TW507458B - Uplink synchronization signal transmission in TDD systems - Google Patents

Abstract

A time division-synchronous code division multiple access (TD-SCDMA) communication network implements a frame structure having a constant slot size. Signaling information, including e.g., synchronization information, for a particular connection is superimposed at a predetermined offset from the beginning of a selected slot in the frame, and the offset is transmitted on the common broadcast channel (BCH). Also, the synchronization information preferably is transmitted in the same slot with the random access channel (RACH). To establish a communication link, a transmitter operating in the network selects a first code word and a first time location within an uplink time slot, superimposes the first code word on the first time location within the uplink time slot, and transmits the first code word in the chosen time location. A receiver searches for a match of the first code word in at least one time location in at least one time slot designated for the uplink, and determines a possibly empty set of likely candidates for code words and locations; and if the set of candidates is not empty, estimates the time difference between at least one of the candidates time locations and at least one of the predefined time locations.

Description

507458 V. Description of the invention (i) Related applications The present invention is related and claimed to be superior to the United States provisional application, Sequence 5 Tiger 60/188, 469 'Title " Uplink Synchronization Signal Transmission in TDD Systems ", Founded on March 10, 2000, the disclosure of this document is expressly incorporated in the present case and is a reference. BACKGROUND OF THE INVENTION The present invention relates generally to cellular communication systems, and in particular, to the use of time division proximities for operation. System and method of cellular communication network of technology 0 Public cellular communication network (public land mobile network) is now commonly used to provide voice and / or data communication services to users on the Internet. Information (such as voice, video, data ) Is encoded as a modulated RF carrier and transmitted across the air interface between a node such as a cellular communication network and a single or multiple remote terminals. Each cell in the network generally includes at least one base station transceiver Platform (BTS), also known as base station (BS), is controlled by the base station controller (BSC). It can be controlled through Node and the network Bsc is connected to the core telecommunication network. Examples of such control nodes may include mobile service switching centers such as connection-oriented, circuit-switched networks used to connect to, for example, PSTN and / or ISDN ( MSC) nodes, and General Packet Radio Service (GPRS) nodes used to connect to packet-switched networks such as the Internet. Cellular phones are commonly referred to as "remote terminals," "mobile stations," or "mobiles." An example of a terminal ". Other examples of remote terminals may include personal computers (PCs), personal digital assistants (PDAs), pagers, and so on. Some remote terminals also need to run many applications, such as Internet browsers and computers ---- V. Description of the invention (2) :: program. Various multimedia applications can also reside in the same remote terminal cell communication network using various operating modes (modulo, etc.) and various proximity technologies, such as frequency digital, dual, time division multiple proximity (TDMA), digital / minute V Multi-W Proximity (FDMA) A hybrid of the above technologies. In a -FDMA network, Γ ΐ Proximity (CDMA) or-on individual frequency bands in the carrier frequency spectrum ★ Two: V Tiger is based on these frequency bands as communication channels: = So: send. J flooded each other. For example, in the United States, the federal authority, the above: Communication operation 1_Spectrum area & can be further configured to the cell band pair, and is referred to as many narrow frequency TDMA networks such as EIA-5 53 or IS-19β The road can be made by these traditional styles?]) ΜΑ Department of green ,,,,. The sub-segmentation is the frequency band used by the continuous time slot, and I, including one or more, and a communication channel is usually organized into a continuous frame, each slot. These four slots are one, and some of these characteristics can be, for example, $ 服 枪 服 （D-AMPS) (TIA / EIA) " " European Posts & ^, s. Industry associations and electronics industry associations tu / EIA / is Automatic Communication (Similar) Standard " Publisher = Indicator I ::::: ^ One data burst and communicate with the base station: time slot The number of transmissions in the process is two percent, and the near- ^ channel is used to communicate with a frequency after being assigned; and 507458 V. Description of the invention (3) In the CDMA network, an item is an informational Data streaming and electronic transmission to be added (such as digitized voice, data, video) can be used and the table is high, the electronic signals of the meta-rate data streaming are combined with each other, and the latter is called a Yu trace sequence or expanded sequence 'M generated-spread spectrum signal. The information needed to decode the expanded spectrum signal (that is, the unique signature series) can be transmitted through the information channel (leading channel or control channel) to the desired using this information, The desired receiver can extract the informational data stream and communication channel from the spread spectrum tiger. k ^ u Ϊ "Time-sharing duplexing (then) proximity technology of the communication network can be used for uplink (UL) or downlink J Ϊ: evening time slot. 纟 In each time slot, a -Or multiple data envelopes = can be transmitted in any direction according to the proximity technology adopted. According to the base: two = the near meeting 3 can be transmitted from different time slots to the packet center. For transmitting the CDMA network and each other in each time slot;! :: The invention of this disclosure can be equivalently applied to the ™ A network and those who can seal it. In the TDMA_CDMA hybrid system, many digital video sharing technologies share And / or time slot selection, you can split the packet door and wide slot. The digital ::: technique can be divided into synchronous and asynchronous synchronization network bundles according to characteristics, and the girl sends data packets synchronously. Below ~ Second, the transmission is easy in a predetermined time slot in a frame structure, because most of the implementation of the synchronous proximity technology can be simpler, and it contains enough power at 1 mile to facilitate transmission. The synchronous proximity technology can also be simplified. Access in mobile terminal

