# Patent

## Title
System and method for processing control information

## Abstract

A system and method for allocating network resources are disclosed herein. In one embodiment, the system and method are configured to perform: determining a redundancy version and a new data indicator indicated by control information; determining a base graph of a low density parity check code based on which of a plurality of predefined conditions the redundancy version, and/or the new data indicator satisfy; and sending a signal comprising information bits that are encoded based on the determined base graph of the low density parity check code.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. patent application Ser. No. 16/861,990, filed on Apr. 29, 2020, which is a continuation of PCT/CN2017/111756, filed on Nov. 17, 2017, each of which is incorporated by reference herein in its entirety.


TECHNICAL FIELD
The disclosure relates generally to wireless communications and, more particularly, to systems and methods for processing a signal containing control information.
BACKGROUND
In a communication system, a transmitter may encode a packet of data, also known as information bits, to obtain encoded bits, interleave the encoded bits, and map the interleaved bits to modulation symbols. The transmitter may then process and transmit the modulation symbols via a communication channel. The communication channel may distort the data transmission with a particular channel response and further degrade the data transmission with noise and interference. A receiver may obtain received symbols, which may be distorted and degraded versions of the transmitted modulation symbols. The receiver may process the received symbols to recover the transmitted information bits.
The encoding by the transmitter may allow the receiver to reliably recover the transmitted information bits with the degraded received symbols. The transmitter may perform encoding based on a Forward Error Correction (FEC) code that generates redundancy in the code bits, which is typically associated with a Hybrid Automatic Repeat Request (HARQ) technique. The receiver may utilize the redundancy to improve the likelihood of recovering the transmitted information bits.
Various types of FEC codes may be used for encoding. Some common types of FEC codes include convolutional code, Turbo code, and Low Density Parity Check (LDPC) code. A convolutional code or a Turbo code can encode a packet of k information bits and generate a coded packet of approximately r times k code bits, where 1/r is the code rate of the convolutional or Turbo code. A convolutional code can readily encode a packet of any size by passing each information bit through an encoder that can operate on one information bit at a time. A Turbo code can also support different packet sizes by employing two constituent encoders that can operate on one information bit at a time and a code interleaver that can support different packet sizes. An LDPC code may have better performance than convolutional and Turbo codes under certain operating conditions. An example of the LDPC code, typically known as a quasi-cyclic LDPC (QC-LDPC) code, that presents a constructive characteristic thereby allowing low-complexity encoding has gained particular attention.
In a New Radio (NR) communication system, when the transmitter and receiver respectively use the QC-LDPC code for encoding and decoding information bits, two predefined base graphs (BG's), typically known as BG1 (Base Graph 1) and BG2 (Base Graph 2), would be used, wherein the BG1 and BG2 correspond to respective base matrixes. For example, the transmitter selects one of BG1 and BG2 to be used based on various conditions (e.g., a code rate, a modulation order, etc.), lifts the selected BG to retrieve a parity check matrix, and uses the retrieved parity check matrix to encode the information bits to obtain an LDPC codeword. The receiver, on the other end, generally follows the similar operations (e.g., using one of BG1 and BG2) to decode and obtain the information bits.
In some cases, however, the transmitter and receiver may not use a same BG to encode and decode the information bits, respectively. For example, due to distortion or delay of the communication channel, when the receiver misses first transmitted information bits, the receiver may mistakenly treat retransmitted information bits as the first transmitted information bits. As such, the receiver may determine a wrong BG to decode the information bits, which may wrongly decode the information bits. Thus, existing systems and methods to encode and decode information bits using the QC-LDPC code are not entirely satisfactory.
SUMMARY OF THE INVENTION
The exemplary embodiments disclosed herein are directed to solving the issues relating to one or more of the problems presented in the prior art, as well as providing additional features that will become readily apparent by reference to the following detailed description when taken in conjunction with the accompany drawings. In accordance with various embodiments, exemplary systems, methods, devices and computer program products are disclosed herein. It is understood, however, that these embodiments are presented by way of example and not limitation, and it will be apparent to those of ordinary skill in the art who read the present disclosure that various modifications to the disclosed embodiments can be made while remaining within the scope of the invention.
In one embodiment, a method includes: determining a redundancy version and a new data indicator indicated by control information; determining a base graph of a low density parity check code based on which of a plurality of predefined conditions the redundancy version, and/or the new data indicator satisfy; and sending a signal comprising information bits that are encoded based on the determined base graph of the low density parity check code.
In yet another embodiment, a method includes: receiving control information indicative of a redundancy version and a current logic state of a new data indicator; determining a base graph of a low density parity check code based on which of a plurality of predefined conditions the redundancy version, and/or the new data indicator satisfy; and retrieving information bits from a received signal using the determined base graph of the low density parity check code.



BRIEF DESCRIPTION OF THE DRAWINGS
Various exemplary embodiments of the invention are described in detail below with reference to the following Figures. The drawings are provided for purposes of illustration only and merely depict exemplary embodiments of the invention to facilitate the reader's understanding of the invention. Therefore, the drawings should not be considered limiting of the breadth, scope, or applicability of the invention. It should be noted that for clarity and ease of illustration these drawings are not necessarily drawn to scale.
FIG. 1 illustrates an exemplary cellular communication network in which techniques disclosed herein may be implemented, in accordance with an embodiment of the present disclosure.
FIG. 2 illustrates block diagrams an exemplary base station and a user equipment device, in accordance with some embodiments of the present disclosure.
FIG. 3 illustrates a flow chart of an exemplary method to transmit information bits encoded by a QC-LDPC code, in accordance with some embodiments of the present disclosure.
FIG. 4 illustrates an exemplary diagram showing how a base graph 1 and a base graph each corresponds to a transport block size and a code rate, in accordance with some embodiments of the present disclosure.
FIG. 5 illustrates a flow chart of an exemplary method to retrieve information bits from a signal encoded by a QC-LDPC code, in accordance with some embodiments of the present disclosure.



DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Various exemplary embodiments of the invention are described below with reference to the accompanying figures to enable a person of ordinary skill in the art to make and use the invention. As would be apparent to those of ordinary skill in the art, after reading the present disclosure, various changes or modifications to the examples described herein can be made without departing from the scope of the invention. Thus, the present invention is not limited to the exemplary embodiments and applications described and illustrated herein. Additionally, the specific order or hierarchy of steps in the methods disclosed herein are merely exemplary approaches. Based upon design preferences, the specific order or hierarchy of steps of the disclosed methods or processes can be re-arranged while remaining within the scope of the present invention. Thus, those of ordinary skill in the art will understand that the methods and techniques disclosed herein present various steps or acts in a sample order, and the invention is not limited to the specific order or hierarchy presented unless expressly stated otherwise.
FIG. 1 illustrates an exemplary wireless communication network 100 in which techniques disclosed herein may be implemented, in accordance with an embodiment of the present disclosure. The exemplary communication network 100 includes a base station 102 (hereinafter “BS 102”) and a user equipment device 104 (hereinafter “UE 104”) that can communicate with each other via a communication link 110 (e.g., a wireless communication channel), and a cluster of notional cells 126, 130, 132, 134, 136, 138 and 140 overlaying a geographical area 101. In FIG. 1, the BS 102 and UE 104 are contained within the geographic boundary of cell 126. Each of the other cells 130, 132, 134, 136, 138 and 140 may include at least one base station operating at its allocated bandwidth to provide adequate radio coverage to its intended users. For example, the base station 102 may operate at an allocated channel transmission bandwidth to provide adequate coverage to the UE 104. The base station 102 and the UE 104 may communicate via a downlink radio frame 118, and an uplink radio frame 124 respectively. Each radio frame 118/124 may be further divided into sub-frames 120/127 which may include data symbols 122/128. In the present disclosure, the BS 102 and UE 104 are described herein as non-limiting examples of “communication nodes,” generally, which can practice the methods disclosed herein. Such communication nodes may be capable of wireless and/or wired communications, in accordance with various embodiments of the invention.
FIG. 2 illustrates a block diagram of an exemplary wireless communication system 200 for transmitting and receiving wireless communication signals, e.g., OFDM/OFDMA signals, in accordance with some embodiments of the invention. The system 200 may include components and elements configured to support known or conventional operating features that need not be described in detail herein. In one exemplary embodiment, system 200 can be used to transmit and receive data symbols in a wireless communication environment such as the wireless communication environment 100 of FIG. 1, as described above.
System 200 generally includes a base station 202 (hereinafter “BS 202”) and a user equipment device 204 (hereinafter “UE 204”). The BS 202 includes a BS (base station) transceiver module 210, a BS antenna 212, a BS processor module 214, a BS memory module 216, and a network communication module 218, each module being coupled and interconnected with one another as necessary via a data communication bus 220. The UE 204 includes a UE (user equipment) transceiver module 230, a UE antenna 232, a UE memory module 234, and a UE processor module 236, each module being coupled and interconnected with one another as necessary via a data communication bus 240. The BS 202 communicates with the UE 204 via a communication channel 250, which can be any wireless channel or other medium known in the art suitable for transmission of data as described herein.
As would be understood by persons of ordinary skill in the art, system 200 may further include any number of modules other than the modules shown in FIG. 2. Those skilled in the art will understand that the various illustrative blocks, modules, circuits, and processing logic described in connection with the embodiments disclosed herein may be implemented in hardware, computer-readable software, firmware, or any practical combination thereof. To clearly illustrate this interchangeability and compatibility of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps are described generally in terms of their functionality. Whether such functionality is implemented as hardware, firmware, or software depends upon the particular application and design constraints imposed on the overall system. Those familiar with the concepts described herein may implement such functionality in a suitable manner for each particular application, but such implementation decisions should not be interpreted as limiting the scope of the present invention.
In accordance with some embodiments, the UE transceiver 230 may be referred to herein as an “uplink” transceiver 230 that includes a RF transmitter and receiver circuitry that are each coupled to the antenna 232. A duplex switch (not shown) may alternatively couple the uplink transmitter or receiver to the uplink antenna in time duplex fashion. Similarly, in accordance with some embodiments, the BS transceiver 210 may be referred to herein as a “downlink” transceiver 210 that includes RF transmitter and receiver circuitry that are each coupled to the antenna 212. A downlink duplex switch may alternatively couple the downlink transmitter or receiver to the downlink antenna 212 in time duplex fashion. The operations of the two transceivers 210 and 230 are coordinated in time such that the uplink receiver is coupled to the uplink antenna 232 for reception of transmissions over the wireless transmission link 250 at the same time that the downlink transmitter is coupled to the downlink antenna 212. Preferably there is close time synchronization with only a minimal guard time between changes in duplex direction.
The UE transceiver 230 and the base station transceiver 210 are configured to communicate via the wireless data communication link 250, and cooperate with a suitably configured RF antenna arrangement 212/232 that can support a particular wireless communication protocol and modulation scheme. In some exemplary embodiments, the UE transceiver 608 and the base station transceiver 602 are configured to support industry standards such as the Long Term Evolution (LTE) and emerging 5G standards, and the like. It is understood, however, that the invention is not necessarily limited in application to a particular standard and associated protocols. Rather, the UE transceiver 230 and the base station transceiver 210 may be configured to support alternate, or additional, wireless data communication protocols, including future standards or variations thereof.
In accordance with various embodiments, the BS 202 may be an evolved node B (eNB), a serving eNB, a target eNB, a femto station, or a pico station, for example. In some embodiments, the UE 204 may be embodied in various types of user devices such as a mobile phone, a smart phone, a personal digital assistant (PDA), tablet, laptop computer, wearable computing device, etc. The processor modules 214 and 236 may be implemented, or realized, with a general purpose processor, a content addressable memory, a digital signal processor, an application specific integrated circuit, a field programmable gate array, any suitable programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof, designed to perform the functions described herein. In this manner, a processor may be realized as a microprocessor, a controller, a microcontroller, a state machine, or the like. A processor may also be implemented as a combination of computing devices, e.g., a combination of a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a digital signal processor core, or any other such configuration.
Furthermore, the steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in firmware, in a software module executed by processor modules 214 and 236, respectively, or in any practical combination thereof. The memory modules 216 and 234 may be realized as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. In this regard, memory modules 216 and 234 may be coupled to the processor modules 210 and 230, respectively, such that the processors modules 210 and 230 can read information from, and write information to, memory modules 216 and 234, respectively. The memory modules 216 and 234 may also be integrated into their respective processor modules 210 and 230. In some embodiments, the memory modules 216 and 234 may each include a cache memory for storing temporary variables or other intermediate information during execution of instructions to be executed by processor modules 210 and 230, respectively. Memory modules 216 and 234 may also each include non-volatile memory for storing instructions to be executed by the processor modules 210 and 230, respectively.
The network communication module 218 generally represents the hardware, software, firmware, processing logic, and/or other components of the base station 202 that enable bi-directional communication between base station transceiver 602 and other network components and communication nodes configured to communication with the base station 202. For example, network communication module 218 may be configured to support internet or WiMAX traffic. In a typical deployment, without limitation, network communication module 218 provides an 802.3 Ethernet interface such that base station transceiver 210 can communicate with a conventional Ethernet based computer network. In this manner, the network communication module 218 may include a physical interface for connection to the computer network (e.g., Mobile Switching Center (MSC)). The terms “configured for,” “configured to” and conjugations thereof, as used herein with respect to a specified operation or function, refer to a device, component, circuit, structure, machine, signal, etc., that is physically constructed, programmed, formatted and/or arranged to perform the specified operation or function.
Referring again to FIG. 1, as discussed above, when a transmitter (e.g., the BS 102) uses a BG (base graph) of a QC-LDPC code to encode information bits and transmit to a receiver (e.g., the UE 104), the UE 104 may mistakenly use a wrong (e.g., inconsistent) BG to decode the information bits, wherein such encoded information bits has been retransmitted as the UE 104 misses a first transmission. In this regard, the present disclosure provides various embodiments of systems and methods to use downlink control information (DCI), which is transmitted from a BS and received by a UE, to cause the BS and UE to use a consistent BG to encode and decode information bits, respectively. More specifically, in accordance with some embodiments, the BS and UE may respectively use various information contained in the DCI to accurately determine the correct BG by checking whether the various information satisfies either a first or second predefined condition.
FIG. 3 illustrates a flow chart of an exemplary method 300 performed by a BS to transmit information bits encoded by a QC-LDPC code, in accordance with some embodiments. The illustrated embodiment of the method 300 is merely an example. Therefore, it should be understood that any of a variety of operations may be omitted, re-sequenced, and/or added while remaining within the scope of the present disclosure.
In some embodiments, the method 300 starts with operation 302 in which downlink control information (DCI) is provided. According to some embodiments, the DCI includes various information such as, for example, a modulation and coding scheme (MCS) index (hereinafter “IMCS”), a new data indicator (hereinafter “NDI”), a redundancy version (hereinafter “RV”), a number of physical resource blocks (hereinafter “PRB”), etc. The RV as used herein is typically referred to redundancy bits when HARQ is used to retransmit information bits. Next, the method 300 proceeds to determination operation 304 in which the BS determines whether a first or second predefined condition is satisfied. In some embodiments, the first predefined condition includes at least one of the following: whether the RV is equal to RV0, whether a current logic state of the NDI is equal to a logic “0,” and whether the NDI presents a transition to a different logic state (e.g., whether the NDI has been toggled to a value different from a previously transmitted value, which indicates a first transmission); and the second predefined condition includes at least one of the following: whether the RV is equal to RV1, RV2, or RV3, whether a current logic state of the NDI is equal to a logic “1,” and whether the NDI lacks a transition to a different logic state (e.g., whether the NDI has not been toggled to a value different from a previously transmitted value, which indicates a retransmission). In some embodiments, the presence of the NDI transition is typically referred to as a “toggled NDI,” and the lack of the NDI transition is typically referred to as a “non-toggled NDI.” When the first predefined condition is satisfied, the method 300 proceeds to operation 306; and when the second predefined condition is satisfied, the method 300 proceeds to operation 308. In some embodiments, in operation 306, the BS is configured to process the various information contained in the DCI to select one from the above-mentioned BG1 and BG2 that are predefined by the QC-LDPC code; and on the other hand, in operation 308, the BS is configured to use the various information contained in the DCI to directly select one from the above-mentioned BG1 and BG2 (i.e., no further processing on the various information). After the BG is selected either at operation 306 or 308, the method 300 continues to operation 310 in which the BS uses the selected BG to encode information bits. In some embodiments, in operation 310, in addition to at least one encoding process using the selected BG being performed, one or more further steps (e.g., a rate matching step, a interleaving step, a symbol modulation step, etc.) may be performed after the information bits have been encoded. The method 300 continues to operation 312 in which the BS sends the encoded information bits. As mentioned above, since one or more further steps are performed after the information bits are encoded, in some embodiments, the BS may send the encoded information bits as one or more symbols.
In some embodiments, when the first predefined condition is satisfied (operation 306), i.e., the RV being equal to RV0, the current logic state of the NDI being equal to a logic 0, and/or the NDI transitioning to a different logic state, the BS uses the IMCS (indicated by the DCI) to determine a modulation order (Qm) and a code rate (R). More specifically, the BS may refer to a predefined table (e.g., Table 1 as shown below) to determine which modulation order and code rate that the IMCS corresponds to.









