CN102075862A - Method for sending signal by using communication system - Google Patents

Abstract

A method for sending signals in a communication system, comprising the steps of: a sending end simultaneously transmits signals on shared wireless resources; a receiving end counts the state of the sending end according to the signals received on the wireless resources. The multicast broadcast service feedback channel method of the present invention can not only effectively collect channel state information of multiple sending ends, reduce false alarm and missed detection probability, but also save wireless channel resources compared with traditional feedback channel schemes.

Description

Method for sending a signal in a communication system

technical field

The invention relates to a multi-carrier wireless transmission system, in particular to a feedback method based on Multicast Broadcast Service (MBS).

Background technique

"Wireless + broadband" has become one of the current trends in network development, and various wireless communication systems compete fiercely in the field of broadband wireless access. And WiMAX (World Interoperability for Microwave Access Forum, global microwave access interoperability standard) is one of the broadband wireless access systems that has attracted much attention. WiMAX has entered the stage of scale testing and even commercial use in Europe, America, Japan, South Korea and other countries. It has the characteristics of large coverage, high transmission rate, high-speed mobile support, high spectrum efficiency, fast network construction speed, and low construction cost. With the popularization of trial commercial and commercial activities, WiMAX will have a good development prospect.

WiMAX is based on the IEEE 802.16 series of standards. In the IEEE 802.16 series of standards, 802.16-2004 (also known as 802.16d) and 802.16-2005 (also known as 802.16e) are currently the two most successful standards. In particular, the release of 802.16e has become a milestone in the field of broadband mobile communications. IEEE 802.16-2004 supports fixed and nomadic line-of-sight (LOS) and non-line-of-sight (NLOS) transmissions. In the line of sight environment, it can work in the 10GHz ~ 66GHz frequency band. In non-line-of-sight environments, it can work in frequency bands less than 11GHz. IEEE 802.16-2005 supports handover and roaming functions, can be applied in the mobile environment of vehicle speed, and mainly works in the frequency band less than 6GHz.

With the continuous improvement of the requirements of the sending end, future multimedia services will be more and more frequently applied to mobile terminals (Mobile Station, MS), and the WiMAX system is very conducive to the development of mobile streaming services. With the development of mobile streaming media services in the future, on a mobile terminal, the traffic of multicast services is likely to be significantly higher than that of unicast services. In order to meet the future market demand for streaming media services, IEEE 802.16 series standards provide Multicast Broadcast Service (MBS). Similar to the Multimedia Broadcast and Multicast Service (MBMS) formulated by 3GPP and the Broadcast and Multicast Service (BCMCS) formulated by 3GPP2, it also provides support for multimedia broadcast and multicast functions.

The WiMAX access network carries MBS services through public wireless connections. IEEE 802.16e defines two MBS access methods: single BS access and multi-BS access. For these two methods, ARQ (autorepeat request) is not applicable. Single base station (BS) access is realized in a BS through a multicast broadcast connection, that is, multicast broadcast works independently in each BS, carrying the wireless connection identifier (CID, Connection identifier) of MBS data and the connection identifier associated with the connection. The corresponding security association (SA, Security Association) parameters are the same for all MSs in the BS. Each participating MS receives and processes the data corresponding to the CID through the MAC layer, so the multicast broadcast connection of each BS only needs to transmit the multicast MAC data packet once. In the multi-BS access mode, multiple BSs will form an MBS zone (MBS_Zone), and each BS in the same MBS_Zone will send multicast broadcast data synchronously, and use the same CID and SA to carry MBS data, which can form macro-diversity for participating MSs Effect. The mobile terminal obtains the MBS_Zone information from the broadcast information of the BS, and one BS can belong to multiple MBS_Zones at the same time. In the multi-BS access mode, in order to improve the receiving performance, macro-diversity can be adopted. This method requires that at the same time, BSs in the same MBS area use the same frequency, symbol, sub-channel, and modulation method to transmit the same data synchronously, which enables the mobile terminal to receive MBS data from multiple BSs at the same time, thus improving reception reliability and reception quality.