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V. Description of the invention (4) ^ Algorithm. In a synchronous network, mobile ‘2 'received packets occupy a predetermined position within the frame. 1 receiver can: It will be particularly advantageous, in which the information signal is usually in accordance with the positive: CDMA network: the person in the appropriate transmission conditions, said the number: the displayed s information signals will also be received in an orthogonal manner. The mobile terminal is located in the mobile terminal and the synchronization system will move slightly relative to the base station.

; Variation [The mobile terminal must adjust the broadcast delay. Therefore, for the sake of practicality, the synchronization should be near: for the propagation delay, it must be implemented-an appropriate control mechanism to compensate for the propagation delay :::: must also invent an introduction. In one aspect, the present invention can provide-a method of cellular digital multi-proximity technology; a method for transmitting uplink synchronization information at a partitioned duplex :::: device. ：： Wu, in the uplink time slot at the transmitter end = a digital word Bu Ganhai on the first time slot in the chain time slot +: where the uplink time slot contains at least one, Set to >, each resource of a preamble signal; and = the channel and the first digital word transmitted from the transmitter end =, and the selected time position: Also: the perspective 'The present invention can provide- A method for transmitting and receiving uplink synchronization information from a cellular digital radio communication network by time division ::

507458 V. Description of the invention (5) is represented by the first digital character in the time slot of the uplink key that is super placed in a predetermined time position in a frame structure. The method includes the following steps: searching for a matching result of the first digital character at at least one time position in at least one time slot configured as an uplink; and determining the probability of the digital character and position The candidate is an empty set of possibilities; if the set of candidates is not empty, the time difference between at least one candidate time position and at least one predefined time position is estimated. Brief description of the figure For those skilled in the art, after reading the detailed description of the exemplary embodiments and accompanying drawings, the present invention and other objects, features and advantages will be obvious. Among them: FIG. 1 is a schematic diagram of a frame structure and a time slot structure of a TD-SCDMA communication system; FIG. 2 is a schematic diagram of a frame structure of a modified TD-SCDMA communication system according to the features of the present invention; Both modified ^. ⑶—Communication system, a schematic diagram of the time slot structure; Figure 4 shows the flow of a method for transmitting communication signals according to the features of the present invention.

FIG. 5 is a flowchart of a method for receiving a communication signal according to the features of the present invention. In the following, a detailed description section, such as the description of the second embodiment, without limitation, is provided with specific details for the thorough solution of the present invention Frame structure news and technology, etc. However, for those who are familiar with this skill,

507458 V. Description of the invention (6) It should be clear that the present invention must be implemented according to its examples. In other examples, the detailed descriptions of the two methods of the known two methods have been omitted, and the structure and frame structure diagrams are shown in the figure. "This is a kind of" time division ΓΛ? The focus of the present invention. Existing communication system :::: cut: close to the picture. It is only an example, and U &, ° and channel structure are shown in the standard mobile phone system (TS) " standard network. V2 1 It belongs to the two sub-frames 110 'each holding about 5a. In addition, the .'Q structure contains eight time slots, seven of which are ^ / ms. Each sub-frame 1 1 0 is the time of transmission. Slot. Tender: day t;: "/ material traffic time slot,-according to U8 Mchlps (hundreds of slots; ^ G.675 μ, this value can correspond to one traffic time slot includes two: piece The data segment 124 of each of the 864 slices' data, 3; slices; that is, 3 ° 4 is the data slice and a slice corresponding to 16 slices; Day 2: 4: The middle section of the slice is commented on 126, In one downlink section and ― ;; ::!; 1 :, you can come to the traffic time slot as needed. Configure these seven sections between m sections to include n time slots, and j Second, in the target case, the downlink area m + n = 7 The Haishang link section includes m time slots, of which the Lungs ^ 亍 link section L Λ4- partition. The signaling time slot package; two: the two-way section is divided by the signaling time slot 130⑽and—upper 128⑽TS), the back guard part includes a part called S :: "32⑽PTS). The downlink end is synchronized with the network. The uplink A 5 is a signal that can assist the end of the operation. Can assist the base ;: ==-™ 458, which is based on the synchronous operation of ordering links on the soil, and 507458 V. Description of the invention (7) Estimate the timing and power of mobile terminals. Existing TD-SCDMA The frame structure will be π B ~ channel (BCH), data, and "random access channel (RACH) π", which will list the specific positions in the signal center structure. This BCH 'can describe the configuration mode of the frame, and it will always be located at the first download slot (DL # 1). And the RACH 'when the mobile terminal requests access to the network, the user may load the "random access channel request" from the mobile terminal and will always be located in the time slot immediately after the UpPTS. In operation ’A certain line of terminals in the TD-SCDMA communication system will cause the information in DwPTS section 28 and UpPTS section 132 to access the network in parallel with the network. In short, in order to perform the initial synchronization operation, a mobile terminal operating in a TD-SCDMA cell searches for a signal received from Yoshida for a valid SYNC signal. In general, the ^ term & search is to use a matching filter library β that has been fine-tuned to receive the candidate s γ N c signal. When a valid sm signal is detected at the end of the operation: the mobile terminal can determine the frame structure of the first download slot (DL # 1). The second attack includes the definition of the frame configuration. Common broadcast channel (bch); '' · I mobile terminal can also use this frame configuration to estimate the approximate position of the upper slot of the uppts section 3-this can be discussed " random proximity frequency estimates for transmission The desired power ... can use the information on the rule when the mobile terminal intends to establish a disk _change & △ one by one and / ,,,, Kushiro's connection session, he can upload synchronization and random as follows: Proximity request process #: First, :: download synchronization is performed approximately as before. Money, the mobile terminal select-^ machine digital SYNC1 'and corresponding to the estimated by the mobile terminal 507458 V. Description of the invention (8) _

In the time slot of the UpPTS section 132, the mobile phone is transmitted to the United States A according to the desired work G estimated by the mobile terminal ^ The swollen 1 digital system The base station received from the mobile terminal】 °

The UpPTS section and the adjacent time slot are used to know whether the frame number is known or not. The base station will estimate the mobile terminal m based on the position of the bit segment Π2 in the 1 frame structure between the detected "SYNC1" and the expected position of the SYNC1 signal. ^ PPTS ..., Jun. Sadly σ re-evaluates the received SYNC1 signal

The difference between the true power of the SYNC1 signal. If the signal is not available, the timing and power correction base station is signaled on the j 2 shared and received channels, and then the F A C Η terminal reads out the timing function in the FACH channel;: = end. This operation adjusts its timing and power, and prepares for the same; on the second task, adjust a random access surge. "In the price? Π 宁 传 迗 ～ 二 ί 地 ΐ The periodic information update method between mobile terminals comes to the end. The base station can use the timing and power estimates to move the terminals together to maintain their main channel contacts. , 仃 The existing TD-SCDMA frame structure can be provided-provided by UppTS section 132 1ί: ^: 2 One-to-one mapping. At the same time, the size of the time slot is controlled to be two: set: it is solid and is different from the size of the data slot. This; 者 者) However, although the interface appears in an uncoordinated network, there are many technical issues. In particular, if the two temples are affected by various interfaces, it is necessary to move the transmission channels to the newsletter; page 13 507458 5. The slot of the invention description (9) is impossible. At the same time, in the uncoordinated operation of the two TD-SCDMA networks = the road is not aligned along the DWPTS section 128), then the interface from the first network to the next two links, or It will be connected to the UpPTS section 136 or RACH of the second network. The link between the government and the government will affect m 、 and Bei Shi 攮 ㈢, which will cause differential congestion on the two networks, because the uplink is definitely necessary. The initial setting of β for the connection operation Figure 2 = Another feature of the present invention-a kind of T, the structure has a time span

,: Special size. The uplink :: method in the frame structure (that is, the uplink / downlink configuration) can be determined in a divided way to provide two-way and effective. The frame structure is divided into two: j ;; such as In the specific embodiment, each of the downlink time slots and the frame has five (5) dedicated slots. According to the present invention, ~ ρ 彳-丝: (3) Anything in the frame structure that is exclusive to the uplink; the information (operational PTS) can be super-information (such as UpPTS) can be a super-delegator. Above, and above the uplink signaling slot. Liyi one-two. : In the frame structure, any uplink is placed in the embodiment including the body. The SYNC1 signal is a super signal when it is placed on the RACH link and time slot. Directly map this SYNC1. For example, ^ ^ generates an MNC1 signal and the RACH time slot. Advance— + The base station can know that the SYNC1 signal is configured and reconfigured to “if interference occurs, the SYNC1 can still be configured. In an exemplary embodiment,

Page 14 507458 5. In the description of the invention (ίο), the SYNC signal in the downlink can be super placed on the time slot with the right BCH. "In an exemplary embodiment of the old unused source, the SYNC1 signal can be super placed on the RACH time slot by adding this number. Similarly, the" "signal can be added. Add this signal It should be placed on the BCH time slot. It should be known that the surname Lt will have an extra signal 'for example, like other traffic and control. In addition, it should be understood that other coding rules can be implemented in order to The two superpositions illustrate the structure of an exemplary time slot 3. This can be an uplink or a time slot of the link. The time slot 3002 and 2: paragraph note 3.6 is separated from The second heart ^ is located in one and SYNC1 in the frame or in the uplink (NC). The system i may be solid.; = Shift: the time slot of the Π slot and the boundary. "The poor news is best not to interact with other actions in the lead time slot = f because this may interfere with the transmission to the * in the specific: to ;,] channel estimation operation. The distance between the mobile terminal and the mobile terminal transmitted by I6 仃 will be different from that of the base station. Therefore, the mobile terminal contains a slight error in the timing of the forward power furnace f. Many base stations make loops to correct this i. In the control system established with the mobile terminal, the difference between I and 2 days before the timing. There is almost zero operation with uplink synchronization. However, if the property is sufficient to assume that the timing error value is a non-zero timing error, the control loop is not established, and will appear. In this case, the mobile station can estimate when to transmit 507458

5. Description of the invention (π) The SYNC1 signal is kept relatively small in the timing error value. The action A ^ searches for a time near the expected time position of the SYNC1 signal; a window to capture the "仳 1" transmission signal with a relatively small timing error. The time sliding window generally reflects the size of the cell.