TABLE 1





MCS Index
Modulation Order
Code Rate R ×


IMCS
Qm
[1024]

















0
2
121


1
2
171


2
2
120


3
2
156.5


4
2
193


5
2
250.5


6
2
308


7
2
378.5


8
2
449


9
2
525.5


10
4
602


11
4
679


12
4
756


13
4
378


14
4
434


15
4
490


16
4
553


17
6
616


18
6
657.5


19
6
699


20
6
774.75


21
6
850.5


22
6
924.75


23
6
616.5


24
6
666


25
6
719


26
6
772


27
6
822.5


28
6
873


29
2
reserved


30
4


31
6









As shown in Table 1, there are a total of 32 different values of IMCS. In some embodiments, such 32 different values of IMCS may be grouped into a plurality of subsets: IMCSSet0 and IMCSSet1. For example, IMCSSet0 may be presented as IMCSSet0={0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28} and IMCSSet1 may be presented as IMCSSet1={29, 30, 31}. It is noted that IMCSSet0 and IMCSSet1 have no intersection, and IMCSSet0 and IMCSSet1 form a union. In some embodiments, IMCSSet1 may be grouped for retransmission data or for reserved use.
According to IMCS (indicated by the DCI), a single combination of the modulation order (Qm) and code rate (R) can be determined. Accordingly, the BS uses the PRB (also indicated by the DCI) to estimate a number of Resource Elements (NRE), and determine a layer parameter “v,” wherein such v is synonymous with “stream.” In particular, for a Multiple-Input-Multiple-Output (MIMO) BS, at least two layers (i.e., v=2) may be used, and such v is always less than or equal to a number of antennas of the MIMO BS. In some embodiments, the BS can use Qm, R, NRE, and v to determine a transport block size (TBS). More specifically, TBS=floor (TBS′/8)×8, wherein TBS'=NRE×v×Qm×R, and “floor” represents a floor function [x] that gives the largest integer less than or equal to x. After the BS estimates TBS, in some embodiments, the BS can use R and TBS to select either BG1 or BG2, which will be discussed below with respect to FIG. 4.
FIG. 4 illustrates an exemplary diagram showing how BG1 and BG2 each corresponds to the TBS and R, in accordance with various embodiments. As shown in FIG. 4, the BS may determine the BG to be used as BG1 when estimated TBS is between 292 and 3824 and estimated R is greater than 2⁄3, or when estimated TBS is greater than 3824 and estimated R is greater than 1⁄4; and the BS may determine the BG to be used as BG2 when estimated TBS is less than 292, when estimated TBS is between 292 and 3824 and estimated R is less than 2⁄3, or when estimated TBS is greater than 3824 and estimated R is less than 1⁄4.
On the other hand, in some embodiments, when the second predefined condition is satisfied (operation 308), i.e., the RV being equal to RV1, RV2, or RV3, the current logic state of the NDI being equal to a logic 1, and/or the NDI not transitioning to a different logic state, the BS uses the IMCS (indicated by the DCI) to directly select either BG1 or BG2.
In an embodiment, the BS groups the 32 different values of IMCS into a plurality of subsets: IMCSSet2, IMCSSet3, and IMCSSet4. When the IMCS (indicated by the DCI) belongs to IMCSSet2, the BS selects the BG1; and when the IMCS (indicated by the DCI) belongs to IMCSSet3, the BS selects the BG2, wherein IMCSSet4 may be grouped for retransmission data or for reserved use.
In an example, IMCSSet2 may be grouped as each IMCS in IMCSSet2 being an even integer, i.e., IMCSSet2={0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28}, IMCSSet3 may be grouped as each IMCS in IMCSSet3 being an odd integer, i.e., IMCSSet3={1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27}, and the reserved IMCSSet4={29, 30, 31}. Alternatively, IMCSSet3 may be grouped as each IMCS in IMCSSet3 being an even integer, i.e., IMCSSet3={0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28}, IMCSSet2 may be grouped as each IMCS in IMCSSet2 being an odd integer, i.e., IMCSSet2={1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27}, and the reserved IMCSSet4={29, 30, 31}. It is noted that any two of IMCSSet2, IMCSSet3, and IMCSSet4 have no intersection, and IMCSSet2, IMCSSet3, and IMCSSet4 form a union.
In another example, the grouped subsets IMCSSet2 and IMCSSet3 may satisfy the following criterion: at least b0% of IMCS in IMCSSet2 that each has a remainder after a division of the respective IMCS by an even integer “a” being less than “a/2”, and at least b1% of IMCS in IMCSSet3 that each has a remainder after a division of the respective IMCS by the even integer “a” being greater than or equal to “a/2”, and wherein b0 is a real number greater than 75 and less than 100 and b1 is a real number greater than 75 and less than 100. In yet another example, the grouped subsets IMCSSet2 and IMCSSet3 may satisfy the following criterion: at least 60% of a total number of IMCS in IMCSSet2 is greater than “N′,” and at least 60% of a total number of IMCS in IMCSSet3 is less than “N′,” and wherein N′ is equal to a sum of the total number of IMCS in IMCSSet2 and the total number of IMCS in IMCSSet3.
In another embodiment, the BS may refer to a predefined table (e.g., Table 2 as shown below) to determine which BG (either BG1 or BG2) that the IMCS corresponds to.










TABLE 2





MCS Index
Modulation Order
Code Rate R ×
Base Graph


IMCS
Qm
[1024]
Index


















0
2
121
1


1
2
171
2


2
2
120
1


3
2
156.5
2


4
2
193
1


5
2
250.5
2


6
2
308
1


7
2
378.5
2


8
2
449
1


9
2
525.5
2


10
4
602
1


11
4
679
2


12
4
756
1


13
4
378
2


14
4
434
1


15
4
490
2


16
4
553
1


17
6
616
2


18
6
657.5
1


19
6
699
2


20
6
774.75
1


21
6
850.5
2


22
6
924.75
1


23
6
616.5
2


24
6
666
1


25
6
719
2


26
6
772
1


27
6
822.5
2


28
6
873
1









29
2
reserved


30
4


31
6









As shown in Table 2, each IMCS not only corresponds to a single combination of modulation order (Qm) and a code rate (R) but also to a respective BG index (either 1 or 2). In some embodiments, BG index 1 is associated with BG1, and BG index 2 is associated with BG2. It is noted that the above-described criteria that IMCSSet2 and IMCSSet3 follow may be applied to Table 2, in accordance with some embodiments.
Referring still to operation 308 of the method 300 in FIG. 3 (i.e., the second predefined condition is satisfied), in some embodiments, the BS may use the IMCS (indicated by the DCI) and the code rate (R), corresponding to the indicated IMCS, to directly select either BG1 or BG2. More specifically, when R is greater than R1, the BS selects BS1; and when R is less than or equal to R2, the BS selects BS2, wherein R1 and R2 are each a real number less than 1, and R1 is greater than R2.
Referring still to operation 308 of the method 300 in FIG. 3 (i.e., the second predefined condition is satisfied), in some embodiments, the BS may use the IMCS and the number of physical resource blocks (PRB), both indicated by the DCI, to directly select either BG1 or BG2. More specifically, the BS selects BG1, when a remainder after division of IMCS by 2 is equal to a remainder after division of PRB by 2; and the BS selects BG2, when a remainder after division of IMCS by 2 is not equal to a remainder after division of PRB by 2. Alternatively, the BS selects BG2, when a remainder after division of IMCS by 2 is equal to a remainder after division of PRB by 2; and the BS selects BG1, when a remainder after division of IMCS by 2 is not equal to a remainder after division of PRB by 2.
Referring still to operation 308 of the method 300 in FIG. 3 (i.e., the second predefined condition is satisfied), in some embodiments, the BS may use a relationship between a first efficiency value derived from a MCS table, which will be shown below, and a second efficiency value indicated in a channel quality indicator (CQI) table, which will be shown below, to directly select either BG1 or BG2. More specifically, the first efficiency value is calculated as a product of a modulation order (Qm) and a code rate (R) that correspond to a single IMCS, which is indicated by the DCI, and the second efficiency value is listed as one of a plurality of pre-calculated efficiency values in the CQI table. Accordingly, the BS may group the 32 different values of IMCS into another plurality of subsets: IMCSSet5, IMCSSet6, IMCSSet7, and IMCSSet8, wherein each IMCS's corresponding first efficiency value in IMCSSet5 is equal to any of the plurality of pre-calculated efficiency values in the CQI table (i.e., the second efficiency value), each IMCS's corresponding first efficiency value in IMCSSet6 is equal to an average of any two adjacent ones of the plurality of pre-calculated efficiency values (i.e., the respective pre-calculated efficiency values of two adjacent CQI indexes) in the CQI table, each IMCS's corresponding first efficiency value in IMCSSet7 is not equal to any first efficiency values included in IMCSSet5 and IMCSSet6, and IMCSSet8 is reserved for retransmission or for future use.
In some embodiments, an exemplary CQI table with a maximum modulation order of 256QAM is shown in Table 3 and an exemplary MCS table for the use of sending a PDSCH (Physical Downlink Shared Channel) signal with a maximum modulation order of 8 (256QAM) is shown in Table 4. According to the above-discussed grouping principles, in some embodiments, IMCSSet5={1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27}, IMCSSet6={2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26}, IMCSSet7={0}, and IMCSSet8={28, 29, 30, 31}. Further, a maximum code rate in such an MCS table (e.g., Table 4) is equal to 0.95+Δx wherein Δx is a real number between −0.01 and +0.01. For example, as listed in Table 4, the maximum code rate indicated in the MCS table is equal to 972/1024=0.9492 wherein Δx=0.008.












TABLE 3







CQI
Modulation
code rate ×




index
order
1024
efficiency



















0
out of range












1
QPSK
78
0.1523



2
QPSK
193
0.3770



3
QPSK
449
0.8770



4
16QAM
378
1.4766



5
16QAM
490
1.9141



6
16QAM
616
2.4063



7
64QAM
466
2.7305



8
64QAM
567
3.3223



9
64QAM
666
3.9023



10
64QAM
772
4.5234



11
64QAM
873
5.1152



12
256QAM
711
5.5547



13
256QAM
797
6.2266



14
256QAM
885
6.9141



15
256QAM
972
7.5938



















TABLE 4





MCS Index
Modulation Order
code rate ×


IMCS
Qm
1024

















0
2
120


1
2
193


2
2
321


3
2
449


4
2
603


5
4
378


6
4
434


7
4
490


8
4
553


9
4
616


10
4
658


11
6
466


12
6
517


13
6
567


14
6
617


15
6
666


16
6
719


17
6
772


18
6
823


19
6
873


20
8
683


21
8
711


22
8
754


23
8
797


24
8
841


25
8
885


26
8
929


27
8
972


28
2
reserved


29
4


30
6


31
8









In some embodiments, another exemplary CQI table with a maximum modulation order of 64QAM is shown in Table 5.












