JP3201257B2 - Synchronous control device and method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a TDMA (Ti
me Division Multiple Access
The present invention relates to a synchronous control device and a synchronous control method applied to a communication system represented by ss (time division multiple access).

[0002]

2. Description of the Related Art The TDMA communication system is one of systems in which a communication transmission line capacity is divided and used by a plurality of stations physically located at different positions. FIG. 17 is a copy of TDMA written by Yamamoto and Kato
TDMA described in "Communication" (The Institute of Electronics, Information and Communication Engineers)
It is a figure showing the concept of communication. Communication between the mobile stations # 1 to #i and the base station is performed by transmitting radio line signals in bursts using time slots in a frame allocated by the base station. In order to prevent burst signals transmitted from each station from overlapping each other on a wireless line, it is necessary to control transmission timing. For this purpose, each station has a common “time reference”, and a transmission timing (transmission time reference) is set in consideration of a distance difference from each station to a receiving (base) station or a satellite (in the case of satellite TDMA communication). The former detects a specific signal (reference station synchronization signal) from the received signal and uses it as a time reference, so that the reception is synchronized. The latter determines the timing of a signal to be transmitted to the satellite, so that transmission synchronization (or burst synchronization) is performed. Called.

In the figure, 121, 122 and 12i are mobile stations, 123 is a base station, and t1, t2 and ti are burst signals. In the TDMA system, a TDMA frame is determined as a basic period of a burst signal transmission interval (or reception interval), and the frame is further divided into time slots (T1 to Ti) having a fixed time width. Mobile station (121,
122,..., 12i) receive a signal transmitted from the base station (123) to the mobile station to synchronize the frame and the time slot with the base station (123), and are allocated from the base station in this frame. The burst signal (t1,
t2, ti). Therefore, the mobile stations of i stations (t1 to ti) can transmit simultaneously in one frame.

In TDMA communication, a mobile station needs to synchronize its own transmission / reception frame timing with a base station so as not to collide with a burst signal of another station. Base stations,
Since both mobile stations have independent clock sources, frequency deviation between clocks must be removed. It is important for a mobile station to synchronize the frame timing with the base station and maintain the synchronization while removing the frequency deviation of the transmission clock, that is, how to implement so-called dependent synchronization.

FIG. 18 is a diagram showing a configuration of a conventional synchronization control device in a mobile station. In the figure, 1 is a receiving unit, 2 is a UW detecting unit that calculates a correlation of a specific pattern (unique word, hereinafter referred to as UW) in the received burst data and outputs a correlation signal, 3 is a data processing unit, and 4 is a frame. The counter 5 is a detection window for detecting a correlation signal at a predetermined position (referred to as an aperture gate, hereinafter referred to as an AP gate).
Is an AP control unit that generates Next, the operation will be described. A received signal received via an antenna (not shown) is demodulated in a receiving unit 1 and a burst data signal a
Is output as The data burst signal a is input to the UW detector 2 and also to the data processor 3. The UW detector 2 correlates with the UW consisting of a known fixed bit pattern in the burst data signal, and outputs a UW correlation signal b when there is a correlation.

FIG. 19 is a diagram for explaining the operation of the UW detector 2. The burst data a is a unique word (U) having a high correlation with P (preamble) as a synchronization word.
It consists of a known fixed bit pattern called W), a data and a CRC for detecting an error in the received data. U
The W detector 2 has a known fixed bit pattern UW pattern 130. The multiplier 131 multiplies the held UW pattern by the burst data signal a, and stores the result in a register 132. And register 1
The 32 bits are added by the adder 133 to determine an error bit for the UW pattern 130. The comparator 134 compares it with a predetermined UW detection threshold X. If the error bit is equal to or smaller than X, it is determined that UW has been detected, and the UW correlation signal b is output.

Referring back to FIG. The AP control unit 5 opens an AP gate of a fixed time width before and after the position where UW is to be detected from the frame timing signal d output from the frame counter 4 and only when the UW correlation signal b is input in time. The UW detection signal c is output. When the AP gate is not open, the UW correlation signal b is
Does not detect UW. FIG. 20 is a time chart showing this relationship. The UW detection unit 2 keeps correlating at all times, and outputs a UW correlation signal b if the correlation is obtained below the UW detection threshold. However, the UW correlation signal b (marked by X in the figure) when the AP gate is not open in the AP control unit 5 is not output as the UW detection signal c.