Because the aforementioned multicast broadcast service usually performs a single transmission. This will greatly affect the satisfaction of senders who fail to decode, especially those who fail to decode mobile streaming media. Moreover, there is no timely feedback information in the traditional multicast broadcast service, ARQ is not used, and a single transmission is usually performed. Since the multicast broadcast service is sent to multiple mobile terminals in the service area at the same time, in the case of a single transmission, the transmission rate of the multicast broadcast service is usually low in order to meet the reception of the sender with the worst channel state. As shown in Figure 1, Figure 1(a) is a schematic diagram of the operation of unicast services in a traditional cell. The transmitter near the base station of the cell can use the 16QAM adjustment coding method because the channel condition is good. However, the transmitting end relatively far away from the base station of the cell can only use an adjustment encoding method with a low transmission rate such as QPSK due to poor channel conditions. When performing multicast broadcast service transmission, as shown in Figure 1(b), assuming that the channel status of each sender is the same as that in Figure 1(a), in order to meet the reception requirements of all senders, the base station can only use the QPSK adjustment coding method , leading to a lower overall transmission rate of the system.

In fact, if the channel state information (CSI or CQI) of the sender to be received is not obtained, the base station (BS) does not know the situation of the sender with the worst channel state, and it usually assumes that the receiving condition of the sender with the worst channel state is very poor, and the signal interference The ratio is very low, such as at the edge of the cell, so the strongest modulation and coding method and higher power are used to transmit multicast broadcast service data, such as the QPSK method shown in Figure 1 (b). This not only directly leads to the decline of system spectrum efficiency, but also brings many negative effects. For example, it will cause interference to neighboring cells; it will reduce the broadband experience of the sender with a better channel state; it will increase the energy consumption of the terminal at the sender with a better channel state. At the same time, because it essentially prolongs the receiving and decoding time of the sending end with a better channel state, it will consume more energy consumption of its terminal. Therefore, in order to better support multicast and broadcast services, the desired modulation and coding state is shown in FIG. 2 . That is, the transmitter farther away from the base station receives multicast and broadcast data with low modulation order (such as QPSK) or low bit rate, while at the same time, the transmitter closer to the base station receives high modulation order (such as 16QAM) or high code rate rate multicast and broadcast data.

FIG. 3 is a schematic diagram of traditional ACK/NACK work. It can be seen that in multicast and broadcast services, if any sender fails to receive data correctly, the entire multicast and broadcast services will be affected. As shown in the figure, the sender MS3 fails to receive the data data2 correctly, which will cause the suspension of sending new data in the multicast and broadcast services, and the retransmission of the data data2. Such efficiency is obviously low and needs to be improved. In fact, with the increasing number of multicast services, the requirements of the terminal will also continue to increase, and it may receive two or more multicast broadcast services at the same time. However, most terminals are powered by batteries, and the battery power is limited. Therefore, how to effectively reduce terminal energy consumption is a matter of great concern. IEEE 802.16e proposes a sleep mode for energy consumption. When there is no data transmission between the base station and the terminal, the terminal can enter the sleep state, that is, to reduce energy consumption by turning off certain physical components (such as radio frequency modules). However, it is incomplete to reduce terminal energy consumption only by putting the terminal into a dormant state, because a large amount of energy consumption occurs during data transmission. Therefore, it is also very important to design a better MBS data transmission solution for a large number of multicast broadcast services in the future.

Contents of the invention

The object of the present invention is to provide a method for sending signals in a communication system.

According to an aspect of the present invention, a method for sending a signal by a communication system includes the steps of:

The sender simultaneously transmits signals on the shared wireless resources;

The receiving end counts the state of the sending end according to the signal received on the wireless resource.

According to another aspect of the present invention, an information detection method in a communication system includes the steps of:

At the receiving end, the signal received by at least one wireless resource is a vector sum of signals sent by multiple sending ends;

The receiving end judges the characteristics of the sending end according to the vector sum of the received signal.

The multicast broadcast service feedback channel method of the present invention can not only effectively collect channel state information of multiple sending ends, reduce false alarm and missed detection probability, but also save wireless channel resources compared with traditional feedback channel schemes.