TABLE 5







CQI
Modulation
code rate ×




index
order
1024
efficiency



















0
out of range












1
QPSK
78
0.1523



2
QPSK
120
0.2344



3
QPSK
193
0.3770



4
QPSK
308
0.6016



5
QPSK
449
0.8770



6
QPSK
602
1.1758



7
16QAM
378
1.4766



8
16QAM
490
1.9141



9
16QAM
616
2.4063



10
64QAM
466
2.7305



11
64QAM
567
3.3223



12
64QAM
666
3.9023



13
64QAM
772
4.5234



14
64QAM
873
5.1152



15
64QAM
948
5.5547










In some embodiments, another exemplary MCS table for the use of sending a PDSCH (Physical Downlink Shared Channel) signal with a maximum modulation order of 6 (64QAM) is shown in Table 6.









TABLE 6





MCS Index
Modulation Order
code rate ×


IMCS
Qm
1024

















0
2
120


1
2
157


2
2
193


3
2
251


4
2
308


5
2
379


6
2
449


7
2
526


8
2
602


9
2
679


10
4
340


11
4
378


12
4
434


13
4
490


14
4
553


15
4
616


16
4
658


17
6
438


18
6
466


19
6
517


20
6
567


21
6
617


22
6
666


23
6
719


24
6
772


25
6
823


26
6
873


27
6
911


28
6
948


29
2
reserved


30
4


31
6









In some embodiments, an exemplary MCS table for the use of sending a PUSCH (Physical Uplink Shared Channel) signal with a maximum modulation order of 6 (64QAM) using CP-OFDM (Cyclic Prefix Orthogonal Frequency Division Multiplexing) is shown in Table 7.









TABLE 7





MCS Index
Modulation Order
code rate ×


IMCS
Qm
1024

















0
2
100


1
2
130


2
2
161


3
2
209


4
2
257


5
2
315


6
2
374


7
2
438


8
2
502


9
2
566


10
2
630


11
4
315


12
4
362


13
4
408


14
4
461


15
4
513


16
4
548


17
4
583


18
4
646


19
4
709


20
4
771


21
6
514


22
6
555


23
6
599


24
6
643


25
6
685


26
6
727


27
6
759


28
6
790


29
2
reserved


30
4


31
6









In some embodiments, yet another MCS table for the use of sending a PUSCH (Physical Uplink Shared Channel) signal with a maximum modulation order of 8 (256QAM) using CP-OFDM (Cyclic Prefix Orthogonal Frequency Division Multiplexing) is shown in Table 8.









TABLE 8





MCS Index
Modulation Order
code rate ×


IMCS
Qm
1024

















0
2
100


1
2
161


2
2
268


3
2
374


4
2
502


5
2
630


6
4
362


7
4
408


8
4
461


9
4
513


10
4
583


11
4
646


12
4
709


13
4
771


14
6
555


15
6
599


16
6
643


17
6
685


18
6
727


19
6
790


20
6
838


21
6
886


22
8
701


23
8
738


24
8
764


25
8
821


26
8
895


27
8
949


28
2
reserved


29
4


30
6


31
8









In some embodiments, yet another exemplary MCS table for the use of sending a PUSCH (Physical Uplink Shared Channel) signal with a maximum modulation order of 6 (64QAM) using DFT-S-OFDM (Discrete Fourier Transformation Spread Orthogonal Frequency Division Multiplexing) is shown in Table 9.









TABLE 9





MCS Index
Modulation Order
code rate ×


IMCS
Qm
1024

















0
1
200


1
1
260


2
2
161


3
2
209


4
2
257


5
2
315


6
2
374


7
2
438


8
2
502


9
2
566


10
2
630


11
4
315


12
4
362


13
4
408


14
4
461


15
4
513


16
4
548


17
4
583


18
4
646


19
4
709


20
4
771


21
6
555


22
6
599


23
6
643


24
6
685


25
6
727


26
6
759


27
6
790


28
1
reserved


29
2


30
4


31
6









In some embodiments, yet another exemplary MCS table for the use of sending a PUSCH (Physical Uplink Shared Channel) signal with a maximum modulation order of 8 (256QAM) using DFT-S-OFDM (Discrete Fourier Transformation Spread Orthogonal Frequency Division Multiplexing) is shown in Table 10.









TABLE 10





MCS Index
Modulation Order
code rate ×


IMCS
Qm
1024

















0
1
200


1
2
161


2
2
268


3
2
374


4
2
502


5
2
630


6
4
362


7
4
461


8
4
513


9
4
583


10
4
646


11
4
709


12
4
771


13
6
555


14
6
599


15
6
643


16
6
685


17
6
727


18
6
790


19
6
838


20
6
886


21
8
701


22
8
738


23
8
764


24
8
821


25
8
895


26
8
949


27
1
reserved


28
2


29
4


30
6


31
8









In some embodiments, once the BS selects the BG (either BG1 or BG2), the BG can use the QC-LDPC code, as known in the art, to encode the to-be transmitted information bits. Thus, steps performed by the BS to use the BG to encode the information bits will be herein briefly described:
Step 1. Calculate an intermediate parameter kb (when BG1 is selected, kb=22; when BG2 is selected and TBS is equal to or less than 192, kb=6; when BG2 is selected and TBS is greater than 192 and less than or equal to 560, kb=8; when BG2 is selected and TBS is greater than 560 and less than or equal to 640, kb=9; and when BG2 is selected and TBS is greater than 640, kb=10).
Step 2. Calculate a lifting value Z. The lifting value Z is selected as a minimum integer greater than or equal to TBS/kb.
Step 3. Based on a plurality of predefined tables (e.g., Tables 3, 4, and 5 provided below), retrieve a parity check matrix H using the lifting value Z, which will be discussed as follows.
In general, each BG is associated with a base graph matrix, HBG. For BG1, the HBG includes 46 rows and with row indexes i=0, 1, 2, . . . , 45 and 68 columns with column indexes j=0, 1, 2, . . . , 67. For BG2, the HBG includes 42 rows with row indexes i=0, 1, 2, . . . , 41 and 52 columns with column indexes j=0, 1, 2, . . . , 51. The elements in the HBG with row and column indexes given in Table 11 (for BG1) and Table 12 (fof BG 2) are of value 1, and all other elements in HBG are of value 0. Then, The matrix H is obtained by replacing each element of HBG with a Z×Z matrix, according to the following: each element of value 0 in HBG is replaced by an all zero matrix 0 of size Z×Z; each element of value 1 in HBG is replaced by a circular permutation matrix I(Pi,j) of size Z×Z, where i and j are the row and column indexes of the element, and I(Pi,j is obtained by circularly shifting an identity matrix I of size Z×Z to the right Pi,j times. The value of Pi,j is given by Pi,j=mod(Vi,j,Z). The value of Vi,j is given by Tables 3 and 4 according to a set index iLS, which corresponds to a set of lifting values Z as shown in Table 13, and the base graph index (i.e., which BG is selected).








TABLE 11







HBG










Row
Column
Vi,j


index
index
Set index iLS
















i
j
1
2
3
4
5
6
7
8



















0
0
250
307
73
223
211
294
0
135



1
69
19
15
16
198
118
0
227



2
226
50
103
94
188
167
0
126



3
159
369
49
91
186
330
0
134



5
100
181
240
74
219
207
0
84



6
10
216
39
10
4
165
0
83



9
59
317
15
0
29
243
0
53



10
229
288
162
205
144
250
0
225



11
110
109
215
216
116
1
0
205



12
191
17
164
21
216
339
0
128



13
9
357
133
215
115
201
0
75



15
195
215
298
14
233
53
0
135



16
23
106
110
70
144
347
0
217



18
190
242
113
141
95
304
0
220



19
35
180
16
198
216
167
0
90



20
239
330
189
104
73
47
0
105



21
31
346
32
81
261
188
0
137



22
1
1
1
1
1
1
0
1



23
0
0
0
0
0
0
0
0


1
0
2
76
303
141
179
77
22
96



2
239
76
294
45
162
225
11
236



3
117
73
27
151
223
96
124
136



4
124
288
261
46
256
338
0
221



5
71
144
161
119
160
268
10
128



7
222
331
133
157
76
112
0
92



8
104
331
4
133
202
302
0
172



9
173
178
80
87
117
50 
2
56



11
220
295
129
206
109
167
16
11



12
102
342
300
93
15
253
60
189



14
109
217
76
79
72
334
0
95



15
132
99
266
9
152
242
6
85



16
142
354
72
118
158
257
30
153



17
155
114
83
194
147
133
0
87



19
255
331
260
31
156
9
168
163



21
28
112
301
187
119
302
31
216



22
0
0
0
0
0
0
105
0



23
0
0
0
0
0
0
0
0



24
0
0
0
0
0
0
0
0


2
0
106 205
68
207
258
226
132
189




1
111
250
7
203
167
35
37
4



2
185
328
80
31
220
213
21
225



4
63
332
280
176
133
302
180
151



5
117
256
38
180
243
111
4
236



6
93
161
227
186
202
265
149
117



7
229
267
202
95
218
128
48
179



8
177
160
200
153
63
237
38
92



9
95
63
71
177
0
294
122
24



10
39
129
106
70
3
127
195
68



13
142
200
295
77
74
110
155
6



14
225
88
283
214
229
286
28
101



15
225
53
301
77
0
125
85
33



17
245
131
184
198
216
131
47
96



18
205
240
246
117
269
163
179
125



19
251
205
230
223
200
210
42
67



20
117
13
276
90
234
7
66
230



24
0
0
0
0
0
0
0
0



25
0
0
0
0
0
0
0
0


3
0
121
276
220
201
187
97
4
128



1
89
87
208
18
145
94
6
23



3
84
0
30
165
166
49
33
162



4
20
275
197
5
108
279
113
220



6
150
199
61
45
82
139
49
43



7
131
153
175
142
132
166
21
186



8
243
56
79
16
197
91
6
96



10
136
132
281
34
41
106
151
1



11
86
305
303
155
162
246
83
216



12
246
231
253
213
57
345
154
22



13
219
341
164
147
36
269
87
24



14
211
212
53
69
115
185
5
167



16
240
304
44
96
242
249
92
200



17
76
300
28
74
165
215
173
32



18
244
271
77
99
0
143
120
235



20
144
39
319
30
113
121
2
172



21
12
357
68
158
108
121
142
219



22
1
1
1
1
1
1
0
1



25
0
0
0
0
0
0
0
0


4
0
157
332
233
170
246
42
24
64



1
102
181
205
10
235
256
204
211



26
0
0
0
0
0
0
0
0


5
0
205
195
83
164
261
219
185
2



1
236
14
292
59
181
130
100
171



3
194
115
50
86
72
251
24
47



12
231
166
318
80
283
322
65
143



16
28
241
201
182
254
295
207
210



21
123
51
267
130
79
258
161
180



22
115
157
279
153
144
283
72
180



27
0
0
0
0
0
0
0
0


6
0
183
278
289 
158
80
294
6
199



6
22
257
21
119
144
73
27
22



10
28
1
293
113
169
330
163
23



11
67
351
13
21
90
99
50
100



13
244
92
232
63
59
172
48
92



17
11
253
302
51
177
150
24
207



18
157
18
138
136
151
284
38
52



20
211
225
235
116
108
305
91
13



28
0
0
0
0
0
0
0
0


7
0
220
9
12
17
169
3
145
77



1
44
62
88
76
189
103
88
146



4
159
316
207
104
154
224
112
209



7
31
333
50
100
184
297
153
32



8
167
290
25
150
104
215
159
166



14
104
114
76
158
164
39
76
18



29
0
0
0
0
0
0
0
0


8
0
112
307
295
33
54
348
172
181



1
4
179
133
95
0
75
2
105



3
7
165
130
4
252
22
131
141



12
211
18
231
217
41
312
141
223



16
102
39
296
204
98
224
96
177



19
164
224
110
39
46
17
99
145



21
109
368
269
58
15
59
101
199



22
241
67
245
44
230
314
35
153



24
90
170
154
201
54
244
116
38



30
0
0
0
0
0
0
0
0


9
0
103
366
189
9
162
156
6
169



1
182
232
244
37
159
88
10
12



10
109
321
36
213
93
293
145
206



11
21
133
286
105
134
111
53
221



13
142
57
151
89
45
92
201
17



17
14
303
267
185
132
152
4
212



18
61
63
135
109
76
23
164
92



20
216
82
209
218
209
337
173
205



31
0
0
0
0
0
0
0
0


10
1
98
101
14
82
178
175
126
116



2
149
339
80
165
1
253
77
151



4
167
274
211
174
28
27
156
70



7
160
111
75
19
267
231
16
230



8
49
383
161
194
234
49
12
115



14
58
354
311
103
201
267
70
84



32
0
0
0
0
0
0
0
0


11
0
77
48
16
52
55
25
184
45



1
41
102
147
11
23
322
194
115



12
83
8
290
2
274
200
123
134



16
182
47
289
35
181
351
16
1



21
78
188
177
32
273
166
104
152



22
252
334
43
84
39
338
109
165



23
22
115
280
201
26
192
124
107



33
0
0
0
0
0
0
0
0


12
0
160
77
229
142
225
123
6
186



1
42
186
235
175
162
217
20
215



10
21
174
169
136
244
142
203
124



11
32
232
48
3
151
110
153
180



13
234
50
105
28
238
176
104
98



18
7
74
52
182
243
76
207
80



34
0
0
0
0
0
0
0
0


13
0
177
313
39
81
231
311
52
220



3
248
177
302
56
0
251
147
185



7
151
266
303
72
216
265
1
154



20
185
115
160
217
47
94
16
178



23
62
370
37
78
36
81
46
150



35
0
0
0
0
0
0
0
0


14
0
206
142
78
14
0
22
1
124



12
55
248
299
175
186
322
202
144



15
206
137
54
211
253
277
118
182



16
127
89
61
191
16
156
130
95



17
16
347
179
51
0
66
1
72



21
229
12
258
43
79
78
2
76



36
0
0
0
0
0
0
0
0


15
0
40
241
229
90
170
176
173
39



1
96
2
290
120
0
348
6
138



10
65
210
60
131
183
15
81
220



13
63
318
130
209
108
81
182
173



18
75
55
184
209
68
176
53
142



25
179
269
51
81
64
113
46
49



37
0
0
0
0
0
0
0
0


16
1
64
13
69
154
270
190
88
78



3
49
338
140
164
13
293
198
152



11
49
57
45
43
99
332
160
84



20
51
289
115
189
54
331
122
5



22
154
57
300
101
0
114
182
205



38
0
0
0
0
0
0
0
0


17
0
7
260
257
56
153
110
91
183



14
164
303
147
110
137
228
184
112



16
59
81
128
200
0
247
30
106



17
1
358
51
63
0
116
3
219



21
144
375
228
4
162
190
155
129



39
0
0
0
0
0
0
0
0


18
1
42
130
260
199
161
47
1
183



12
233
163
294
110
151
286
41
215



13
8
280
291
200
0
246
167
180



18
155
132
141
143
241
181
68
143



19
147
4
295
186
144
73
148
14



40
0
0
0
0
0
0
0
0


19
0
60
145
64
8
0
87
12
179



1
73
213
181
6
0
110
6
108



7
72
344
101
103
118
147
166
159



8
127
242
270
198
144
258
184
138



10
224
197
41
8
0
204
191
196



41
0
0
0
0
0
0
0
0


20
0
151
187
301
105
265
89
6
77



3
186
206
162
210
81
65
12
187



9
217
264
40
121
90
155
15
203



11
47
341
130
214
144
244
5
167



22
160
59
10
183
228
30
30
130



42
0
0
0
0
0
0
0
0


21
1
249
205
79
192
64
162
6
197



5
121
102
175
131
46
264
86
122



16
109
328
132
220
266
346
96
215



20
131
213
283
50
9
143
42
65



21
171
97
103
106
18
109
199
216



43
0
0
0
0
0
0
0
0


22
0
64
30
177
53
72
280
44
25



12
142
11
20
0
189
157
58
47



13
188
233
55
3
72
236
130
126



17
158
22
316
148
257
113
131
178



44
0
0
0
0
0
0
0
0


23
1
156
24
249
88
180
18
45
185



2
147
89
50
203
0
6
18
127



10
170
61
133
168
0
181
132
117



18
152
27
105
122
165
304
100
199



45
0
0
0
0
0
0
0
0


24
0
112
298
289
49
236
38
9
32



3
86
158
280
157
199
170
125
178



4
236
235
110
64
0
249
191
2



11
116
339
187
193
266
288
28
156



22
222
234
281
124
0
194
6
58



46
0
0
0
0
0
0
0
0


25
1
23
72
172
1
205
279
4
27



6
136
17
295
166
0
255
74
141



7
116
383
96
65
0
111
16
11



14
182
312
46
81
183
54
28
181



47
0
0
0
0
0
0
0
0


26
0
195
71
270
107
0
325
21
163



2
243
81
110
176
0
326
142
131



4
215
76
318
212
0
226
192
169



15
61
136
67
127
277
99
197
98



48
0
0
0
0
0
0
0
0


27
1
25
194
210
208
45
91
98
165



6
104
194
29
141
36
326
140
232



8
194
101
304
174
72
268
22
9



49
0
0
0
0
0
0
0
0


28
0
128
222
11
146
275
102
4
32



4
165
19
293
153
0
1
1
43



19
181
244
50
217
155
40
40
200



21
63
274
234
114
62
167
93
205



50
0
0
0
0
0
0
0
0


29
1
86
252
27
150
0
273
92
232



14
236
5
308
11
180
104
136
32



18
84
147
117
53
0
243
106
118



25
6
78
29
68
42
107
6
103



51
0
0
0
0
0
0
0
0


30
0
216
159
91
34
0
171
2
170



10
73
229
23
130
90
16
88
199



13
120
260
105
210
252
95
112
26



24
9
90
135
123
173
212
20
105



52
0
0
0
0
0
0
0
0


31
1
95
100
222
175
144
101
4
73



7
177
215
308
49
144
297
49
149



22
172
258
66
177
166
279
125
175



25
61
256
162
128
19
222
194
108



53
0
0
0
0
0
0
0
0


32
0
221
102
210
192
0
351
6
103



12
112
201
22
209
211
265
126
110



14
199
175
271
58
36
338
63
151



24
121
287
217
30
162
83
20
211



54
0
0
0
0
0
0
0
0


33
1
2
323
170
114
0
56
10
199



2
187
8
20
49
0
304
30
132



11
41
361
140
161
76
141
6
172



21
211
105
33
137
18
101
92
65



55
0
0
0
0
0
0
0
0


34
0
127
230
187
82
197
60
4
161



7
167
148
296
186
0
320
153
237



15
164
202
5
68
108
112
197
142



17
159
312
44
150
0
54
155
180



56
0
0
0
0
0
0
0
0


35
1
161
320
207
192
199
100
4
231



6
197
335
158
173
278
210
45
174



12
207
2
55
26
0
195
168
145



22
103
266
285
187
205
268
185
100



57
0
0
0
0
0
0
0
0


36
0
37
210
259
222
216
135
6
11



14
105
313
179
157
16
15
200
207



15
51
297
178
0
0
35
177
42



18
120
21
160
6
0
188
43
100



58
0
0
0
0
0
0
0
0


37
1
198
269
298
81
72
319
82
59



13
220
82
15
195
144
236
2
204



23
122
115
115
138
0
85
135
161



59
0
0
0
0
0
0
0
0


38
0
167
185
151
123
190
164
91
121



9
151
177
179
90
0
196
64
90



10
157
289
64
73
0
209
198
26



12
163
214
181
10
0
246
100
140



60
0
0
0
0
0
0
0
0


39
1
173
258
102
12
153
236
4
115



3
139
93
77
77
0
264
28
188



7
149
346
192
49
165
37
109
168



19
0
297
208
114
117
272
188
52



61
0
0
0
0
0
0
0
0


40
0
157
175
32
67
216
304
10
4



8
137
37
80
45
144
237
84
103



17
149
312
197
96
2
135
12
30



62
0
0
0
0
0
0
0
0


41
1
167
52
154
23
0
123
2
53



3
173
314
47
215
0
77
75
189



9
139
139
124
60
0
25
142
215



18
151
288
207
167
183
272
128
24



63
0
0
0
0
0
0
0
0


42
0
149
113
226
114
27
288
163
222



4
157
14
65
91
0
83
10
170



24
137
218
126
78
35
17
162
71



64
0
0
0
0
0
0
0
0


43
1
151
113
228
206
52
210
1
22



16
163
132
69
22
243
3
163
127



18
173
114
176
134
0
53
99
49



25
139
168
102
161
270
167
98
125



65
0
0
0
0
0
0
0
0


44
0
139
80
234
84
18
79
4
191



7
157
78
227
4
0
244
6
211



9
163
163
259
9
0
293
142
187



22
173
274
260
12
57
272
3
148



66
0
0
0
0
0
0
0
0


45
1
149
135
101
184
168
82
181
177



6
151
149
228
121
0
67
45
114



10
167
15
126
29
144
235
153
93



67
0
0
0
0
0
0
0
0

















TABLE 12







HBG










Row
Column
Vi,j


index
index
Set index iLS
















i
j
1
2
3
4
5
6
7
8



















0
0
9
174
0
72
3
156
143
145



1
117
97
0
110
26
143
19
131



2
204
166
0
23
53
14
176
71



3
26
66
0
181
35
3
165
21



6
189
71
0
95
115
40
196
23



9
205
172
0
8
127
123
13
112



10
0
0
0
1
0
0
0
1



11
0
0
0
0
0
0
0
0


1
0
167
27
137
53
19
17
18
142



3
166
36
124
156
94
65
27
174



4
253
48
0
115
104
63
3
183



5
125
92
0
156
66
1
102
27



6
226
31
88
115
84
55
185
96



7
156
187
0
200
98
37
17
23



8
224
185
0
29
69
171
14
9



9
252
3
55
31
50
133
180
167



11
0
0
0
0
0
0
0
0



12
0
0
0
0
0
0
0
0


2
0
81
25
20
152
95
98
126
74



1
114
114
94
131
106
168
163
31



3
44
117
99
46
92
107
47
3



4
52
110
9
191
110
82
183
53



8
240
114
108
91
111
142
132
155



10
1
1
1
0
1
1
1
0



12
0
0
0
0
0
0
0
0



13
0
0
0
0
0
0
0
0


3
1
8
136
38
185
120
53
36
239



2
58
175
15
6
121
174
48
171



4
158
113
102
36
22
174
18
95



5
104
72
146
124
4
127
111
110



6
209
123
12
124
73
17
203
159



7
54
118
57
110
49
89
3
199



8
18
28
53
156
128
17
191
43



9
128
186
46
133
79
105
160
75



10
0
0
0
1
0
0
0
1



13
0
0
0
0
0
0
0
0


4
0
179
72
0
200
42
86
43
29



1
214
74
136
16
24
67
27
140



11
71
29
157
101
51
83
117
180



14
0
0
0
0
0
0
0
0


5
0
231
10
0
185
40
79
136
121



1
41
44
131
138
140
84
49
41



5
194
121
142
170
84
35
36
169



7
159
80
141
219
137
103
132
88



11
103
48
64
193
71
60
62
207



15
0
0
0
0
0
0
0
0


6
0
155
129
0
123
109
47
7
137



5
228
92
124
55
87
154
34
72



7
45
100
99
31
107
10
198
172



9
28
49
45
222
133
155
168
124



11
158
184
148
209
139
29
12
56



16
0
0
0
0
0
0
0
0


7
1
129
80
0
103
97
48
163
86



5
147
186
45
13
135
125
78
186



7
140
16
148
105
35
24
143
87



11
3
102
96
150
108
47
107
172



13
116
143
78
181
65
55
58
154



17
0
0
0
0
0
0
0
0


8
0
142
118
0
147
70
53
101
176



1
94
70
65
43
69
31
177
169



12
230
152
87
152
88
161
22
225



18
0
0
0
0
0
0
0
0


9
1
203
28
0
2
97
104
186
167



8
205
132
97
30
40
142
27
238



10
61
185
51
184
24
99
205
48



11
247
178
85
83
49
64
81
68



19
0
0
0
0
0
0
0
0


10
0
11
59
0
174
46
111
125
38



1
185
104
17
150
41
25
60
217



6
0
22
156
8
101
174
177
208



7
117
52
20
56
96
23
51
232



20
0
0
0
0
0
0
0
0


11
0
11
32
0
99
28
91
39
178



7
236
92
7
138
30
175
29
214



9
210
174
4
110
116
24
35
168



13
56
154
2
99
64
141
8
51



21
0
0
0
0
0
0
0
0


12
1
63
39
0
46
33
122
18
124



3
111
93
113
217
122
11
155
122



11
14
11
48
109
131
4
49
72



22
0
0
0
0
0
0
0
0


13
0
83
49
0
37
76
29
32
48



1
2
125
112
113
37
91
53
57



8
38
35
103
143
62
27
95
167



13
222
166
26
140
47
127
186
219



23
0
0
0
0
0
0
0
0


14
1
115
19
0
36
143
11
91
82



6
145
118
138
95
51
145
20
232



11
3
21
57
40
130
8
52
204



13
232
163
27
116
97
166
109
162



24
0
0
0
0
0
0
0
0


15
0
51
68
0
116
139
137
174
38



10
175
63
73
200
96
103
108
217



11
213
81
99
110
128
40
102
157



25
0
0
0
0
0
0
0
0


16
1
203
87
0
75
48
78
125
170



9
142
177
79
158
9
158
31
23



11
8
135
111
134
28
17
54
175



12
242
64
143
97
8
165
176
202



26
0
0
0
0
0
0
0
0


17
1
254
158
0
48
120
134
57
196



5
124
23
24
132
43
23
201
173



11
114
9
109
206
65
62
142
195



12
64
6
18
2
42
163
35
218



27
0
0
0
0
0
0
0
0


18
0
220
186
0
68
17
173
129
128



6
194
6
18
16
106
31
203
211



7
50
46
86
156
142
22
140
210



28
0
0
0
0
0
0
0
0


19
0
87
58
0
35
79
13
110
39



1
20
42
158
138
28
135
124
84



10
185
156
154
86
41
145
52
88



29
0
0
0
0
0
0
0
0


20
1
26
76
0
6
2
128
196
117



4
105
61
148
20
103
52
35
227



11
29
153
104
141
78
173
114
6



30
0
0
0
0
0
0
0
0


21
0
76
157
0
80
91
156
10
238



8
42
175
17
43
75
166
122
13



13
210
67
33
81
81
40
23
11



31
0
0
0
0
0
0
0
0


22
1
222
20
0
49
54
18
202
195



2
63
52
4
1
132
163
126
44



32
0
0
0
0
0
0
0
0


23
0
23
106
0
156
68
110
52
5



3
235
86
75
54
115
132
170
94



5
238
95
158
134
56
150
13
111



33
0
0
0
0
0
0
0
0


24
1
46
182
0
153
30
113
113
81



2
139
153
69
88
42
108
161
19



9
8
64
87
63
101
61
88
130



34
0
0
0
0
0
0
0
0


25
0
228
45
0
211
128
72
197
66



5
156
21
65
94
63
136
194
95



35
0
0
0
0
0
0
0
0


26
2
29
67
0
90
142
36
164
146



7
143
137
100
6
28
38
172
66



12
160
55
13
221
100
53
49
190



13
122
85
7
6
133
145
161
86



36
0
0
0
0
0
0
0
0


27
0
8
103
0
27
13
42
168
64



6
151
50
32
118
10
104
193
181



37
0
0
0
0
0
0
0
0


28
1
98
70
0
216
106
64
14
7



2
101
111
126
212
77
24
186
144



5
135
168
110
193
43
149
46
16



38
0
0
0
0
0
0
0
0


29
0
18
110
0
108
133
139
50
25



4
28
17
154
61
25
161
27
57



39
0
0
0
0
0
0
0
0


30
2
71
120
0
106
87
84
70
37



5
240
154
35
44
56
173
17
139



7
9
52
51
185
104
93
50
221



9
84
56
134
176
70
29
6
17



40
0
0
0
0
0
0
0
0


31
1
106
3
0
147
80
117
115
201



13
1
170
20
182
139
148
189
46



41
0
0
0
0
0
0
0
0


32
0
242
84
0
108
32
116
110
179



5
44
8
20
21
89
73
0
14



12
166
17
122
110
71
142
163
116



42
0
0
0
0
0
0
0
0


33
2
132
165
0
71
135
105
163
46



9
10
61
185
51
184
24
99
205



7
164
179
88
12
6
137
173
2



10
235
124
13
109
2
29
179
106



43
0
0
0
0
0
0
0
0


34
0
147
173
0
29
37
11
197
184



12
85
177
19
201
25
41
191
135



13
36
12
78
69
114
162
193
141



44
0
0
0
0
0
0
0
0


35
1
57
77
0
91
60
126
157
85



5
40
184
157
165
137
152
167
225



11
63
18
6
55
93
172
181
175



45
0
0
0
0
0
0
0
0


36
0
140
25
0
1
121
73
197
178



2
38
151
63
175
129
154
167
112



7
154
170
82
83
26
129
179
106



46
0
0
0
0
0
0
0
0


37
10
219
37
0
40
97
167
181
154



13
151
31
144
12
56
38
193
114



47
0
0
0
0
0
0
0
0


38
1
31
84
0
37
1
112
157
42



5
66
151
93
97
70
7
173
41



11
38
190
19
46
1
19
191
105



48
0
0
0
0
0
0
0
0


39
0
239
93
0
106
119
109
181
167



7
172
132
24
181
32
6
157
45



12
34
57
138
154
142
105
173
189



49
0
0
0
0
0
0
0
0


40
2
0
103
0
98
6
160
193
78



10
75
107
36
35
73
156
163
67



13
120
163
143
36
102
82
179
180



50
0
0
0
0
0
0
0
0


41
1
129
147
0
120
48
132
191
53



5
229
7
2
101
47
6
197
215



11
118
60
55
81
19
8
167
230



51
0
0
0
0
0
0
0
0

















TABLE 13





Set index (iLS)
Set of lifting sizes (Z)







1
{2, 4, 8, 16, 32, 64, 128, 256}


2
{3, 6, 12, 24, 48, 96, 192, 384}


3
{5, 10, 20, 40, 80, 160, 320}


4
{7, 14, 28, 56, 112, 224}


5
{9, 18, 36, 72, 144, 288}


6
{11, 22, 44, 88, 176, 352}


7
{13, 26, 52, 104, 208}


8
{15, 30, 60, 120, 240}









After the parity check matrix H is determined, the information bits can be encoded as an QC-LDPC codeword. Next, as discussed above, the rate matching step, the interleaving step, and the symbol modulation step are respectively performed on the QC-LDPC codeword to generate one or more modulated symbols for transmission.
FIG. 5 illustrates a flow chart of an exemplary method 500 performed by a UE to retrieve information bits from a signal encoded by a QC-LDPC code, in accordance with some embodiments. The illustrated embodiment of the method 500 is merely an example. Therefore, it should be understood that any of a variety of operations may be omitted, re-sequenced, and/or added while remaining within the scope of the present disclosure. Since the method 500 performed by the UE is substantially similar to the method 300 performed by the BS except that encoding is replaced with decoding, the method 500 will be briefly discussed as follows.