[0008] That is, the UW pattern correlation signal b includes so-called erroneous detection in which correlation is accidentally detected in thermal noise or random bits in data bits. The erroneous detection disturbs subordinate synchronization, hinders extraction of received burst data at a correct position, generates erroneous transmission timing, causes a collision with a transmission signal from another station, and is harmful. In TDMA communication, since communication is started after frame synchronization is established, the arrival time of a reception burst can be predicted within a certain range of error. The receiving station opens a window called an AP gate before and after the UW position uniquely determined by the arrival time of the burst, and performs UW detection only within the window, thereby suppressing erroneous UW detection.

The frame counter 4 is set to a predetermined value at which the UW detection signal should appear by the UW detection signal c output from the AP control unit 5, and corrects the held frame timing so as to be at a predetermined timing. Further, the frame counter 4 outputs a frame timing signal d serving as a reference signal for transmission / reception timing and a data processing timing signal f serving as a reference signal for transmission / reception burst data processing based on the corrected frame timing. The data processing unit 3 analyzes the received burst data a based on the data processing timing signal f. Further, transmission burst data is generated using the data processing timing f. The transmission burst data is modulated and transmitted by a transmission unit (not shown), and is provided as a transmission signal to a base station via an antenna (not shown).

FIG. 21 is a diagram for explaining the operation of the frame counter. When the UW detection signal c is detected, the frame counter 4 sets the value of the frame counter to a position (predetermined value) where the UW detection signal should be detected (timing A in the figure). Then, counting is continued from the set value, and reset at the head position of the frame generated from the internal clock of the mobile station (timing B). Generally, a TDMA frame created by a base station and a TDMA frame created internally by a mobile station are generated from independent clocks, so that a phase error occurs in frame timing due to a frequency deviation between clocks.

If the UW detection signal is not detected for some reason, such as at timing C, the frame counter 4 counts up and rotates at the frame period inside the mobile station to maintain the frame timing. Therefore, the detection timing of the last UW detection signal is stored,
Thereafter, a TDMA frame in the mobile station is generated from this timing until UW is detected again.

Here, a state in which the UW detection signal c is detected in the AP gate is called a synchronization state, and the UW detection signal c
The state in which is not detected is called out of synchronization. FIG. 22 is a diagram conceptually showing the synchronization state. Clockwise from the center is a + phase error, and counterclockwise is a-phase error. φa is the rotation angle of the relative frame timing phase per TDMA frame, and φb is the angle that is the boundary between the synchronized state and the out-of-sync state. The synchronization state is defined as the U of the burst received by the mobile station.
This refers to the state where the W position is within the AP gate. The out-of-synchronization state refers to a state other than the above-mentioned synchronization state. The angle A indicates the frame timing phase error accumulated due to the UW non-detection, and the state is out of synchronization when A ≧ φb.

Hereinafter, the synchronization state will be described with reference to a state transition diagram. If UW is not detected in state 0, the relative frame timing phase error becomes φa, and the state transits to state 1. If UW is detected, the state stays at 0. Similarly, in the state k (k ≦ N−1), the state transits to the state k + 1 on the right side in the case of a + phase error due to UW non-detection, and to the state K-1 on the left side in the case of a − phase error. . U
In the case of W detection, transition to state 0 is made. The accumulated frame timing phase error in the state k is k · φa (≦ φb). In state N, the state transits to state 0 upon UW detection,
The state shifts to an out-of-synchronization state (state N + 1) due to UW non-detection. When the out-of-synchronization state occurs, the UW is not detected thereafter, and the mobile station recognizes the out-of-synchronization state by some method and stays in the out-of-synchronization state until re-synchronization is performed. Normally, the mobile station recognizes that synchronization has been lost when UW is not detected continuously M times (M> N) after synchronization is once established. This is called front protection, and M is called the number of front protection steps. The optimal value of M is N + 1.

[0014]

In a communication system typified by the TDMA system, a plurality of users use one line in a time-division manner, so that interference with adjacent slots is avoided and transmission / reception is performed at an appropriate position. Therefore, synchronous control of frame timing is indispensable. Since frame timing synchronization is controlled by detecting UW, UW non-detection or UW erroneous detection poses a problem. The frequency of occurrence of UW non-detection or UW erroneous detection is related to the state of the radio channel, and it is not sufficient to perform a fixed synchronization control as conventionally performed. Further, since the frequency deviation between the communicating stations is uniquely determined by the mutual internal clock, it is inefficient to open the AP gate even at the time when UW is not detected unlike the conventional fixed synchronous control. It is. Further, by opening the AP gate at an unnecessary time, the possibility of erroneously detecting the UW is increased, which causes a synchronization error. The present invention has been made to solve the above-described problems,
It is an object of the present invention to provide a TDMA apparatus and method capable of receiving received data easily and accurately.