Description of drawings

Fig. 1 is a schematic diagram of the modulation and coding state of a data service in a traditional cell, wherein (a) is a schematic diagram of a modulation and coding state of a unicast service in a traditional cell, and (b) is a schematic diagram of a modulation and coding state of a multicast/broadcast service in a traditional cell;

Fig. 2 is a schematic diagram of a new multicast/broadcast service modulation and coding state;

Figure 3 is a schematic diagram of traditional ACK/NACK work;

Fig. 4 is a schematic diagram of a new multicast broadcast service transmission state;

Figure 5 is a schematic diagram of the new transceiver signal;

Fig. 6 is a new multicast broadcast service feedback channel allocation and application schematic diagram 1 in the present invention;

Fig. 7 is a new multicast broadcast service feedback channel allocation and application schematic diagram II in the present invention;

Fig. 8 is a new multicast broadcast service feedback channel allocation and application schematic diagram 3 in the present invention;

Fig. 9 is a schematic diagram 4 of new multicast broadcast service feedback channel allocation and application in the present invention;

FIG. 10 is a schematic diagram of new multicast broadcast service feedback channel mapping and allocation;

Fig. 11 is a reception effect diagram of the new multicast broadcast service feedback channel.

Detailed ways

In order to provide more reliable transmission than the traditional multicast broadcast service in the multi-carrier mobile communication system, ensure the quality of service (Quality of Service, QoS) of most senders, and provide higher spectrum utilization, the present invention proposes a A method for sending signals in a mobile communication system. The method defines that in the uplink and/or downlink transmission links of the system, the receiver obtains the transmission status information of the multicast broadcast service in the system by receiving feedback information from multiple senders serving the multicast broadcast service, so as to facilitate corresponding Adjustment, such as the modulation order, whether retransmission is required, etc., so as to realize the adaptive transmission of multicast broadcast services, and improve the spectral efficiency of the system and the satisfaction of the sending end. The multicast broadcast service feedback channel scheme designed according to the present invention can not only effectively collect channel state information of multiple sending ends, reduce false alarm and missed detection probability, but also save wireless channel resources than traditional feedback channel schemes.

With the continuous improvement of the requirements of the sending end, more and more mobile streaming media services will be included in the future mobile communication services. With the extensive development of mobile streaming media services, a large number of multicast broadcast services will appear, and the frequency of their services will also increase rapidly. For popular multicast broadcast services, there may be hundreds or even thousands of MBS senders within the range of a BS. In this case, the optimization of the multicast broadcast service becomes very important. In the past, multicast broadcasting services usually performed a single transmission. If the decoding fails at the sending end, the corresponding information will be lost. According to the existing technology, if the sending end wants to receive the corresponding information lost just now again, it can only apply for another one, establish a point-to-point connection, and let the base station send the corresponding information to the sending end alone. Since there is no timely retransmission, this will greatly affect the experience of the sender who fails to decode when receiving mobile streaming data. And if the sender applies for another application, that is, when the first reception is not good or even interrupted at the sender, then apply for re-reception or viewing, and let the base station send the corresponding information to the sender again, which will not only consume a lot of wireless resources, And it will also greatly reduce the customer satisfaction of the mobile streaming media sending end.

In wireless communication, channels, sub-channels, code channels and sub-code channels, etc. all belong to wireless resources, so in this article, unless otherwise stated, the wireless resources mentioned can be used as channels, sub-channels, code channels and sub-code channels, etc. to replace.

Since there is no timely feedback information in the traditional multicast broadcast service, the system cannot provide timely retransmission, that is, methods such as Automatic Repeat Request (ARQ) cannot be used. Since the multicast broadcast service is sent to multiple mobile terminals in the service area at the same time, if the traditional channel feedback method is adopted, that is, each sender sends feedback information regardless of the channel status, which will definitely occupy a large amount of time. uplink resources. However, if only the sender with poor channel state sends the channel state information, a lot of resources will be saved. For example, conventional feedback information usually includes correct reception, namely ACK, and incorrect reception, namely NACK. Only the sending end that needs to send NACK information sends information, which will inevitably save a lot of resources.

Another way to save resources is partial sending, which can also be called proportional sending. If there are N senders who want to send their channel state information, the system can set a principle so that there are less than N senders that meet this sending principle, assuming M (M and N are positive integers, and M is not greater than N) , that is, the number of sending ends that actually send channel state information is M, which realizes partial sending and achieves the purpose of saving resources. After the system receives the information sent by M senders, it can deduce the relevant information of N senders from the information sent by M senders according to the principles set by the system, so it can get the information that is actually sent by N senders. The result is similar to the information sent by the end. Since the number of sending ends that actually send information and occupy channel resources is only M, a lot of resources can be saved. A simple and effective implementation of the above method is proportional selection, that is, each of the N senders sends information according to the probability of M/N (M/N is less than 1), so that the number of senders who finally send information is statistically reach M. Another method is to select according to the unique code corresponding to the sending end. For example, when the code is a binary value, such as a connection identifier (CID), only the n and o bits of the code (n and o are positive integers and not equal) It is the sending end of "0" and "1" to send, so basically 4 out of 1 is realized. A weakness of the partial sending method is that, due to the use of statistical principles, the results are only accurate when the number of senders is large.