In some embodiments, the method 500 starts with operation 502 in which downlink control information (DCI) is received. According to some embodiments, the DCI includes various information such as, for example, a modulation and coding scheme (MCS) index (hereinafter “IMCS”), a new data indicator (hereinafter “NDI”), a redundancy version (hereinafter “RV”), a number of physical resource blocks (hereinafter “PRB”), etc. Next, the method 500 proceeds to determination operation 504 in which the UE determines whether a first or second predefined condition is satisfied. In some embodiments, the first predefined condition includes at least one of the following: whether the RV is equal to RV0, whether a current logic state of the NDI is equal to a logic “0,” and whether the NDI presents a transition to a different logic state (e.g., whether the NDI has been toggled to a value different from a previously received value, which indicates a first transmission); and the second predefined condition includes at least one of the following: whether the RV is equal to RV1, RV2, or RV3, whether a current logic state of the NDI is equal to a logic “1,” and whether the NDI lacks a transition to a different logic state (e.g., whether the NDI has been toggled to a value different from a previously received value, which indicates a retransmission). When the first predefined condition is satisfied, the method 500 proceeds to operation 506; and when the second predefined condition is satisfied, the method 500 proceeds to operation 508. In some embodiments, in operation 506, the UE is configured to process the various information contained in the DCI to select one from the above-mentioned BG1 and BG2 that are predefined by the QC-LDPC code; and on the other hand, in operation 508, the UE is configured to use the various information contained in the DCI to directly select one from the above-mentioned BG1 and BG2 (i.e., no further processing on the various information). It is noted that the above-described techniques performed by the BS in operation 306 can also be performed by the UE in operation 506 to select a BG, and the above-described techniques performed by the BS in operation 308 can also be performed by the UE in operation 508 to select a BG while remaining within the scope of the present disclosure. After the BG is selected either at operation 506 or 508, the method 500 continues to operation 510 in which the UE uses the selected BG to retrieve information bits from a signal encoded by the QC-LDPC code. In some embodiments, in operation 510, in addition to at least one decoding process using the selected BG being performed, one or more further steps (e.g., a symbol de-modulation step, a step to estimate a corresponding parity check matrix as mentioned above, a de-interleaving step, a de-rate matching step, etc.) may be performed before the information bits are decoded.
While various embodiments of the invention have been described above, it should be understood that they have been presented by way of example only, and not by way of limitation. Likewise, the various diagrams may depict an example architectural or configuration, which are provided to enable persons of ordinary skill in the art to understand exemplary features and functions of the invention. Such persons would understand, however, that the invention is not restricted to the illustrated example architectures or configurations, but can be implemented using a variety of alternative architectures and configurations. Additionally, as would be understood by persons of ordinary skill in the art, one or more features of one embodiment can be combined with one or more features of another embodiment described herein. Thus, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments.
It is also understood that any reference to an element herein using a designation such as “first,” “second,” and so forth does not generally limit the quantity or order of those elements. Rather, these designations can be used herein as a convenient means of distinguishing between two or more elements or instances of an element. Thus, a reference to first and second elements does not mean that only two elements can be employed, or that the first element must precede the second element in some manner.
Additionally, a person having ordinary skill in the art would understand that information and signals can be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits and symbols, for example, which may be referenced in the above description can be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.
A person of ordinary skill in the art would further appreciate that any of the various illustrative logical blocks, modules, processors, means, circuits, methods and functions described in connection with the aspects disclosed herein can be implemented by electronic hardware (e.g., a digital implementation, an analog implementation, or a combination of the two), firmware, various forms of program or design code incorporating instructions (which can be referred to herein, for convenience, as “software” or a “software module), or any combination of these techniques. To clearly illustrate this interchangeability of hardware, firmware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware, firmware or software, or a combination of these techniques, depends upon the particular application and design constraints imposed on the overall system. Skilled artisans can implement the described functionality in various ways for each particular application, but such implementation decisions do not cause a departure from the scope of the present disclosure.
Furthermore, a person of ordinary skill in the art would understand that various illustrative logical blocks, modules, devices, components and circuits described herein can be implemented within or performed by an integrated circuit (IC) that can include a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, or any combination thereof. The logical blocks, modules, and circuits can further include antennas and/or transceivers to communicate with various components within the network or within the device. A general purpose processor can be a microprocessor, but in the alternative, the processor can be any conventional processor, controller, or state machine. A processor can also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other suitable configuration to perform the functions described herein.
If implemented in software, the functions can be stored as one or more instructions or code on a computer-readable medium. Thus, the steps of a method or algorithm disclosed herein can be implemented as software stored on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that can be enabled to transfer a computer program or code from one place to another. A storage media can be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer.
In this document, the term “module” as used herein, refers to software, firmware, hardware, and any combination of these elements for performing the associated functions described herein. Additionally, for purpose of discussion, the various modules are described as discrete modules; however, as would be apparent to one of ordinary skill in the art, two or more modules may be combined to form a single module that performs the associated functions according embodiments of the invention.
Additionally, memory or other storage, as well as communication components, may be employed in embodiments of the invention. It will be appreciated that, for clarity purposes, the above description has described embodiments of the invention with reference to different functional units and processors. However, it will be apparent that any suitable distribution of functionality between different functional units, processing logic elements or domains may be used without detracting from the invention. For example, functionality illustrated to be performed by separate processing logic elements, or controllers, may be performed by the same processing logic element, or controller. Hence, references to specific functional units are only references to a suitable means for providing the described functionality, rather than indicative of a strict logical or physical structure or organization.
Various modifications to the implementations described in this disclosure will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other implementations without departing from the scope of this disclosure. Thus, the disclosure is not intended to be limited to the implementations shown herein, but is to be accorded the widest scope consistent with the novel features and principles disclosed herein, as recited in the claims below.