[0015]

A synchronization system according to the present invention
The control device performs a predetermined period of time that is repeated at the frame cycle for each station.
Burst using time slots allocated by width
Synchronous control of time division multiple access equipment that transmits and receives data signals
In the control device, the phase of the specific pattern contained in the received signal
Detecting means for outputting a correlation signal according to the degree of relation;
Signal output means for generating a timing signal
And the correlation signal at a predetermined value of the first timing signal.
Generating a controlled detection window for detecting the
Outputting a detection signal when the correlation signal appears in the window
Control means, the detection signal and the second timing signal
Phase difference detecting means for detecting a phase difference between
By the previous frame based on the phase difference detected by the
The average frequency deviation of the obtained phase difference is updated and a new frequency
Frequency deviation detecting means for determining a number deviation, the frequency deviation
From the frequency deviation detected by the detection means and the time width of the detection window
Synchronization that estimates the time to loss of synchronization and outputs the number of synchronization stages
Management means, and the timing
While adjusting the signal output means, the number of synchronization stages and the
Re-synchronization based on the number of discontinuous detections of the detection signal
Work.

Further , the synchronization control method according to the present invention comprises:
Allocated in a predetermined time width that repeats at the frame cycle for each station
Data signal in bursts using time slots
Control method for a time division multiple access device that transmits and receives
And outputs a timing signal at a predetermined timing.
Steps and specific patterns contained in the received signal.
The specific pattern detection signal and the timing
Detecting a phase difference from the
Find the frequency deviation of the timing signal based on the difference value
Synchronized from the step, this frequency deviation and the time width of the detection window
Steps to manage synchronization by estimating time to loss
Controlling the position of the detection window;
The data signal included in the received signal based on the received signal
And a processing step of performing processing.

Further , the synchronization control device according to the present invention comprises:
Allocated in a predetermined time width that repeats at the frame cycle for each station
Data signal in bursts using time slots
To the synchronization control device of the time division multiple access device
And generating a first and a second timing signal.
Signal output means, and a predetermined value of the first timing signal
Generates a controlled detection window for detecting the correlation signal.
The detection signal when the correlation signal appears in the detection window.
Control means for outputting a signal, the detection signal and the second timer.
Phase difference detection means for detecting a phase difference with the imaging signal,
Based on the phase difference detected by the phase difference detecting means,
Update the average frequency deviation of the phase difference obtained up to the frame
Frequency deviation detecting means for obtaining a new frequency deviation,
Based on the frequency deviation detected by the frequency deviation detecting means.
Estimating means for estimating an optimal time width of the detection window by using
Then, the detection window is generated based on the estimation.

Further, the synchronization control method according to the present invention comprises:
Allocated in a predetermined time width that repeats at the frame cycle for each station
Data signal in bursts using time slots
Control method for a time division multiple access device that transmits and receives
And outputs a timing signal at a predetermined timing.
Steps and detect specific patterns in the received signal
Step and the detected specific pattern detection signal and
Detecting a phase difference from the timing signal.
Frequency deviation of the timing signal based on the number of phase difference values
And a detection window based on the frequency deviation.
Estimating an optimal time span; and
Controls the position of the detection window based on the optimal window width of the bay window
And receiving a signal based on the timing signal.
A processing step of performing a receiving process of the included data signal;
Is provided.

Further, the synchronization control device according to the present invention comprises:
Allocated in a predetermined time width that repeats at the frame cycle for each station
Data signal in bursts using time slots
To the synchronization control device of the time division multiple access device
And the degree of correlation of a specific pattern contained in the received signal
Detecting means for outputting a correlation signal, first and second timings
A timing signal output means for generating a timing signal;
The correlation signal is detected at a predetermined value of the timing signal.
Generating a controlled detection window for the
Outputs the detection signal when the related signal appears and when it does not appear
Control means for outputting non-detection information, the detection signal and
Phase difference detection for detecting a phase difference with the second timing signal
Means, based on the phase difference detected by the phase difference detecting means.
And the average frequency deviation of the phase difference obtained until the previous frame
Frequency deviation detector that updates the difference and finds a new frequency deviation
Stage, the obtained frequency deviation and the non-detection information
Threshold control means for controlling a threshold for detecting the correlation signal based on the
And a timing signal output by the detection signal.
Adjust the force means and based on the frequency deviation
The position where the detection window is generated is controlled.

Further, the synchronization control method according to the present invention comprises:
Allocated in a predetermined time width that repeats at the frame cycle for each station
Data signal in bursts using time slots
Control method for a time division multiple access device that transmits and receives
And outputs a timing signal at a predetermined timing.
Steps and detect specific patterns in the received signal
Step and the detected specific pattern detection signal and
Detecting a phase difference from the timing signal.
Frequency deviation of the timing signal based on the phase difference
Determining and identifying based on the frequency deviation
Controlling a threshold value for pattern detection;
Receiving the data signal included in the received signal based on the
And a processing step of performing a communication process.

[0021]

[0022]

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a block diagram showing a configuration of a receiving device including the synchronization control device of the present invention. In the figure, 1
Is a reception unit, 2 is a UW detection unit, 3 is a data processing unit, 10 is an AP control unit, 20 is a frame counter, 30 is a phase difference detection unit, 40 is an averaging unit, a is demodulated burst data, b is a UW correlation signal, c is a UW detection signal, d is a frame timing signal, e is a synchronization timing signal, f is a data processing timing signal, g is a phase error signal, and h is a phase deviation information signal. Hereinafter, the operation will be described with reference to FIG. A received signal received by an antenna (not shown) is demodulated by the receiving unit 1 and output as received burst data a. The received burst data a includes a unique word (UW) having a specific fixed bit pattern. The UW detection unit 2 correlates the specific pattern stored in advance with the burst data a, and outputs a UW correlation signal b when the number is within a predetermined error bit. In the AP control unit 10, the frame counter 2
Based on the frame timing signal d output from 0, an AP gate having a fixed time width is opened before and after including a position where the UW detection signal c is to be output, and while the AP gate is open, the UW correlation signal b is opened. Only when detected, it is output as a UW detection signal c. Even if the UW detector 2 detects the UW correlation signal b, if it is not in the AP gate, the UW detection signal c is not output as erroneous detection.

The frame counter 20 generates a frame timing signal d for counting the frame length inside the mobile station. This frame timing signal d is modified by the UW detection signal c so as to be subordinately synchronized with the frame timing of the base station. The frame counter 20 outputs a synchronization timing signal e as a reference signal for synchronization control and a data processing timing signal f as a reference signal for transmission / reception burst data processing. The data processing timing signal f analyzes received burst data and processes data to be transmitted.

The phase difference detector 30 measures the phase error of the frame timing with respect to the base station from the error between the UW detection signal c and the synchronization timing signal e from the frame counter 20,
The phase error signal g is output. The averaging unit 40 averages the phase error signal measured so far and the frame timing phase error measured this time, calculates a frame timing phase deviation, and outputs a phase deviation information signal h. The AP control unit 10 controls the time at which the AP gate is opened for the estimated UW detection position based on the phase deviation information signal h.

FIG. 2 is a diagram showing the operation of the frame counter 20. When the UW detection signal c is not input, the frame counter 20 outputs a synchronization timing signal e when a predetermined value (n _{S in the} figure) is reached in the frame period inside the mobile station. The frame period when there is no UW detection signal c is not always synchronized with the frame period of the base station. In addition, a shift is caused by the frequency deviation. UW
It is set to an appropriate value (predetermined value) by the detection signal c,
Continues counting from the set value, and the frame length value n _F
After counting to the beginning, it is reset at the beginning of the frame. Here, the predetermined value of the counter is a position where the UW should be detected from the configuration of the burst data (the predetermined value of the counter n).
_S ). Upon UW detection, the frame counter set stores the difference between the predetermined value n _S and the count value of the frame counter when the UW detection signal appears, and adds the difference to the count value after the AP gate is closed. Set by doing. That is, in the figure, when the UW detection signal c is detected, the value of the frame counter is set to an upper value if the value is smaller than a predetermined value n _S , and is set to a lower value if the value is larger than the predetermined value n _S. Is shown.

FIG. 3 is a diagram for explaining the operation of the phase difference detector 30. The phase difference detector 30 measures a frame timing phase error from an error between the output timing of the UW detection signal c and the output timing of the synchronization timing signal e, and outputs a phase error signal g. FIG. 3 shows the relative frame timing phase error of the base station with respect to the mobile station frame timing centering on the synchronization timing signal e. As for the frame timing phase error, right rotation with respect to the center is defined as + phase error, and left rotation is defined as-phase error. In the figure, φα represents the minimum unit of the frame timing phase error that can be detected by the phase difference detection unit 30. In the illustrated example, the phase error signal g is UW
When the detection signal c is detected at the timing A,-| M
And || N | when detected at the timing B.

FIG. 4 is a diagram for explaining the operation of the averaging section 40. Here, for simplicity, it is assumed that UW is detected for each TDMA frame. However, in general, it is necessary to perform control such that the phase error signal g when UW is not detected is not used as data to be averaged. D0, d1,
... are the values of the phase error signal for each TDMA frame,
Generally represented as di. The averaging unit 40 holds a phase deviation obtained by averaging the phase error signal di measured in the past, updates the phase deviation with the phase error measured this time, and updates the frame timing phase between the new mobile station and the base station. The deviation is calculated and output as a phase deviation information signal h. Here, the method of averaging can be realized by applying a simple average, a root-mean-square, or the like of the phase error signal di in an accumulated frame or a plurality of recent frames.

The phase deviation information h obtained in this manner is input to the AP control unit 10 to control an AP gate for detecting the UW detection signal c of burst data of the next frame. That is, when the phase deviation information signal h is a positive phase deviation as shown in FIG. 5, the time to open the AP gate is delayed from the frame timing signal d by an offset corresponding to the phase deviation. When the phase deviation information signal h is a negative phase deviation, control is performed such that the time to open the AP gate is advanced by an offset corresponding to the phase deviation with respect to the frame timing signal d.

Embodiment 2 FIG. FIG. 6 is a flowchart illustrating a synchronization control method according to the first embodiment. A burst data signal composed of a unique word signal, a data signal and the like is input (step 1). Next, a unique word signal included in the burst data is detected (step 2). A phase error between the unique word detection signal and the frame timing signal is detected (step 3). The detected plural phase errors are averaged (step 4), and a frequency deviation between the base station and the mobile station is obtained (step 5).
An aperture gate (AP) based on the frequency deviation
Is determined (step 6). Control is performed so that the AP gate position after the next received frame is offset (step 7). The data signal in the burst data is processed based on the frame timing signal (step 8).

Embodiment 3 FIG. 7 is a configuration example showing another embodiment of the present invention. In the figure, 1 is a receiving unit,
2 is a UW detector, 3 is a data processor, 11 is an AP controller, 20 is a frame counter, 30 is a phase difference detector, 4
0 is an averaging unit, and 50 is a synchronization management unit. Further, a is demodulated burst data, b is a UW correlation signal, and c is UW
A detection signal, d is a frame timing signal, e is a synchronization timing signal, f is a data processing timing signal, g is a phase error signal, h is a phase deviation information signal, and i is a protection stage number signal.

The operation will be described below with reference to the drawings. The AP controller 11 determines the UW determined by the frame timing signal d.
Open the AP gate for a certain time before and after the detection position of
The UW detection signal c is output only when the W pattern correlation signal b is detected within the time when the AP gate is open. The synchronization management unit 50 determines the phase deviation information signal h and the AP having a known time width.
An optimum value of the number of forward protection stages is estimated from the gate, and a protection stage number signal i is output. When the UW non-detection continues and the number of UW non-detections becomes larger than the value of the protection stage number signal i, the AP control unit 11 determines that the state has shifted to the out-of-synchronization state, and performs a resynchronization pull-in operation of the frame timing.

The operation of the synchronization management unit 50 will be described with reference to FIG.
In the drawing, Φ is a frame timing phase error which is a boundary between a synchronous state and an out-of-sync state. If the absolute value of the value of the phase deviation information signal h output from the averaging unit 40 is A, then A ≧
The optimal value of the number of forward protection stages in the range of Φ is 0, Φ ≧ A ≧ Φ / 2
The optimal value of the number of forward protection stages in the range is 1. Generally, assuming that the optimum value of the number of forward protection stages is n (n is a natural number), Φ / n ≧ A ≧ Φ / (n + 1). Therefore, the protection stage number signal i becomes n in the above equation according to the value of the phase deviation information signal h.

FIG. 9 is a diagram showing the configuration of the AP control unit 11. In the figure, 110 is an AP gate generation unit, 111 is a counter, 112 is a comparator, 113 is a synchronization pull-in unit, s
Is a UW non-detection signal, t is a continuous UW non-detection signal, u is an out-of-sync signal, and w is a synchronization pull-in signal. Hereinafter, the operation of the AP control unit 11 will be described with reference to the drawings. The AP gate generator 110 opens the AP gate before and after the UW detection position estimated based on the frame timing signal d. When the UW pattern correlation signal b is not detected within the time when the AP gate is open, the UW non-detection signal s is output. The counter 111 increments the counter value each time the UW non-detection signal s is detected, resets the counter value when the UW detection signal c is detected, and outputs a continuous UW non-detection signal t. Comparator 1
Reference numeral 12 compares the continuous UW non-detection signal t with the protection stage number signal i, and outputs an out-of-synchronization signal u when the continuous UW non-detection signal t is larger. Upon detecting the out-of-synchronization signal u, the synchronization pull-in unit 113 performs a re-locking operation of the frame timing synchronization of the mobile station with respect to the base station frame timing,
When the re-locking of the frame timing synchronization is completed, a sync pull-in signal w is output. The specific operation of the synchronization pull-in unit 113 is not the essence of the present invention and will not be described. When the comparator 112 detects the synchronization pull-in signal w, the comparator 112 stops outputting the out-of-synchronization signal u. The AP gate generator 110 stops operating while the out-of-synchronization signal u is detected. With the above operation, the AP control unit 11 recognizes the out-of-synchronization state when the UW non-detection has continuously occurred, and redraws the frame timing synchronization with the base station frame timing.

Embodiment 4 FIG. This embodiment relates to a synchronization control method corresponding to the third embodiment. FIG. 10 is a flowchart of the control method. Until obtaining a frequency deviation between the base station and the mobile station is the same as FIG. The optimum number of synchronization protection stages is estimated based on the frequency deviation and the time width of the AP gate (step 6). If UW non-detection continues due to fading or the like, the number of frames t is counted, and step 6 is performed.
(Step 7).
It is determined whether or not the comparison result is i ≧ t (step 8).
If ≧ t, data processing in the burst signal is performed based on the frame timing signal. If a <b, it is determined that synchronization has been lost, and a synchronization re-pulling operation is started (step 10).

Embodiment 5 FIG. 11 is a configuration example showing another embodiment of the present invention. In the figure, 12 is an AP
A control unit, 60 is an estimation unit, j is an AP control signal, and the other components are the same as those in FIG. The operation will be described below with reference to FIG. The AP control unit 12 opens an AP gate having a fixed time width before and after the UW detection position determined by the frame timing signal d, and only when the UW pattern correlation signal b is detected within the time when the AP gate is open, the UW detection signal. Output c. The estimating unit 60 estimates an optimal AP gate time width from the phase deviation information signal h so as to keep the synchronization protection time constant, and outputs an AP control signal j. The AP control unit 12 opens the AP gate at a designated time based on the AP control signal j.

FIG. 12 is a diagram for explaining the operation of the estimating unit 60. In the figure, Φ1 and Φ2 are the rotation amounts of the frame timing phase between the own station and the other station per reference time, ε (Φ1), ε
(Φ2) is the phase deviation information signal h. Estimation unit 60
Calculates N × ε (Φ1) and N × ε (Φ2) in the figure according to the phase difference information signal h so that the synchronization protection time becomes constant, and outputs it as the AP control signal j.

Embodiment 6 FIG. The communication method will be described with reference to FIG. Until the frequency deviation between the base station and the mobile station is determined, it is the same as that in FIG. The time width of the aperture gate is adjusted so that the number of synchronization protection stages is constant irrespective of the magnitude of the frequency deviation (step 6), and the UW after the next received frame is detected. The data signal in the burst data signal is processed based on the frame timing signal (step 7).

Embodiment 7 FIG. 14 is a configuration diagram showing another embodiment of the present invention. In the figure, 13 is an AP
A control unit 70 is a UW detection threshold control unit, k is a UW non-detection information signal, m is an AP control signal, and the other components are the same as those in FIG. Hereinafter, the operation will be described with reference to FIG. The AP control unit 13 opens an AP gate having a predetermined time width before and after the UW detection position determined by the frame timing signal d, and only when the UW pattern correlation signal b is detected within the time when the AP gate is open, the UW detection signal. Output c. If the UW pattern correlation signal b cannot be detected within a predetermined time, the AP control unit 13 sets the UW non-detection information k
Is output. The UW detection threshold control unit 70 includes an averaging unit 40
Based on the phase deviation information signal h and the UW non-detection information k, the optimum UW detection threshold is estimated at each time, and the UW detection threshold information m is output.

FIG. 15 is a diagram for explaining the operation of the UW detection threshold control unit 70. In the figure, φ represents the phase error between the base station and the mobile station for each frame. In the frame in which UW is detected, in the next received frame, the frame phase of the mobile station with respect to the frame phase of the base station rotates by φ based on the phase deviation. In this case, the UW detection threshold control unit 70 operates to lower the UW detection threshold near the time corresponding to the frame phase error φ and increase the UW detection threshold at times other than the above. The frame phase of the mobile station relative to the frame phase of the base station rotates by 2φ when UW is not detected in one received frame. In this case, the UW detection threshold control unit 70 operates to lower the UW detection threshold near the time corresponding to the frame phase error 2φ, and increase the UW detection threshold at times other than the above. Hereinafter, the UW detection threshold control unit operates in the same manner even when UW is not detected in two or more received frames.

Embodiment 8 FIG. FIG. 16 is a flowchart of a synchronization control method according to the seventh embodiment. A burst data signal composed of a unique word signal, a data signal and the like is input (step 1). Next, a unique word signal included in the burst data is detected (step 2). If a unique word is detected as a result of the detection (step 3), a phase error between the unique word detection signal and the frame timing signal is detected (step 4). Then, a plurality of detected phase errors are averaged (step 5), and a frequency deviation between the base station and the mobile station is obtained (step 6). If no unique word is detected in the determination in step 3, the number of frames in which a unique word is not continuously detected is counted (step 7). Based on the frequency deviation obtained in step 6 and the number of frames in which UW has not been continuously detected counted in step 7, the optimum U
A W detection threshold is determined (step 8). The data signal in the burst data is processed based on the frame timing signal (step 9).

Since the present invention is configured as described above, the following effects can be obtained.

AP according to frame timing phase deviation
By applying an offset to the opening timing of the gate, erroneous detection of UW is prevented in a direction in which the time width of opening the AP gate with respect to the estimated UW detection position is small, and
In the direction in which the time width during which the gate opens is wide, the time interval until the synchronization is lost can be lengthened.

Also, by estimating the time in the synchronization protection state according to the detected amount of the frame timing phase deviation,
It is possible to reduce the time required for re-locking when synchronization is lost.

Further, by adjusting the AP gate width in accordance with the detection amount of the frame timing phase deviation and keeping the number of forward protection stages constant, the time until re-locking in the event of loss of synchronization can be reduced.

Also, based on the detected amount of the frame timing phase deviation and the number of frames in which UW is not detected continuously,
By controlling the UW detection threshold, it is possible to easily maintain synchronization, prevent erroneous UW detection, and perform accurate UW detection.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram illustrating an operation of the frame counter according to the first embodiment of the present invention.

FIG. 3 is a diagram for explaining the operation of the phase difference detection unit according to the first embodiment of the present invention.

FIG. 4 is a diagram illustrating an operation of an averaging unit according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating an operation of the AP control unit according to the first embodiment of the present invention.

FIG. 6 is a flowchart illustrating an operation according to the first embodiment of the present invention.

FIG. 7 is a block diagram showing a second embodiment of the present invention.

FIG. 8 is a diagram illustrating an operation of a synchronization management unit according to the second embodiment of the present invention.

FIG. 9 is a diagram illustrating an operation of an AP control unit according to the second embodiment of the present invention.

FIG. 10 is a flowchart illustrating an operation according to the second embodiment of the present invention.

FIG. 11 is a block diagram showing a third embodiment of the present invention.

FIG. 12 is a diagram illustrating an operation of an estimating unit according to the third embodiment of the present invention.

FIG. 13 is a flowchart illustrating an operation according to the third embodiment of the present invention.

FIG. 14 is a block diagram showing a fourth embodiment of the present invention.

FIG. 15 is a diagram illustrating an operation of a UW detection threshold control unit according to Embodiment 4 of the present invention.

FIG. 16 is a flowchart illustrating an operation according to the fourth embodiment of the present invention.

FIG. 17 is a diagram illustrating the concept of TDMA.

FIG. 18 is a conceptual diagram illustrating a conventional mobile station.

FIG. 19 is a diagram illustrating an operation of an AP control unit of a conventional mobile station.

FIG. 20 is a diagram illustrating an effect of an AP control unit of a conventional mobile station.

FIG. 21 is a diagram illustrating an operation of a frame counter of a conventional mobile station.