In a network that implements the frame structure as shown in Figure 2, mobile terminals can use a slightly modified synchronization process. Referring now to FIG. 4, an initial download synchronization operation will be performed, and the mobile terminal cell will search for the received k number 'from the base station to know if a valid S Y N C signal appears. Generally, this search is performed using a matching filter bank that has been fine-tuned to receive candidate SYNC signals. Since the BC system is placed in the time slot with synchronization, when the mobile terminal detects a valid SYNC signal, the mobile terminal can immediately determine the position within the BCH frame structure. The mobile terminal can determine the frame configuration by the signaling information in the BCH, which is obviously positioned on the RACH

And F A C position on the frame structure. The mobile terminal can use this quote to estimate the approximate location of SYNC1 and the upload time slot. The mobile terminal can also use the BCH information to estimate the desired power for transmission. Figure 5 shows an exemplary initial upload synchronization sequence. First, the action was performed as a download-sync operation. Then the "synchronous digital synci '" is started and the power is transmitted in the time slot corresponding to the ":"; The ci digital is based on the signal structure estimated by the mobile terminal, and the base station receives the signal structure of the RACH time slot and the adjacent two = automatic terminal, and scans the signal. The base station! = To check if there is a valid bit in the signal pivot structure detected by the "^ 1" signal

Page 16 V. Description of the invention (12) ^ The difference between the expected SY N C1 signal position and the estimated timing error of the mobile terminal. The base station then estimates the expected power of the received signal and the received signal ^ ⑽! The difference between the actual power of the signal = 丄 Then, what about the base station? The ACH channel signals the timing and power correction to the mobile terminal. The mobile terminal reads the meter 4 and power correction information in the fach channel, adjusts its timing and power accordingly, and prepares and transmits a random access surge in the designated RACH time slot. I use the same procedure, which is roughly related to the frame structure shown in Figure VII, to maintain uplink synchronization. The flexibility added by the frame structure shown in Figure 2 will require the base station to transmit additional signals on it, so that the mobile terminal can determine the uplink and downlink configurations according to sync and SYNC 1. And slot position. However, since the attack information changes only intermittently, updating this information does not consume excessive network resources. Note that it is not necessary to transmit the SYNC1 signal and the corresponding random proximity signal at the same time. That is, as shown in this article, the term " overlay " can actually mean that the SYNC1 signal is super placed on a received signal of a traffic message from another mobile terminal using the time slot (at the base Desk). Generally speaking, the mobile terminal issuing the SYNC1 is not already using the same time slot ', but this is not excluded. In the exemplary embodiment, the SYNC1 is transmitted only when the initial setting or when the uplink synchronization information needs to be added for reasons other than those received in the present disclosure. Here, the initial setting of the term means the initialization operation of a certain packet transmission (or may be packet transmission) in the packet branch type. V. Description of the invention (13) — '"' " ~ " ---- --- Or the initialization of the connection in the circuit switching mode. Medium = general embodiment The receiver in the base station will search for the valid set of received signal and digital character within the time slot = (positions) time position; i matches the result of i, and the location is via the base station It is determined that the signal is indeed located: 的 Γ is not accurate, the base station may need to search for a time sliding window at the most probable position = attached J. The base station then decides a set of probable candidates for the number of wives π /, position. If the candidate time slot is not empty, the base σ will estimate the time difference between at least one candidate time position and at least one. This time difference can be used as a signal

