Disclosure of Invention
The invention aims to provide a method and a device for realizing information transmission in a wireless communication system, thereby realizing the transmission of single-bit information of a CDMA user based on an OFDM technology in the wireless communication system and being convenient for realizing the effective control and management of services in the wireless communication system.
The purpose of the invention is realized by the following technical scheme:
the invention provides a method for realizing information transfer in a wireless communication system, which comprises the following steps:
in an orthogonal frequency division multiplexing OFDM communication system with a CDMA service channel in a reverse channel, single-bit information to be sent in a forward control channel is subjected to expansion and scrambling processing, and an information sequence obtained by processing comprises user information;
and carrying out Orthogonal Frequency Division Multiplexing (OFDM) modulation processing on the information sequence obtained by processing, and transmitting the information sequence through an antenna.
The expanding and scrambling process specifically includes:
carrying out expansion operation on the single-bit information to obtain a plurality of corresponding bits, and then carrying out scrambling processing on the plurality of bits by using user information to obtain an information sequence of the user;
or,
using user information to simultaneously carry out expansion and scrambling processing on the single-bit information to obtain an information sequence of the user;
or,
and spreading and scrambling the single-bit information by adopting orthogonal codes and scrambling codes related to the user to obtain an information sequence of the user.
In the present invention, the expanding operation on the single-bit information specifically includes: and the single-bit information is spread into a plurality of bits by using an orthogonal code or direct repetition.
The spreading and scrambling by using the orthogonal code and the scrambling code related to the user specifically comprises the following steps:
mapping part of bits in the user information into different orthogonal codes, and performing expansion operation on single-bit information of different users to obtain a plurality of corresponding bits; then mapping the residual bits in the user information into different scrambling codes, scrambling the corresponding bits of different users, and adding the information sequences scrambled by the different scrambling codes to obtain the information sequence of the user;
or,
mapping partial bits in user information into different orthogonal codes, and performing expansion operation on single-bit information of different users to obtain a plurality of corresponding bits; then, mapping the rest bits in the user information into different scrambling codes, adding the bits of different users mapped into the same scrambling code, scrambling by the scrambling codes after adding, and adding the information sequences scrambled by different scrambling codes to obtain the information sequence of the user.
The orthogonal codes include, but are not limited to Walsh codes or discrete fourier transform DFT codes.
The OFDM modulation processing on the information sequence obtained by the processing specifically includes:
and mapping the information sequence to a discrete resource channel DRCH or a block resource channel BRCH of an orthogonal frequency division multiple access OFDMA system, and carrying out OFDM modulation processing.
In the present invention, before performing the OFDM modulation process, the method further includes:
and adding the information sequences of the plurality of users, and taking the added information sequences of the plurality of users as the information sequences needing OFDM modulation processing.
The user information comprises: MACID (media access control identification of the user), or user sequence number, or user group number.
The single-bit information of the user comprises: acknowledgement F-ACK information for the user and/or power control F-PCB information for the user.
In the present invention, if the single-bit information of the user includes F-ACK information and F-PCB information, the process of performing the expansion and scrambling by using the user information further includes a process of distinguishing the F-ACK information from the F-PCB information, which specifically includes:
compounding the F-ACK information and the F-PCB information as an I path signal and a Q path signal respectively;
or,
spreading the F-ACK information and the power control F-PCB information by adopting different orthogonal codes respectively;
or,
and respectively mapping information sequences obtained after the F-ACK information and the power control F-PCB information are spread and scrambled to different physical channel resources.
The method further comprises the following steps:
classifying F-ACKs and/or F-PCBs to be sent, which belong to different mobile terminals, into a plurality of groups according to channel quality or sending power;
and different transmission power is adopted for transmitting the information to be transmitted of each group.
The processing divided into a plurality of groups specifically includes:
sorting F-ACKs and/or F-PCBs belonging to different mobile terminals according to channel quality or transmission power, and grouping the sorted information according to the sequence;
or classifying according to different packet formats PF of the terminal to which the F-ACK and/or the F-PCB belong, and selectively dividing the corresponding F-ACK and/or the F-PCB into different groups.
The processing for transmitting by using different transmission powers includes:
mapping each group of information to be transmitted to physical channel resources in an orthogonal multiplexing mode, and transmitting with different transmission power.
The processing for transmitting by using different transmission powers includes:
adding the scrambled information sequences corresponding to different users in each group, multiplying the result by the power gain coefficient of each group, mapping to the physical channel resource in an orthogonal multiplexing mode, and transmitting.