In short, in the above two methods, when transmitting information, the number of sending ends is smaller than the number of sending ends satisfying the original trigger condition. That is to say, in the traditional automatic repeat request (Automatic Repeat Request, ARQ) transmission method, after the sender receives a data packet, it will trigger sending ACK or NACK information according to whether it is received correctly, that is, the original trigger condition is in Receive data and decode it, whether it is received correctly or not, it will be sent due to the original trigger condition of sending ACK or NACK information. Apparently, only the sending end sending NACK information will make the number of sending ends smaller than the number of sending ends satisfying the aforementioned original trigger condition. For the partial sending method, the number M of sending ends will obviously be smaller than the number N of sending ends satisfying the original trigger condition.

In addition, the existing methods for providing feedback information are all point-to-point, especially for the uplink, usually requiring a single sender to provide its channel state information, which is received by the base station, and the base station can clearly know that this is Channel state information of a sender. Although this feedback method is accurate, it also has obvious disadvantages, that is, it occupies a large amount of radio link resources. Because it is necessary to distinguish the channel state information of these sending ends, it is necessary to make these information as orthogonal as possible in the uplink to avoid collisions as much as possible. Therefore, if there are N transmitters sending their channel state information, the system should allocate N mutually orthogonal wireless resources, that is, allocate N mutually orthogonal channels, sub-channels, code channels or sub-code channels . The allocation of these wireless resources can be one of the three commonly used orthogonal allocation methods, namely frequency division, time division or code division, or a combination of these three orthogonal allocation methods, such as time division The frequency division method is another example of the time division method plus the frequency division method and the code division method. In a multi-carrier communication system, the OFDM symbol is usually used as the basic allocation unit in the time division method, the subcarrier is usually used as the basic allocation unit in the frequency division method, and an orthogonal sequence is usually used as the basic allocation unit in the code division method. In order to save resources and improve spectrum utilization, the present invention proposes a feedback method, that is, by allowing different sending ends to overlap each other when sending feedback information, the number of mutually orthogonal wireless resources that need to be provided in the uplink is reduced, It also saves radio link resources. Allowing different senders to overlap each other when sending feedback information, that is, allowing different senders to send feedback information in the same wireless resource, may make it impossible for the system to distinguish which sender the received information comes from. However, for multicast broadcast services, this is not a problem that cannot be ignored. Because the system is sending to multiple mobile terminals in the service area at the same time, it does not need to obtain the channel state information of a specific sender, but the key is to obtain the channel state information of these mobile terminals receiving multicast broadcast services in the service area Statistical information in order to determine the next transmission method. On the other hand, in order to prevent the broadband experience of most senders from being greatly reduced due to the fact that the multicast broadcast service needs to satisfy individual senders with poor channel conditions, the multicast broadcast service should consider the needs of most senders rather than individual senders. terminal needs. In order to satisfy the reception of individual senders with poor channel conditions, the transmission rate of the multicast broadcast service must be very low, which will definitely lead to low overall operation efficiency of the multicast broadcast service. Therefore, the multicast broadcast service can meet the needs of most senders while considering the needs of individual senders, and formulate some special mechanisms to try to meet the needs of individual senders with poor channel conditions, so that the overall operating efficiency of the multicast broadcast service can be maintained. at a high level. Based on the needs of individual senders with poor channel conditions, there can be many special mechanisms formulated. For example, another time or channel is agreed, and these individual senders will send separately when the channel status of these individual senders improves. Therefore, the feedback method proposed by the present invention is to collect the demand or channel state information of multiple senders in the multicast broadcast service and make statistics without distinguishing each sender from the received feedback information. In fact, this belongs to the method of using a shared channel for transmission.

It is beneficial to obtain channel state statistical information when the sending end overlaps each other when sending feedback information. Since different mobile terminals can transmit information in the same wireless resource, at the receiving end, the received signal may be the sum of signals sent by multiple mobile terminals, which itself has a statistical effect. As shown in Figure 5, under ideal conditions, when no sender sends information at wireless resource 1, indicated by a dotted line, the receiver cannot receive information here, that is, the signal strength is zero; when there is 1 sender , that is, the sending end 3 sends information at the wireless resource 3, and the signal strength sent is 1 unit, which is represented by a square with a slash in the figure, and the receiving end can receive information here, and the signal strength is 1 unit; similarly, when there are 2 senders sending information at wireless resource 2, and the signal strength sent by each sender is 1 unit, then the receiver can receive the information here, and the signal strength is about 2 units, that is, the signal strength is about twice the signal strength received at wireless resource 3; when there are 3 senders sending information at wireless resource 4, the signal strength sent by each sender is 1 unit, Then the receiving end can receive information here, and the signal strength is about 3 units, that is, the signal strength is about 3 times the signal strength received at wireless resource 3; and so on, when there are N sending ends at the same time When sending information at a certain wireless resource, the receiving end will receive the information here, and the signal strength is about N units. In consideration of saving resources, a wireless resource in FIG. 5 can generally be understood as a small information transmission unit in a wireless transmission link, even the smallest information transmission unit, for example, a subchannel or a subcode channel. In addition, FIG. 5 is a schematic diagram, which considers an ideal situation and does not introduce signal fading in an actual wireless transmission system, but this will not affect the understanding of the present invention by ordinary engineers and technicians in the art. In fact, each sending end needs to adjust its own transmission power so that the signal strength of the signal transmitted by itself when it reaches the receiving end after attenuation is as equal as possible to that of other sending ends, that is, the strength is 1 unit.

Under ideal conditions, we hope that when there are N transmitters sending information at a certain wireless resource at the same time, the signal strength received by the receiver is about N units, that is, the algebraic sum of the signal strengths. However, the signal strength received by the receiving end is usually not the algebraic sum of the strengths of the signals sent by the sending ends when they reach the receiving end. In the actual system, due to the fading of the wireless channel, we not only need to consider the signal strength, but also the vector angle of the signal, that is to say, the wireless signal should be regarded as a complex number, that is, a two-dimensional vector. Therefore, within a wireless resource, the received signal should correspond to the vector sum of the signals at each sending end when they arrive at the receiving end. As shown in Figure 4, assuming that mobile terminals TA1 and TC1 transmit information in the same wireless resource, due to fading, when the signal reaches the receiving end, the amplitude and angle both change, as shown in the figure, signals A1 and C1 respectively , then the actually received signal is R1. It can be seen that R1 is the vector sum of vectors A1 and C1. Obviously, based on the knowledge of vector summation, we can know that the magnitude of vector R1 will be less than or equal to the sum of the magnitudes of vector A1 and vector C1, that is, the actual received signal strength will be less than or equal to the two sending ends. The algebraic sum of the strengths of the signal when it reaches the receiver. In addition, when the feedback information of different sending ends is superimposed at the receiving end, mutual weakening may occur. For example, in Figure 4, signal A1 and signal A2 have the same amplitude but opposite angles, so their vector sum is zero, which means that no feedback signal is received at the receiving end. There is another kind of situation, that is, the vectors C1 and C2 do not cancel each other, but the vector sum of the three vectors C1, C2 and C3 is close to zero, that is, there is a phenomenon of mutual cancellation among multiple vectors. Obviously, this mutual cancellation will have a great negative impact on the detection of the feedback signal. For example, when it is desired to detect the number of transmitters that transmit signals simultaneously in a wireless resource, M vectors that cancel each other will mean less calculation of M transmitters, because it is difficult to be detected after mutual cancellation.

