1999-08-25 1999-08-25 Systeme de capture de trame, procede de capture de trame, et recepteur

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP1999/004576 WO2001015375A1 (fr) 1999-08-25 1999-08-25 Systeme de capture de trame, procede de capture de trame, et recepteur

Publications (1)

Publication Number Publication Date
WO2001015375A1 true WO2001015375A1 (fr) 2001-03-01

Family

ID=14236533

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP1999/004576 WO2001015375A1 (fr) 1999-08-25 1999-08-25 Systeme de capture de trame, procede de capture de trame, et recepteur

Country Status (1)

Country Link
WO (1) WO2001015375A1 (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07508623A (ja) * 1992-05-29 1995-09-21 モトローラ・インコーポレイテッド バースト・エラー保護データ同期機能を有するデータ通信受信機
JPH09271062A (ja) * 1995-09-20 1997-10-14 Motorola Inc 携帯無線電話用の組織的な走査方法および装置
JPH1023504A (ja) * 1996-07-02 1998-01-23 Japan Radio Co Ltd フレーム同期回路
JPH1065600A (ja) * 1996-08-20 1998-03-06 Sony Corp 移動通信装置および移動通信装置の無線回線切換制御方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07508623A (ja) * 1992-05-29 1995-09-21 モトローラ・インコーポレイテッド バースト・エラー保護データ同期機能を有するデータ通信受信機
JPH09271062A (ja) * 1995-09-20 1997-10-14 Motorola Inc 携帯無線電話用の組織的な走査方法および装置
JPH1023504A (ja) * 1996-07-02 1998-01-23 Japan Radio Co Ltd フレーム同期回路
JPH1065600A (ja) * 1996-08-20 1998-03-06 Sony Corp 移動通信装置および移動通信装置の無線回線切換制御方法

Similar Documents

Publication Publication Date Title
JP5079189B2 (ja) 多ビームセルラ無線基地局、移動機及びスペクトラム拡散信号送信方法
EP0665659B1 (fr) Système de communication mobile TDMA/CDMA
US5870427A (en) Method for multi-mode handoff using preliminary time alignment of a mobile station operating in analog mode
EP1119212B1 (fr) Appareil et procédé pour transférer des appels d'un système de communication mobile asynchrone vers un système synchrone
CN1568582B (zh) 移动通信系统中低码片速率选择的获取电路
US6549545B1 (en) Pilot signal detection method and receiver
JPH0480570B2 (fr)
WO1991003110A1 (fr) Methode de commande d'un commutateur de canal radio
JP2005094143A (ja) ダイバーシチ受信装置
CN107852380B (zh) 多信道可监听接收器及其操作方法
EP0938242B1 (fr) Terminal mobile sans fil et méthode d'économie d'énergie
US6430171B1 (en) Receiver apparatus for a random access channel of a CDMA mobile communication system
WO2001015375A1 (fr) Systeme de capture de trame, procede de capture de trame, et recepteur
EP0920148A1 (fr) Procede pour commander les communications d'un equipement mobile et equipement mobile
JP3399790B2 (ja) 周波数ホッピング送信方法及びその装置
JP3076308B2 (ja) 移動体通信システム
JP2000286766A (ja) ダイバーシティ受信装置
JPH11215051A (ja) 移動局送受信機
CA3016690A1 (fr) Recepteur, emetteur-recepteur, systeme de communication sans fil, et procede de communication sans fil
JP3597775B2 (ja) 衛星通信地上局
JPS5845870B2 (ja) フレ−ム同期引込方式
JPH0758665A (ja) スペクトル拡散通信用受信方法及び装置
KR100866209B1 (ko) 비동기 이동통신 시스템에서 기지국과 무선망 제어기간의연결 프레임 번호 결정 방법
KR100288200B1 (ko) 이동통신시스템의동기형복조장치및방법
JPH0530062A (ja) フレーム同期回路

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref country code: JP

Ref document number: 2001 518977

Kind code of ref document: A

Format of ref document f/p: F

AK Designated states

Kind code of ref document: A1

Designated state(s): JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase