JP3408229B2 - Slot synchronization acquisition method and apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a TDMA (Time Division Multiple Access) method in which the time to be transmitted by each mobile station is divided and used on the time axis using the same frequency. The present invention relates to a mobile station wireless device such as a mobile phone, a car phone, a self-employed digital wireless communication phone, and a slot synchronization acquisition method and device in a mobile communication system and the like configured by these.

[0002]

2. Description of the Related Art In a TDMA communication system, when transmitting a signal to a partner station by using a time slot having a fixed time width allocated in a frame, it is necessary to prevent mutual transmission signals from overlapping and interfering with each other in space. , It is necessary to adjust the transmission timing. The synchronization acquisition for this purpose is performed by detecting the unique word (synchronization word) in the transmission signal.

A conventional slot synchronization acquisition method will be described below with reference to FIGS. 7, 8 and 9. FIG. 7 shows an example of the configuration of the known series section in the slot. The unique words (UW) 701 to 704 have the same pattern and are repeatedly arranged at equal intervals.

FIG. 8 shows the result of correlation with the UW reference pattern when the known sequence of FIG. 7 is received from the UW 701 side, and the horizontal axis represents the time axis. The peak 801 is a correlation result P (t) when the UW701 is received at the timing t1.
1) and the peak 802 is UW7 at the timing t2.
02 is a correlation result P (t2) when received, a peak 803 is a correlation result P (t3) when UW603 is received at a timing t3, and a peak 804 is when a UW704 is received at a timing t4. Correlation result P (t4)
Is. Although it depends on the line state, normally, a peak occurs at the timing shown in FIG. 8 and no peak occurs at other timings.

FIG. 9 shows the correlation results of t4-t1 and t4-t when the correlation calculation is performed on the received data.
2, the result S of adding the correlation results before t4-t3 hours
(X) = P (x) + P (x- (t4-t3)) + P (x-
(T4-t2)) + P (x- (t4-t1)).
The peak 901 is the addition result S (t1) at the timing t1 and the peak 902 is the addition result S (t2) at the timing t2.
3 is the addition result S (t
3), and the peak 904 is the addition result S (t4) at the timing t4. A peak 805 is the addition result S (t5) at the timing t5 at time t4 to t3. Normally, the larger the length of the pattern for which the correlation is obtained, the larger the amount of calculation required. Therefore, relatively short UW patterns as shown in FIG. 7 are repeatedly arranged, correlations are obtained with the patterns as shown in FIG. 8, and the results are added at time intervals where all correlation values at each peak position are added. By carrying out, the main peak and sub-peak as shown in FIG. 9 can be obtained. This peak position can be acquired as the synchronization timing.

[0006]

However, in the above method, as shown in FIG. 8, the intervals between the timing t1 and the timing t2, the timing t2 and the timing t3, and the timing t3 and the timing t4 are equal. As shown in FIG. 9, sub-peaks other than the main peak 904 also become large. For example, the peak 903 is S (t
3) = P (t3) + P (t3- (t4-t3)) + P (t
3- (t4-t2)) + P (t3- (t4-t1)), and P (t3- (t4-t3)) = P (t2), P
Since (t3- (t4-t2)) = P (t1), P
It is a value obtained by adding the correlation results of (t3), P (t2), and P (t1). Therefore, if the timing at which the maximum value of the addition result occurs is the synchronization timing, the desired timing is the main peak position, but since the difference between the main peak and the subpeak is small, the possibility that the subpeak is mistakenly used as the synchronization timing increases. However, there is a problem that the accuracy of obtaining a desired synchronization timing is reduced.

The present invention is to solve the above-mentioned problems.
By increasing the difference between the main peak and the sub peak as a result of adding at the timing intervals at which W is arranged,
The possibility that the sub-peak is mistakenly used as the synchronization timing is reduced, and the desired synchronization timing can be accurately achieved.
An object of the present invention is to provide a slot synchronization acquisition method and apparatus in an MA communication system.

[0008]

In order to achieve the above object, the slot synchronization acquisition method according to the present invention inserts a unique word repeatedly into a known sequence portion in a slot, and when receiving the slot, the received data and the known sequence are received. When the correlation with the unique word of the unique word is obtained and then the addition is performed at the position address interval where the unique word is arranged, the largest peak at the timing when a plurality of correlation results of the position where the unique word is arranged are added. Is the main peak, and at the timing when the other sub-peaks are set, the unique word is arranged so that the address position for performing the addition at the timing when the sub-peaks are set does not overlap the arrangement position of the plurality of unique words. It is a thing. As a result, slot timing synchronization can be realized with high accuracy with a small calculation amount and a small memory usage amount.

Further, the slot synchronization acquisition device of the present invention is
Unique word detecting means for detecting the unique word from the received signal containing the unique word arranged by the slot synchronization acquisition method, and correlation calculation for calculating the correlation value between the detected unique word and the known unique word reference pattern. Means, delay means for delaying the reception timing of each unique word, adding means for adding the correlation result obtained from the correlation calculating means and the correlation result delayed by the delay means, and the addition result The maximum value detecting means for detecting the maximum value and the synchronization acquiring means for acquiring the synchronization at the timing when the maximum value is detected. As a result, slot timing synchronization can be realized with high accuracy with a small calculation amount and a small memory usage amount.

Further, the present invention is a mobile station radio apparatus including the above slot synchronization acquisition apparatus, and can realize a mobile station which can quickly acquire initial synchronization with a small memory usage.

Further, the present invention is a base station radio apparatus including the slot synchronization acquisition apparatus, and can realize a base station capable of quickly acquiring initial synchronization with a small memory usage.

Further, the present invention is a TDMA mobile communication system comprising the mobile station radio apparatus and the base station radio apparatus, and by using the mobile station radio apparatus and the base station radio apparatus, less memory is used. It is possible to build a system that can quickly acquire the initial synchronization by the amount.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. 1, 2, 3, and 4. (Embodiment 1) FIG. 1 shows the configuration of a slot synchronization acquisition apparatus according to the first embodiment of the present invention. In FIG. 1, a correlation calculation unit 101 performs a correlation calculation process between received data and a known UW reference pattern,
Output the correlation result. The delay devices 102 to 104 are provided for each UW.
The delay is given according to the reception timing of.
The adder 105 adds the correlation result obtained from the correlation calculation unit 101 and the correlation results delayed by the delay units 102 to 104. The maximum value detection unit 106 detects the maximum value of the addition result obtained by the adder 105. Synchronization acquisition unit 107
Acquires synchronization at the timing when the maximum value is detected in maximum value detection 106.

FIG. 2 shows an example of the configuration of the known sequence section in the slot according to the present embodiment.
Reference numeral 204 is a UW having the same pattern repeatedly arranged. FIG. 3 is a correlation result with the UW reference pattern when the known sequence of FIG. 2 is received from the UW 201 side, and the horizontal axis represents the time axis. Peak 301 is the correlation result P (T1) when UW201 is received at timing T1,
A peak 302 is a correlation result P (T2) when the UW202 is received at the timing T2, and a peak 303 is a correlation result P when the UW203 is received at the timing T3.
(T3), and the peak 304 is U at timing T4.
It is a correlation result P (T4) when W204 is received. Although it depends on the line state, normally, a peak occurs at the timing shown in FIG. 3, and no peak occurs at other timings.

In FIG. 4, in the present embodiment, when the correlation calculation is performed on the received data, the correlation result is delayed by the delay devices 103 to 105 shown in FIG.
-T1, T4-T2, T4-T3 The result of adding the correlation results before time S (x) = P (x) + P (x- (T4-T
3)) + P (x- (T4-T2)) + P (x- (T4-
T1)). The peak 401 is at the above timing T1.
It is the addition result S (T1) at the time of. Peak 402
Is the addition result S (T2) at the timing T2. The peak 403 is the above timing T1 + T4-T.
It is the addition result S (T1 + T4-T3) at the time point of 3.
The peak 404 is the addition result S (T3) at the timing T3. The peak 405 is the addition result S (T2 + T4-) at the timing T2 + T4-T3.
T3). The peak 406 is the above timing T1 +
Addition result S (T1 + T4-T2) at the time of T4-T2
Is. A peak 407 is the addition result S (T4) at the timing T4.

In the conventional example, the addition result S (T2) at the timing T2 is obtained by adding P (T1) and P (T2), and the addition result S (T) at the timing T3.
In (T3), since P (T1), P (T2), and P (T3) were added, a large subpeak was generated. However, in the present embodiment, in order to suppress the sub-peaks generated by the addition processing, the UW positions in FIG. 2 are arranged so that the peak occurrence positions in FIG. 3 do not overlap at the timing of the sub-peaks. That is,
By making the timings of the sub-peaks 401 to 406 not coincide with each other as much as possible, the sub-peak 40
The result of addition of timings 1 to 406 is the main peak 4
The addition result can be smaller than the addition result at the timing of 07. As a result, it becomes easy to detect the position of the maximum value from this addition result, and the slot synchronization timing can be acquired with high accuracy.

(Second Embodiment) Next, a second embodiment of the present invention will be described. FIG. 5 shows the configuration of the mobile station radio apparatus according to the present embodiment, which is the same as the configuration of the conventional mobile station radio apparatus except for the synchronizing unit 514, and therefore the description will be briefly described. In FIG. 5, the transmission data is compressed by the encoding unit 501, error correction encoded, and input to the waveform generation unit 502. The waveform generation unit 502 adds control data to the input transmission data and generates, for example, π / 4 shift QPSK modulation data from this data. The generated π / 4 shift QPSK modulation data is output to the DA conversion unit 503 under the control of the timing unit 515. In the DA converter 503, the π / 4 shift QPS
The K modulation data is converted into an analog signal, and the converted analog signal is output to the quadrature modulation unit 504. further,
The quadrature modulation unit 504 performs quadrature modulation, the mixer unit 505 converts the frequency to a desired frequency, the amplification unit 506 amplifies, and the shared unit 507 transmits the burst signal from the antenna 508 to the base station wireless device. It On the other hand, the signal received from the base station wireless device via the antenna 508 is frequency-converted by the mixer 509, quadrature-demodulated by the quadrature demodulator 510, and output to the AD converter 511 via the common unit 507. The AD conversion unit 511 converts the analog signal into a digital signal, and the digital signal is output to the digital detection unit 512 and the synchronization unit 514. A synchronization unit 514 including the slot synchronization acquisition device 514a described above.
Then, the unique word is detected, the reference timing of the frame is extracted, and the reception timing of the slot is obtained. The timing unit 515 gives this reception timing to the digital detection unit 512 and the waveform generation unit 502. Based on the given reception timing, the digital detector 512
After the digital signal input from the D conversion unit 511 is subjected to filter processing or the like, the decoding unit 513 performs error correction decoding on the data obtained by performing delay detection and removing the control data, and expands the data. To get the received data.

The above is the configuration of the mobile station radio apparatus, but the configuration of the base station radio apparatus is that the transmitting and receiving antennas are separate as shown in FIG. Not to send a signal. This is because the base station is the timing standard.
This is because the mobile station transmits and receives at the timing of the base station, and the base station transmits and receives at the timing of free running. However, when the mobile station is distant from the base station, the reception signal from the mobile station may be delayed due to the propagation delay. Therefore, the synchronization unit 614 detects the timing of the reception signal,
Reception timing is given to the digital detection unit 612. The other configurations and operations are the same as those of the mobile station radio apparatus described above, and therefore the reference numerals are given corresponding to the components of FIG.

As described above, according to the mobile station radio apparatus and the base station radio apparatus according to the second embodiment, when the conventional slot synchronization acquisition apparatus is applied to the mobile station radio apparatus and the base station radio apparatus, it is initially set. Although the synchronization acquisition time is long and a considerable hardware resource is required, the slot synchronization acquisition device described in the first embodiment is provided, so that the correlation value calculation processing can be performed at high speed and with hardware resource saving. To achieve acquisition, the disadvantages of the prior art can be overcome. In addition, by configuring a TDMA communication system using such a mobile station radio device and a base station radio device, the mobile station radio device and the base station radio device can quickly acquire initial synchronization, and thus save hardware resources. With it, you can build a high quality system.

[0020]

As described above, the method and apparatus for acquiring slot synchronization according to the present invention repeatedly inserts a UW in a known sequence portion in a slot, and receives the UW when the slot is received.
When obtaining the correlation with the pattern of, and then performing the addition at the position address interval where the UW is arranged, the largest peak is set as the main peak at the timing when a plurality of correlation results of the positions where the UW is arranged are added. At the timing when a sub-peak other than the above occurs, the address position where the addition is performed at the timing when the sub-peak occurs is a plurality of UWs.
This is characterized in that the UWs are arranged so as not to overlap with the arrangement position of 1., and there is an effect that the accuracy of detecting the main peak is improved and a highly accurate slot synchronization acquisition device can be obtained.

Further, the present invention is a mobile station radio apparatus and a base station radio apparatus equipped with the above slot synchronization acquisition apparatus, and a TDMA communication system using such a mobile station radio apparatus and a base station radio apparatus. Therefore, since the performance of slot synchronization acquisition is improved, it is possible to obtain the effect that quick initial synchronization acquisition can be realized with low hardware resources and at low cost.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a slot synchronization acquisition device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a configuration example of a pattern of a known sequence in a slot according to the first embodiment of the present invention.

FIG. 3 is a schematic diagram showing a correlation result with a UW reference pattern after receiving a known sequence pattern according to the first embodiment of the present invention.

FIG. 4 is a schematic diagram showing a result of adding correlation results according to the first embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a mobile station radio apparatus according to Embodiment 2 of the present invention.

FIG. 6 is a block diagram showing a configuration of a base station radio apparatus according to Embodiment 2 of the present invention.

FIG. 7 is a schematic diagram showing a configuration example of a known sequence pattern in a conventional slot.

FIG. 8 is a schematic diagram showing a correlation result with a UW reference pattern when a conventional known sequence pattern is received.

FIG. 9 is a schematic diagram showing a result of adding correlation results in a conventional example.

[Explanation of symbols]

101 Correlation calculation units 102 to 104 Delay device 105 Adder 106 Maximum value detection unit 107 Synchronization acquisition units 201 to 204 UW 301 to 304 of the same pattern inserted in the known sequence portion Peak of correlation result between UW 201 to 204 and UW reference pattern 401 to 406 Sub-peak 407 as a result of adding correlation results Main peaks 501 and 601 as a result of adding correlation results 506, 606 Amplifier section 507 Shared section 607 Transmit antenna 508 Shared antenna 608 Receive antenna 509, 609 Mixer section 510, 610 Quadrature demodulation section 511, 611 AD conversion section 512, 612 Digital detection section 513, 613 Decoding section

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04J 3/06 H04J 3/00

Claims (5)

(57) [Claims] 1. A unique word is repeatedly inserted into a known series portion in a slot, a correlation between received data and a unique word of the known series is obtained when the slot is received, and then a position address interval in which the unique word is arranged. In addition, when performing the addition, the largest peak is the main peak at the timing when a plurality of correlation results of the positions where the unique words are arranged are added, and at the timing when the other subpeaks are set, the timing at which the subpeaks are set is set. A slot synchronization acquisition method, characterized in that the unique words are arranged so that the address position for addition does not overlap the arrangement positions of a plurality of unique words. 2. A unique word detecting means for detecting the unique word from a received signal containing the unique word arranged by the slot synchronization acquisition method according to claim 1.
Correlation calculation means for calculating a correlation value between the detected unique word and a known unique word reference pattern, delay means for delaying the reception timing of each unique word, and correlation calculation means Addition means for adding the correlation result and the correlation result delayed by the delay means, maximum value detection means for detecting the maximum value of the addition result, and synchronization acquisition means for acquiring synchronization at the timing when the maximum value is detected. Slot synchronization acquisition device. 3. A mobile station radio apparatus including the slot synchronization acquisition apparatus according to claim 2. 4. A base station radio apparatus including the slot synchronization acquisition apparatus according to claim 2. 5. A TDMA comprising the mobile station radio apparatus according to claim 3 and the base station radio apparatus according to claim 4.
Communications system.