The mobile terminal adjusts its transmission time so that the base station can receive SYNC1 as close as possible to the normal position. Second, in a specific embodiment, the SYNC1 signal may be selected from a set of two or ancient t numbers or digital characters, and may be transmitted at a fixed position in the time slot (that is, in accordance with Fixed displacement of the starting point of the time slot f) In other specific embodiments, it can be a group of digital characters allocated to a specific cell, or a group of specific characters allocated to a specific network or network Among the digital characters, the digital word is selected in a random manner. In addition, multiple instances of the SYNC1 signal can be transmitted in the time slot, and these SYNC1 instances can have different digital characters. The control channel associated with this SYNC 1 may be RACH or another uplink control channel. > The present invention can be implemented in a network employing TDMA proximity technology, CDMA proximity technology, or the like. The present invention does provide a variety of advantages over existing TD-SCDMA communication networks. The invention can provide flexible uplink and downlink in the frame structure

Page 18 507458 Jade and invention description (14) Link slot configuration mode. In addition, the time slot is not limited to a specific function (such as DwPTS or UpPTS). Therefore, if necessary, time slots with racH or SYNC 1 channels can be configured to avoid interference. Furthermore, since the frame structure of the present invention locates the SYNC1 signal and the RACH signal in the same time slot, only a simple mapping method between the time slot where SYNC1 is located and the time slot where RACH is located is required. At the same time, the merged SYNC1 and CU can be reconfigured while still maintaining the aforementioned simple mapping method. ", Same

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Claims (1)

507458 6. Scope of patent application 1. A method for transmitting uplink synchronization information from at least one transmitter, which is used in a cellular digital radio communication system using time division duplex multiple proximity technology. The method includes the following: Steps: Selecting a first digital character on the transmitter side; Selecting a first time position in the uplink time slot on the transmitter side; placing the first digital character first in the uplink time slot Above the time position, wherein the uplink time slot contains at least one physical control channel and at least one preamble signal resource; and the first digital character is transmitted by the transmitter end in the selected time position . 2. For the method in the first scope of patent application, where the entity control channel is an entity random access control channel. 3. The method of claim 1 in the scope of patent application, wherein: the first digital character is selectively random. 4. The method according to item 1 of the patent application scope, wherein: the first time position corresponds to a RACH time slot. 5. The method of claim 1 in the scope of patent application, wherein: the first digital character is selected from a group of number-code characters. 6. The method of claim 1 in the scope of patent application, wherein the first time position is selected from a set of time positions. 7. The method according to item 1 of the scope of patent application, wherein: the multiple proximity method is digital division multiple proximity. 8. If the method of the first scope of the patent application, the multiple proximity method is time division multiple proximity. Page 21 507458 6. Scope of patent application 9. The method of the first scope of patent application, wherein the first digital character is selected from a group of digital character characters that have been allocated to a specific cell. 10. The method according to item 1 of the scope of patent application, wherein: the first digital character is selected from a group of digital characters that have been allocated to a specific network. 11. The method of claim 1 in the scope of patent application, wherein: the first time position is selected in a random manner. 1 2. The method according to item 1 of the scope of patent application, wherein the first time position is selected from a group of time positions that have been allocated to a specific cell. 1 3. The method according to item 1 of the scope of patent application, wherein: the first time position is selected from a group of time positions that have been allocated to a specific network. 14. The method according to item 1 of the scope of patent application, wherein: the uplink synchronization information transmission operation does not overlap with at least one preamble signal transmission operation retained by the mobile terminal. 1 5. The method-item of the first scope of patent application, which further includes the following steps: A second digital character is transmitted by the transmitter end within the selected time position of the group. 16. The method according to item 15 of the scope of patent application, wherein: In the uplink synchronization information transmission operation, at least two blocks will have different digital character selection results. Page 22 507458 6. Scope of patent application 1 7. — A method for receiving uplink synchronization information from at least one transmitter in a cellular digital radio communication network by time division duplex proximity method, wherein the synchronization The information is represented by the first digital character in the uplink time slot that is super placed in a predetermined time position in a frame structure, and includes the following steps: At least one time slot configured as an uplink At least one time position in the search for a matching result of the first digital character; and I determines the empty set of probable candidates for the digital character and the position, if the candidate set is not empty , The time difference between at least one candidate time position and at least one predefined time position is estimated. ·) Page 23