The orthogonal multiplexing mode comprises the following steps: frequency division multiplexing, time division multiplexing or time-frequency hybrid multiplexing.
The invention provides a device for realizing information transmission in a wireless communication system, which is applied to an OFDM communication system with a reverse channel having a CDMA service channel, and comprises:
the single bit information spreading and scrambling processing unit is used for spreading the single bit information of the user to be sent and scrambling the single bit information by utilizing the user information;
and the information sending processing unit is used for carrying out OFDM modulation processing on the information sequence obtained by the single-bit information spreading and scrambling processing unit and sending the information sequence through an antenna.
The single-bit information spreading scrambling processing unit specifically includes: an extension processing unit and a scrambling processing unit, or a scrambling extension processing unit, wherein:
the extension processing unit is used for carrying out extension operation on the single-bit information to obtain a plurality of corresponding bits;
a scrambling processing unit for scrambling the plurality of bits obtained by the spreading processing unit by using the user information to obtain the information sequence of the user;
or,
and the scrambling and spreading processing unit is used for spreading and scrambling the single-bit information by using the scrambling code of the user information to acquire the information sequence of the user.
The information sending and processing unit comprises:
the mapping processing unit maps the information sequence to a discrete resource channel or a block resource channel of an Orthogonal Frequency Division Multiple Access (OFDMA) system;
and the modulation sending processing unit is used for carrying out OFDM modulation processing on the information sequence, transmitting the information sequence to an antenna and sending the information sequence through the antenna.
The information sending processing unit also comprises a multi-user processing unit which is used for adding the information sequences of a plurality of users and transmitting the information sequences of the plurality of users obtained after the addition to the modulation sending processing unit.
The user information comprises: the media access control identification MACID of the user, or the user serial number, or the user group number;
the single-bit information of the user comprises: acknowledgement F-ACK information for the user and/or power control F-PCB information for the user.
It can be seen from the above technical solutions that the present invention mainly expands the original channel for transmitting single-bit information, such as F-ACK channel, F-PCB channel, etc., so that the channel can support both OFDM service and CDMA service.
Moreover, the invention adopts orthogonal code related to MACID or/and scrambling code expansion and scrambling to send corresponding single-bit information, so that a receiving end (such as a mobile terminal) can determine the scrambling code and the spreading code only through the MACID information distributed to the receiving end, thereby demodulating the single-bit information corresponding to the terminal, such as F-ACK information and/or F-PCB information.
Therefore, the realization of the invention can greatly reduce the control signaling and the scheduling complexity of the CDMA service of the AIE system.
Detailed Description
The invention mainly expands the current channel for transmitting the single-bit information, so that the expanded channel can transmit the single-bit information of the user in the network of the OFDM transmission technology.
For example, the invention expands the current F-ACK channel and F-PCB channel, so that the expanded F-ACK channel can transmit response information for OFDMA users, and can transmit response information for users; similarly, the expanded F-PCB channel may provide power control information for OFDMA users, and may also provide power control information for users at the same time
The following will describe in detail a specific implementation of the present invention by taking the transmission of F-ACK and/or F-PCB information of a user as an example.
The invention provides an improved implementation scheme of a forward control channel of a CDMA service channel under a wireless mobile communication OFDM system, wherein the control channel comprises: F-ACK (forward acknowledgement), F-PCB (forward power control) information.
In the improved implementation scheme, F-ACK bits of each path of users are firstly subjected to on-off keying modulation to generate F-ACK symbols, wherein "+ 1" represents a positive acknowledgement, and the blank represents a negative acknowledgement; the F-PCB bits of each user are first BPSK modulated, where "+ 1" indicates power up and "-1" indicates power down.
After determining the corresponding F-ACK symbol and/or F-PCB symbol, the network side (such as a base station) converts the F-ACK bit and/or F-PCB bit to be sent into single-bit F-ACK or F-PCB information into N-bit information through an orthogonal code or a direct repeated expansion mode; for the information code sequence obtained after spreading, scrambling the information code sequence by adopting a scrambling code related to MACID to obtain information sequences (namely symbol sequences) of different users; then, the sequences of different users are added and mapped to an OFDMA (Orthogonal Frequency Division multiple Access) system DRCH (distributed resource channel) or BRCH (block resource channel); and finally, carrying out OFDM modulation processing on an information sequence obtained by the single-bit information, and sending out the information sequence through an antenna. The orthogonal codes include Walsh codes, DFT (discrete fourier transform) codes, and the like.
In the implementation scheme provided by the invention, the sending and processing mode of the F-ACK information bit and the F-PCB bit of the same user can specifically select any one of the following modes:
(1) can be mapped into mutually orthogonal code sequences during spreading and then added and multiplexed together;
(2) after expansion, the signals are respectively mapped to an I path and a Q path and are added and multiplexed together.
(3) After scrambling, the resource blocks mapped to different OFDM physical channels are multiplexed together.
Moreover, in the implementation scheme provided by the present invention, the scrambling code related to the MACID may be generated for all bits passing through the MACID, or may be generated for some bits passing through the MACID.
The same channel (e.g., F-ACK channel or F-PCB channel) for different users with different MACIDs may be spread by the same code, or may be spread by different orthogonal codes. The same channels of different users can be divided into two groups, and are respectively transmitted through an I path and a Q path.
The specific implementation structure of the apparatus for implementing information transfer in a wireless communication system according to the present invention is shown in fig. 2, and mainly includes the following processing units:
(1) the single bit information spreading and scrambling processing unit is used for spreading the single bit information of the user to be sent and scrambling the single bit information by utilizing the user information;
the user information comprises: the media access control identification MACID of the user;
the single-bit information of the user comprises: the user's reply F-ACK information and/or the user's F-PCB information.
The users in the present invention may be CDMA users, or may also be OFDMA users.
In the apparatus, the single-bit information expansion scrambling processing unit may specifically adopt different implementation manners, for example, the single-bit information expansion scrambling processing unit may specifically include an expansion processing unit and a scrambling processing unit, or only include a scrambling expansion processing unit, and a specific implementation structure of each unit is as follows:
the extension processing unit is used for carrying out extension operation on the single-bit information to obtain a plurality of corresponding bits;
a scrambling processing unit, which uses the user information to scramble the multiple bits obtained by the spreading processing unit to obtain the information sequence of the user, such as the information sequence corresponding to the F-ACK information, or the information sequence corresponding to the F-PCB information, or the information sequence corresponding to the F-ACK and F-PCB information;
and the scrambling and expanding processing unit is used for expanding and scrambling the single-bit information by using the scrambling code of the user information, namely directly scrambling the single-bit information by using the MACID of the user and realizing the expanding operation aiming at the single-bit information, so that an information sequence of the user, such as an information sequence corresponding to the F-ACK information, or an information sequence corresponding to the F-PCB information, or an information sequence corresponding to the F-ACK information and the F-PCB information, can be obtained.
(2) The information sending processing unit is used for carrying out OFDM modulation processing on the information sequence obtained by the single-bit information spreading and scrambling processing unit and sending the information sequence through an antenna;
in the apparatus, the information sending and processing unit may specifically include:
a mapping processing unit, which maps the information sequence to a physical channel of the OFDMA system, such as a discrete resource channel or a block resource channel;
the modulation sending processing unit is used for carrying out OFDM modulation processing on the information sequence, transmitting the information sequence to an antenna and sending the information sequence through the antenna;
it should be noted that the information sending processing unit may further include a multi-user processing unit, configured to add information sequences of multiple users, and transmit the information sequences of the multiple users obtained after the addition to the modulation sending processing unit; the unit is arranged to transmit single-bit information of a plurality of users, such as F-ACK or F-PCB information, at the same time.
Several embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
Example one
The specific implementation of this embodiment is shown in fig. 3, and the corresponding processing procedure includes:
after F-ACK information and F-PCB information to be transmitted are determined, the F-ACK information bits are spread through Walsh code1(Walsh code 1), and the F-PCB information bits are spread through Walsh code2(Walsh code 2). Wherein the multiplication in the figure represents a dot multiplication for performing a dot multiplication operation on the Walsh code and the corresponding information.
After two expanded information bit sequences are obtained through dot multiplication, the two expanded information bit sequences are added through a SUM (SUM) unit, the added result is scrambled through a scrambling code related to MACID (namely, a scrambling code sc1.. n in the figure, wherein SC (scrambling code)) and users with different MACIDs can use different scrambling codes to scramble, namely, all bits of MACID are adopted to generate the scrambling codes.
The information sequences of all users obtained after scrambling are added, and the added information sequences are mapped to physical channel resources (such as DRCH or BRCH) in one physical frame.
And finally, carrying out OFDM modulation on each OFDM symbol in the physical frame to obtain a time domain signal, and sending out the time domain signal through an antenna.