In order to avoid the occurrence of the above detection errors, the present invention proposes a brand new feedback method. In order to effectively collect channel state information of multiple senders, one or more feedback channels may be configured for each multicast broadcast service. Wherein, each feedback channel is composed of several feedback sub-channels. These feedback sub-channels may overlap each other, but any two feedback sub-channels will not overlap completely. This can greatly reduce the phenomenon that signals at the sending end cancel each other out. From the perspective of wireless resources, the feedback channel is composed of I (I is a positive integer) wireless resources, and the feedback sub-channel is composed of J (J is a positive integer, and J is less than I) wireless resources. J is variable within a feedback channel. For example, some feedback subchannels consist of J' (J'=2) radio resources, while in the same feedback channel, some feedback subchannels may consist of J'+ 2, J'+1, J'-1, or J'-2 radio resources. For a specific sending end, when sending feedback information, first select a feedback sub-channel in a feedback channel, and then send feedback information at all radio resources corresponding to the feedback sub-channel. The feedback information sent by the sending end at each radio resource may be the same or different, which will not affect the implementation of the present invention. For example, a sender can send information "+1" at each radio resource of a feedback subchannel, or send information "+1-j" at one radio resource, and send information "-j" at another radio resource. 1+j". Obviously, as mentioned above, the system may not need to identify whether the information it sends is "+1" or "-1".

The aforementioned wireless resources constituting the feedback channel in the present invention can be regarded as the information transmission unit during feedback transmission, or even the minimum information transmission unit. There are many specific implementations, and Fig. 10 is only one of them. Usually, the information transmission unit of a multi-carrier communication system consists of one to several time-frequency cells. The size of each time-frequency cell is the same, and it usually occupies one physical subcarrier in the time domain and one OFDM symbol in the frequency domain. Regarding code channels and sub-code channels, people are most familiar with the orthogonal code channels in CDMA systems, such as the code channels in the US IS-95 standard specification. Simply put, each of its orthogonal walsh code sequences will correspond to a Orthogonal code track. In fact, a similar code channel concept can also be realized in a multi-carrier communication system, which can be accomplished by transmitting a set of orthogonal Walsh code sequences in several time-frequency unit cells. For example, in FIG. 10 , each small square represents a time-frequency cell, the horizontal axis represents time, and the vertical axis represents subcarriers, that is, as shown in FIG. 10 , there are 6 OFDM symbols and 18 subcarriers. Then, if an orthogonal Walsh code sequence with a length of 4 is transmitted in the 4 time-frequency cells marked "1", this code sequence will correspond to an orthogonal code channel. Because in the orthogonal space, there are 4 orthogonal Walsh code sequences with a length of 4, so this group of orthogonal Walsh code sequences has at most 4 orthogonal sequences, that is, the four time-frequency units marked "1" can be Four orthogonal code tracks are set up in the grid. Therefore, in a multi-carrier communication system, the minimum information transmission unit can usually be a time-frequency unit cell, or a code channel or a sub-code channel based on several time-frequency unit cells. In the wireless propagation environment, due to the existence of time variation and frequency domain fading, for the information sent by the same transmitter, the channel variation between the time-frequency cells that are closer in the time domain and frequency domain will obviously be smaller than the relative distance The channel variation between the time-frequency cells. However, since the present invention focuses on obtaining the information of the sending end through statistical characteristics, the distance between the time-frequency cells will not have a great impact on the implementation of the present invention. That is to say, there is no restriction on the distance between the time-frequency cells of the wireless resources constituting the feedback channel. In addition, in the implementation of the present invention, resource mapping and allocation are not limited to 6 OFDM symbols and 18 subcarriers in FIG. 10 , but can be any number of OFDM symbols and subcarriers.

It can be seen from the following embodiments that the feedback channel and feedback subchannel configuration scheme of the present invention can reduce the probability of missed detection. Compared with the traditional feedback method, the new multicast broadcast service feedback channel allocation method in the present invention can greatly eliminate the influence of signals canceling each other between sending ends, so that the statistical characteristics of the signal are more accurate. As shown in FIG. 11 , it can be seen that the reception effect of the new multicast broadcast service feedback channel has smaller variance. Therefore, the estimation of the statistical characteristics of the invention will be more stable and accurate, and the more the number of sending ends, the more obvious the advantages of the method.

Those skilled in the art should easily understand that the present invention can be applied to uplink channels and downlink channels in communication systems. According to the same principle or idea, it can be applied to any scenario where multiple senders share channel resources for information transmission, and is not limited to multi-carrier communication systems or wireless communication systems. Its application scenarios are not limited to the situation of resending data, but can be extended to multiple senders performing information transmission on shared channel resources, and can be applied to the system to count the status of senders, for example, the ratio of support or rejection. By using the present invention, the number of sending ends satisfying the trigger condition is used as the denominator, and the number of sending ends determined by the receiving end according to the received signal vector and judgment is used as the numerator, and the support or negative ratio of the sending end can be obtained. In addition, the number of channel resources constituting the feedback channel in the present invention, that is, the I value and the J value, is not limited to the numbers in the following embodiments, and may be any positive integer. In fact, the present invention is mainly aimed at the following application scenarios, that is, the sending end shares channel resources for transmission, and when the receiving end performs detection, it focuses on statistical characteristics, such as the number of sending ends, etc., and does not need to know each sending end information transmitted.