FIG. 22 is a diagram for explaining conventional synchronization protection management of a mobile station.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Receiving part, 2 UW detection part, 3 Data processing part 5, 10, 11, 12, 13 AP control part, 4, 20
Frame counter, 30 phase difference detection unit, 40 averaging unit, 50 synchronization management unit, 60 estimation unit 70 threshold control unit.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H04J 3/00-3/26 H04L ^7/ 00-7/10

Claims (6)

(57) [Claims] 1. A predetermined method which repeats at a frame period for each station.
Burst using time slot allocated by time width
Of a time division multiple access device that transmits and receives data signals
In the phase control device, the correlation signal is
Detecting means for outputting a signal, and first and second timing signals
Timing signal output means for generating the first
For detecting the correlation signal at a predetermined value of the
Generating a controlled detection window, and within the detection window the correlation signal
Control means for outputting a detection signal when a signal appears,
Detecting a phase difference between the output signal and the second timing signal.
Phase difference detection means, and the phase difference detection means
Of the phase difference obtained up to the previous frame based on the phase difference
Frequency for updating the average frequency deviation and finding a new frequency deviation
Number deviation detecting means, detected by the frequency deviation detecting means
From the frequency deviation and the detection window time width to the loss of synchronization
Synchronization management means for estimating the interval and outputting the number of synchronization stages,
Adjusting the timing signal output means by the detection signal
And the discontinuous detection of the number of synchronization stages and the detection signal.
The resynchronization pull-in operation is performed based on
Synchronous control device. 2. A predetermined method which repeats at a frame period for each station.
Burst using time slot allocated by time width
Of a time division multiple access device that transmits and receives data signals
Outputting a timing signal at a predetermined timing in the period control method
And a step of detecting a specific pattern contained in the received signal.
, The specific pattern detection signal and the timing signal.
Detecting the phase difference with the signal,
Step for determining the frequency deviation of the timing signal based on the
Out of synchronization from the frequency deviation and the time width of the detection window
Steps to manage synchronization by estimating time to
Controlling the position of the window;
Performs reception processing of the data signal contained in the reception signal based on the
Synchronous control, comprising:
Method. 3. A predetermined method which repeats at a frame period for each station.
Burst using time slot allocated by time width
To the division multiple connection device when transmitting and receiving data signals
Signal for generating first and second timing signals in the period control device
Output means; and a predetermined value of the first timing signal.
Generating a controlled detection window for detecting the correlation signal;
A detection signal is output when the correlation signal appears in the detection window.
Control means for applying, the detection signal and the second timing
Phase difference detection means for detecting a phase difference from the
The previous frame based on the phase difference detected by the phase difference detection means
Update the average frequency deviation of the phase difference
Frequency deviation detecting means for determining a frequency deviation,
Based on the frequency deviation detected by the number deviation detecting means,
Estimating means for estimating the optimum time width of the detection window.
Generating the detection window based on the estimation.
Synchronous control device. 4. A predetermined method which repeats at a frame period for each station.
Burst using time slot allocated by time width
Of a time division multiple access device that transmits and receives data signals
Outputting a timing signal at a predetermined timing in the period control method
And a step for detecting a specific pattern contained in the received signal.
And the detected specific pattern detection signal and the type
Detecting a phase difference from the
Calculate the frequency deviation of the timing signal based on the phase difference value
The optimal detection window based on this frequency deviation.
Estimating a time width; and
Step to control the position of the detection window based on the optimal time width
Included in the received signal based on the timing signal.
And a processing step of performing a data signal receiving process.
Synchronous control method characterized by the above-mentioned. 5. A predetermined method which repeats at a frame period for each station.
Burst using time slot allocated by time width
Of a time division multiple access device that transmits and receives data signals
In the phase control device, the correlation signal is
Detecting means for outputting a signal, and first and second timing signals
Timing signal output means for generating the first
For detecting the correlation signal at a predetermined value of the
Generating a controlled detection window, and within the detection window the correlation signal
Outputs a detection signal when appears and does not detect when it does not appear
Control means for outputting information, the detection signal and the second
Phase difference detecting means for detecting a phase difference between the timing signal
And, based on the phase difference detected by the phase difference detecting means,
The average frequency deviation of the phase difference obtained up to the previous frame is
Frequency deviation detecting means for updating and finding a new frequency deviation
And the detected frequency deviation and the non-detection information.
Threshold control means for controlling a threshold for detecting the correlation signal
And outputting the timing signal according to the detection signal.
Adjust the means and based on said frequency deviation
Synchronization system characterized by controlling the generation position of the detection window
Control device. 6. A predetermined method which repeats at a frame period for each station.
Burst using time slot allocated by time width
Of a time division multiple access device that transmits and receives data signals
Outputting a timing signal at a predetermined timing in the period control method
And a step for detecting a specific pattern contained in the received signal.
And the detected specific pattern detection signal and the type
Detecting a phase difference from the
Calculate frequency deviation of timing signal based on phase difference value
And the step of determining the specific pattern based on the frequency deviation.
Controlling a threshold value of the timing signal;
Of the data signal included in the received signal based on the signal
And a processing step of performing
Control method.