Example two
The specific implementation structure of this embodiment is shown in fig. 4, and the corresponding processing procedure includes:
spreading the F-ACK channel and the F-PCB channel by spreading codes, namely spreading the F-ACK channel and the F-PCB information, specifically, performing corresponding dot product spreading operation by using the same Walsh code;
the expanded F-ACK information and the expanded F-PCB information are respectively taken as an I path signal and a Q path signal to be compounded (namely, the signals are added through an SUM unit) together;
scrambling the compounded signal by using the scrambling code of the MACID of the user, and adding the scrambled information of a plurality of users;
performing channel resource mapping, OFDM modulation and other processing on the signals which are obtained after the addition and contain the F-ACK information and the F-PCB information of a plurality of users, wherein the specific mapping and modulation processing mode is the same as the processing mode in the figure 3; and sending the signal subjected to mapping and modulation processing through an antenna.
In this embodiment, the spreading codes for the F-ACK channel and the F-PCB channel may or may not be the same. The spreading codes for the F-ACK channel and the F-PCB channel may be orthogonal codes, random codes, or arbitrary codes.
EXAMPLE III
The specific implementation structure of this embodiment is shown in fig. 5, and the corresponding processing procedure includes:
compounding (i.e. adding) the F-ACK information bits and the F-PCB information bits as an I path signal and a Q path signal respectively to obtain an information sequence comprising F-ACK information and F-PCB information;
then, expanding the information sequence through the scrambling code related to the MACID;
adding the expanded information sequences corresponding to the users;
and mapping the channel resources of the added information sequence to a physical channel, carrying out OFDM modulation and other processing, and then sending corresponding F-ACK and F-PCB information through an antenna.
Example four
In this embodiment, a specific description is given of a processing implementation scheme for delivering F-ACK information or F-PCB information of a user, respectively, as shown in fig. 6 and 7.
In fig. 6, specifically, the F-ACK information bits are transmitted separately by using the scheme provided by the present invention, and the corresponding processing procedure includes:
spreading the F-ACK information bits by adopting a Walsh code to obtain a plurality of bit information;
then, scrambling the bit information by adopting a scrambling code corresponding to the MACID so that a receiving end can determine a receiving user corresponding to the F-ACK information;
and sequentially adding the information sequences of the users after scrambling, mapping the information sequences to a physical channel, modulating the OFDM, and transmitting the information sequences containing the F-ACK information through an antenna.
In fig. 7, specifically, the scheme provided by the present invention is used for transmitting the F-PCB information bits separately, and the corresponding processing procedure includes:
spreading the F-PCB information bits by adopting a Walsh code to obtain a plurality of bit information;
then, scrambling the bit information by adopting a scrambling code corresponding to the MACID so that a receiving end can determine a receiving user corresponding to the F-PCB information;
and sequentially adding the information sequences of the users after scrambling, mapping the information sequences to a physical channel, modulating the OFDM, and transmitting the information sequences containing the F-PCB information through an antenna.
EXAMPLE five
In this embodiment, as shown in fig. 8, the corresponding processing procedure includes:
firstly, respectively expanding F-ACK information bits and F-PCB information bits, and obtaining respective corresponding information sequences, namely F-ACK information sequences and F-PCB information sequences after scrambling;
adding the F-ACK information sequences of the corresponding multiple users, and adding the F-PCB information sequences of the corresponding multiple users;
then, mapping the added F-PCB information sequence and F-ACK information sequence respectively, and mapping the mapped F-PCB information sequence and F-ACK information sequence to different physical channel resource blocks;
and finally, multiplexing the mapped information sequence containing the F-PCB information and the F-ACK information in the same physical frame, modulating by OFDM, and transmitting by an antenna.
EXAMPLE six
In this embodiment, the scrambling code may be generated by a portion of the bits of the MACID, and in this case, the spread Walsh codes for the same channel (F-ACK channel or F-PCB channel) may be different, for example, the number of MACID bits is 9 bits, and the number of Walsh codes available after spreading is 128, i.e., 27. Thus, the lower 7-bit mapping of the MACID to different Walsh codes can be used, i.e.The different users with mac id lower by 7 bits are spread by different Walsh codes. The remaining two bits in the MACID produce different scrambling codes, i.e. the users with different 2 bits in the MACID are scrambled by different scrambling codes.
Taking the above example as an example, a specific implementation structure of this embodiment is shown in fig. 9, and a specific processing procedure includes the following procedures:
firstly, dividing each F-ACK information into four groups, respectively adopting 7-bit Walsh codes to carry out spreading processing on each F-ACK information in each group, and adding the F-ACK information sequences in each group after spreading to obtain the F-ACK information sequences corresponding to each group after adding;
then, scrambling the F-ACK information sequences corresponding to each group by using scrambling codes respectively to obtain scrambled information sequences;
and finally, adding the scrambled information sequences to obtain a path of symbol, and sending the path of symbol after mapping and other processing.