The tables in Figures 6, 7, 8 and 9 use the same coordinate representation to describe the allocation and application of the new multicast broadcast service feedback channel. The numbers in the table represent the different senders.

Example 1

As shown in FIG. 6 , the horizontal axis represents different wireless resources, and the vertical axis reflects the situation that the feedback information of the sending end is superimposed at the receiving end, and different numbers in the figure represent different sending ends. It can be seen from FIG. 6 that the feedback channel is composed of I (I=4) wireless resources, and there are 6 feedback sub-channels, each composed of J (J=2) wireless resources. The six feedback sub-channels are composed of radio resources 1 and 2, 1 and 3, 2 and 3, 2 and 4, 4 and 3, and 4 and 1 respectively. For example, the sending end "1" occupies a feedback subchannel, which consists of radio resources 1 and 2, and the feedback subchannel occupied by the sending end "10" consists of radio resources 4 and 1. If the sending end 1 and the sending end 10 cancel each other at the wireless resource 1, they will be detected at the wireless resource 2 and the wireless resource 4 respectively because they transmit feedback information in different feedback sub-channels. As another example, the transmitters 1, 8, and 10 cancel each other at wireless resource 1. Similarly, since they transmit feedback information in different feedback sub-channels, they will be detected at wireless resources 2, 3, and 4, respectively. come out. Therefore, the probability of missed detection can be reduced through the feedback channel and feedback sub-channel configuration scheme of the present invention.

Example 2

As shown in FIG. 7 , the feedback channel consists of I (I=5) radio resources, and J is equal to 2 or 3. There are 12 feedback sub-channels, 6 of which are composed of 2 wireless resources, and these 6 feedback sub-channels are respectively composed of wireless resources 1 and 2, 1 and 3, 2 and 3, 2 and 4, 4 and 3, 4 and 1 constitute. The other 6 are composed of 3 wireless resources, and these 6 feedback subchannels are respectively composed of wireless resources 1, 5 and 2, 1, 5 and 3, 2, 5 and 3, 2, 5 and 4, 4, 5 and 3, 4, 5 and 1 form. For example, the feedback subchannel occupied by the transmitting end "1" is composed of wireless resources 1, 5 and 2, and the feedback subchannel occupied by the transmitting end "8" is composed of wireless resources 1 and 3.

Example 3

As shown in Figure 8. The feedback channel is composed of I (I=3) wireless resources, and there are 3 feedback sub-channels, each composed of J (J=2) wireless resources. The three feedback subchannels are composed of radio resources 1 and 2, 1 and 3, and 2 and 3, respectively.

Example 4

As shown in FIG. 9 , the feedback channel consists of I (I=5) radio resources, and J is equal to 2 or 3. There are 12 feedback sub-channels, 6 of which are composed of 2 wireless resources, and these 6 feedback sub-channels are respectively composed of wireless resources 1 and 2, 1 and 3, 2 and 3, 2 and 4, 4 and 3, 4 and 1 constitute. The other 6 are composed of 3 wireless resources, and these 6 feedback subchannels are respectively composed of wireless resources 1, 5 and 2, 1, 5 and 3, 2, 5 and 3, 2, 5 and 4, 4, 5 and 3, 4, 5 and 1 form. In this application, the feedback subchannel occupied by the sending end "1" is composed of wireless resources 1 and 2, and the feedback subchannel occupied by the sending end "2" is composed of wireless resources 1, 3 and 5.