Referring to fig. 9, the process for transmitting the F-PCB information is similar thereto and thus will not be described in detail.
EXAMPLE seven
In this embodiment, the F-ACK and F-PCB may be distinguished by different Walsh codes, or by different scrambling codes, or by transmitting via I and Q paths, respectively. For example, Walsh codes indexed as odd and even numbers can be allocated to the F-ACK and F-PCB, respectively, by Walsh code differentiation.
If the scrambling codes are distinguished, the scrambling codes required to be scrambled for the F-PCB are different from the scrambling codes required to be scrambled for the F-ACK; the specific implementation structure of scrambling code differentiation is shown in fig. 10, and the corresponding processing specifically includes:
firstly, scrambling and expanding the F-ACK information and the F-PCB information by using scrambling codes corresponding to user information respectively, and adding multipath information sequences after the F-ACK information is expanded and adding multipath information sequences after the F-PCB information is expanded respectively;
then, scrambling an information sequence obtained by adding one path corresponding to the F-ACK information by adopting a first scrambling code, scrambling an information sequence obtained by adding one path corresponding to the F-PCB information by adopting a second scrambling code, and adding the two scrambled information sequences again;
and finally, mapping and other processing are carried out on the information sequence obtained after the addition, and the information sequence is sent.
Example eight
In the specific implementation process of the invention, according to the transmission efficiency requirement of F-ACK and/or F-PCBB, the transmission power control of the transmission of F-ACK/F-PCB is required, and the corresponding specific control scheme comprises the following steps:
firstly, a base station classifies F-ACK and/or F-PCB to be sent, which belong to different mobile terminals, according to channel quality; the corresponding classification method may be: sorting F-ACKs and/or F-PCBs belonging to different mobile terminals according to channel quality, and grouping the sorted information according to sequence, wherein the number of the F-ACKs and/or F-PCBs to be sent in each group can be basically the same or different;
the corresponding grouping method can also be as follows: reverse traffic channels have 3 PFs (Packet Format), a PF itself represents different channel qualities, a large PF means a good channel quality, and a small PF means a poor channel quality, and thus, classification can be performed according to different PFs of terminals to which F-ACKs and/or F-PCBs belong. I.e., the corresponding F-ACK and/or F-PCB selection is divided into different groups according to the PF.
Then, different transmission powers are adopted for each group of information to be transmitted for transmission processing, and a specific transmission processing mode can adopt any one of the above embodiments; but each group of mapped physical channel resources are different, and the physical channel resources can be specifically multiplexed by methods such as frequency division multiplexing, time division multiplexing or time-frequency hybrid multiplexing; for example, F-ACK and/or F-PCB occupy the physical channel resources of a basic node, but F-ACK/F-PCB are divided into two groups, then the physical channel resources of half of the base nodes can be allocated to one group, and the physical channel resources of the remaining half of the base nodes can be allocated to the other group;
if the sending end carries out grouping according to the PF, the receiving end also needs to demodulate corresponding F-ACK and/or F-PCB information in different groups according to the received PF information.
Taking the processing of the F-ACK information as an example, in an eighth corresponding embodiment, an implementation structure of the F-ACK information transmission is shown in fig. 11, and a specific processing procedure includes:
firstly, scrambling and expanding 4 groups of symbols after F-ACK information division are respectively carried out, wherein an F-ACK1 group comprises K1 pieces of F-ACK information, an F-ACK2 group comprises K2 pieces of F-ACK information, an F-ACK3 group comprises K3 pieces of F-ACK information, and an F-ACK4 group comprises K4 pieces of F-ACK information;
then, adding the scrambled and spread information sequences of each group respectively, and carrying out power adjustment on the added information sequences according to the power requirement to be transmitted, specifically carrying out power adjustment control by introducing a power capture signal;
and finally, multiplexing, mapping and the like are carried out on each group of information sequences after power adjustment, and corresponding F-ACK information is sent through the antenna.
In summary, the present invention mainly extends the original F-ACK channel and F-PCB channel, so that the channel can support both OFDM services and CDMA services. And transmits the information bits using mac id related orthogonal code or/and scrambling code spreading and scrambling. The receiving end (mobile terminal) can determine the scrambling code and the spreading code only by the MACID information distributed to the receiving end (mobile terminal), so that the F-ACK information or/and the F-PCB information corresponding to the receiving end can be demodulated, and the control signaling and the scheduling complexity of the CDMA service can be greatly reduced.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.