Example 5

Fig. 10 illustrates an implementation situation of mapping and allocation of a new multicast broadcast service feedback channel. As shown in Figure 10, each small square represents a time-frequency cell, the horizontal axis represents time, and the vertical axis represents subcarriers, so Figure 10 contains 6 OFDM symbols and 18 subcarriers. As mentioned above, we can set up 4 orthogonal code channels in the 4 time-frequency cells marked "1", which are respectively called W11, W12, W13 and W14. Next, four orthogonal code channels can be set up in the four time-frequency unit cells marked "2", which are called W21, W22, W23 and W24 respectively. By analogy, 4 orthogonal code channels can be set up in 4 time-frequency cells marked as "m" (m is a positive integer), which are called Wm1, Wm2, Wm3 and Wm4 (also can be expressed as W _{m, 4} ). As mentioned above, although the distance between the time-frequency cells of several wireless resources constituting the feedback subchannel is not limited, in practical applications, it is recommended to use wireless resources with relatively short distances. Therefore, when a feedback channel needs to be composed of 4 wireless resources, it is recommended to select wireless resources that are very close to each other, such as W _1,1 , W _1,2 , W _1,3 and W _1,4 , of course it is also possible Select wireless resources that are far away from each other, such as W _11,1 , W _12,2 , W _13,1 and W _14,4 . Similarly, when a feedback channel needs to be composed of 5 wireless resources, it is recommended to select wireless resources that are very close to each other, such as W _12,1 , W _12,2 , W _12,3 , W _12,4 and W _{13 , 3} , of course, you can also choose wireless resources that are far away from each other, such as W _21,1 , W _31,2 , W _13,3 , W _24,3 and W _41,4 , or W _31,1 , W _32,2 , W _33,3 , W _34,3 and W _35,4 .

Example 6

Referring to FIG. 10, one feedback channel is constituted by four radio resources. Wireless resources 1, 2, 3 and 4 respectively correspond to the 4 time-frequency cells marked as "m" (m is a positive integer) in FIG. 10 , such as the 4 time-frequency cells marked as "1". In this embodiment, no orthogonal code channel is established therein.

Example 7

Referring to FIG. 10 and Embodiment 6, a feedback channel is formed by 20 radio resources. Wireless resources 1, 2, 3, and 4 correspond to the four time-frequency units marked "1" in Figure 10, and wireless resources 5 to 8 correspond to the four time-frequency units marked "2" in Figure 10 Cells, wireless resources 9 to 12 correspond to the four time-frequency cells marked "3" in Figure 10, and wireless resources 13 to 16 correspond to the four time-frequency cells marked "4" in Figure 10, The radio resources 17 to 18 respectively correspond to the four time-frequency cells marked as "5" in FIG. 10 . In this embodiment, no orthogonal code channel is established therein.

Example 8

Referring to FIG. 10 and Embodiment 5, three wireless resources W _13,4 , W _22,2 and W _42,1 form a feedback channel. There are three feedback sub-channels, which are composed of wireless resources W _13,4 and W _22,2 , W _13,4 and W _42,1 , W _22,2 and W _42,1 respectively. It can be seen that the three wireless resources are relatively far apart in the time-frequency domain, which can also be applied to the present invention.

Claims (14)

1. A method for a communication system to send a signal, comprising the steps of: The sender simultaneously transmits signals on the shared wireless resources; The receiving end counts the state of the sending end according to the signal received on the wireless resource. 2. The method according to claim 1, characterized in that the sending end only includes the sending end receiving incorrectly. 3. The method according to claim 1, characterized in that the multiple sub-channels formed by the wireless resources overlap with each other. 4. The method as claimed in claim 3, characterized in that the number of radio resources forming different subchannels is different. 5. The method according to claim 1, characterized in that the number of senders transmitting information on the shared channel is less than the number of senders satisfying the original trigger condition. 6. The method according to claim 3, characterized in that the information transmitted by a transmitting end on each radio resource of the sub-channel is the same. 7. The method of claim 1, wherein the sender status includes a support or a negative ratio. 8. The method according to claim 1, characterized in that the distance between the wireless resources in the time-frequency domain is kept as small as possible. 9. An information detection method in a communication system, comprising the steps of: At the receiving end, the signal received by at least one wireless resource is a vector sum of signals sent by multiple sending ends; The receiving end judges the characteristics of the sending end according to the vector sum of the received signal. 10. The method according to claim 9, characterized in that the feedback channel formed by the wireless resources includes a plurality of feedback sub-channels. 11. The method according to claim 10, characterized in that the feedback sub-channels overlap each other. 12. The method according to claim 10, characterized in that any two feedback sub-channels do not completely overlap. 13. The method of claim 9, wherein the characteristic of the sender includes the number of senders. 14. The method according to claim 9, characterized in that the number of senders sending signals is smaller than the number of senders satisfying the original trigger condition.

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