## Claims

1. A method for encoding data, the method comprising:
receiving control information by a transceiver;
determining by at least one processor a redundancy version indicated by the control information;
determining by the at least one processor a base graph of a low density parity check code based on which of a plurality of predefined conditions the redundancy version satisfy, wherein a first one of the plurality of predefined conditions comprises: the redundancy version being equal to a redundancy version 0, and wherein a second one of the plurality of predefined conditions comprises: the new data indicator being not toggled, which indicates a retransmission of the encoded data, and the redundancy version being equal to one of a redundancy version 1, a redundancy version 2, or a redundancy version 3;
encoding by the at least one processor a signal comprising information bits based on the determined base graph of the low density parity check code; and
transmitting by the transceiver the encoded signal to a predetermined communication device.

2. The method of claim 1, wherein according to the first one of the plurality of predefined conditions being satisfied, the method further comprises:
determining a modulation order and a code rate based on a modulation and coding scheme index that is indicated by the control information;
determining a transport block size based on at least the modulation order and the code rate;
based on the code rate and the transport block size, determining the base graph as either a first or a second predefined base graph of the low density parity check code.

3. The method of claim 1, wherein according to the second one of the plurality of predefined conditions being satisfied, the method further comprises determining the base graph as either a first or a second predefined base graph of the low density parity check code directly according to a modulation and coding scheme index that is indicated by the control information.

4. The method of claim 1, wherein according to the second one of the plurality of predefined conditions being satisfied, the method further comprises:
determining the base graph as either a first or a second predefined base graph of the low density parity check code based on a code rate corresponding to the modulation and coding scheme index, wherein
according to the code rate being greater than a first threshold, the base graph is determined to be the first predefined base graph; and
according to the code rate being less than or equal to a second threshold, the base graph is determined to be the second predefined base graph, and
wherein the first and second thresholds are each a real number less than 1 and the first threshold is greater than the second threshold.

5. The method of claim 1, wherein according to the second one of the plurality of predefined conditions being satisfied, the method further comprises determining the base graph as either a first or a second predefined base graph of the low density parity check code directly based on a modulation and coding scheme index and a number of physical resource blocks that are both indicated by the control information.

6. A method for decoding data, the method comprising:
transmitting control information by a transceiver, wherein the control information causes a predetermined communication node to:
determine a redundancy version indicated by the control information;
determine a base graph of a low density parity check code based on which of a plurality of predefined conditions the redundancy version satisfy, wherein a first one of the plurality of predefined conditions comprises: the redundancy version being equal to a redundancy version 0, and wherein a second one of the plurality of predefined conditions comprises: the new data indicator being not toggled, which indicates a retransmission of the encoded data, and the redundancy version being equal to one of a redundancy version 1, a redundancy version 2, or a redundancy version 3;
encode a signal comprising information bits based on the determined base graph of the low density parity check code; and

receiving by the transceiver the encoded signal from the predetermined communication device.

7. The method of claim 6, wherein according to the first one of the plurality of predefined conditions being satisfied, the control information further causes the predetermined communication node to:
determine a modulation order and a code rate based on a modulation and coding scheme index that is indicated by the control information;
determine a transport block size based on at least the modulation order and the code rate; and
based on the code rate and the transport block size, determine the base graph as either a first or a second predefined base graph of the low density parity check code.

8. The method of claim 6, wherein according to the second one of the plurality of predefined conditions being satisfied, the control information further causes the predetermined communication node to determine the base graph as either a first or a second predefined base graph of the low density parity check code directly according to a modulation and coding scheme index that is indicated by the control information.

9. The method of claim 6, wherein according to the second one of the plurality of predefined conditions being satisfied, the control information further causes the predetermined communication node to:
determine the base graph as either a first or a second predefined base graph of the low density parity check code based on a code rate corresponding to the modulation and coding scheme index, wherein
according to the code rate being greater than a first threshold, the base graph is determined to be the first predefined base graph; and
according to the code rate being less than or equal to a second threshold, the base graph is determined to be the second predefined base graph, and
wherein the first and second thresholds are each a real number less than 1 and the first threshold is greater than the second threshold.

10. The method of claim 6, wherein according to the second one of the plurality of predefined conditions being satisfied, the control information further causes the predetermined communication node to determine the base graph as either a first or a second predefined base graph of the low density parity check code directly based on a modulation and coding scheme index and a number of physical resource blocks that are both indicated by the control information.

11. A wireless communication node, comprising:
a transceiver configured to receive control information; and
at least one processor configured to:
determine a redundancy version indicated by the control information,
determine a base graph of a low density parity check code based on which of a plurality of predefined conditions the redundancy version satisfy, wherein a first one of the plurality of predefined conditions comprises: the redundancy version being equal to a redundancy version 0, and wherein a second one of the plurality of predefined conditions comprises: the new data indicator being not toggled, which indicates a retransmission of the encoded data, and the redundancy version being equal to one of a redundancy version 1, a redundancy version 2, or a redundancy version 3, and
encoding by the at least one processor a signal comprising information bits based on the determined base graph of the low density parity check code, and

wherein the transceiver is further configured to transmit the encoded signal to a predetermined communication device.

12. The wireless communication node of claim 11, wherein according to the first one of the plurality of predefined conditions being satisfied, the at least one processor is further configure to:
determine a modulation order and a code rate based on a modulation and coding scheme index that is indicated by the control information;
determine a transport block size based on at least the modulation order and the code rate; and
based on the code rate and the transport block size, determine the base graph as either a first or a second predefined base graph of the low density parity check code.

13. The wireless communication node of claim 11, wherein according to the second one of the plurality of predefined conditions being satisfied, the at least one processor is further configure to determine the base graph as either a first or a second predefined base graph of the low density parity check code directly according to a modulation and coding scheme index that is indicated by the control information.

14. The wireless communication node of claim 13, wherein the at least one processor is further configured to:
according to the second one of the plurality of predefined conditions being satisfied, determine the base graph as either a first or a second predefined base graph of the low density parity check code based on a code rate corresponding to the modulation and coding scheme index, wherein
according to the code rate being greater than a first threshold, the base graph is determined to be the first predefined base graph; and
according to the code rate being less than or equal to a second threshold, the base graph is determined to be the second predefined base graph,
wherein the first and second thresholds are each a real number less than 1, and the first threshold is greater than the second threshold.

15. The wireless communication node of claim 11, wherein according to the second one of the plurality of predefined conditions being satisfied, the at least one processor is further configured to determine the base graph as either a first or a second predefined base graph of the low density parity check code directly based on a modulation and coding scheme index and a number of physical resource blocks that are both indicated by the control information.

16. A wireless communication node, comprising:
a transceiver configured to transmit control information by, wherein the control information causes a predetermined communication node to:
determine a redundancy version indicated by the control information;
determine a base graph of a low density parity check code based on which of a plurality of predefined conditions the redundancy version satisfy, wherein a first one of the plurality of predefined conditions comprises: the redundancy version being equal to a redundancy version 0, and wherein a second one of the plurality of predefined conditions comprises: the new data indicator being not toggled, which indicates a retransmission of the encoded data, and the redundancy version being equal to one of a redundancy version 1, a redundancy version 2, or a redundancy version 3; and
encode a signal comprising information bits based on the determined base graph of the low density parity check code;

wherein the transceiver is further configured to receive the encoded signal from the predetermined communication device.

17. The wireless communication node of claim 16, wherein according to the first one of the plurality of predefined conditions being satisfied, the control information further causes the predetermined communication node to:
determine a modulation order and a code rate based on a modulation and coding scheme index that is indicated by the control information;
determine a transport block size based on at least the modulation order and the code rate; and
based on the code rate and the transport block size, determine the base graph as either a first or a second predefined base graph of the low density parity check code.

18. The wireless communication node of claim 16, wherein according to the second one of the plurality of predefined conditions being satisfied, the control information further causes the predetermined communication node to determine the base graph as either a first or a second predefined base graph of the low density parity check code directly according to a modulation and coding scheme index that is indicated by the control information.

19. The wireless communication node of claim 16, wherein according to the second one of the plurality of predefined conditions being satisfied, the control information further causes the predetermined communication node to:
determine the base graph as either a first or a second predefined base graph of the low density parity check code based on a code rate corresponding to the modulation and coding scheme index, wherein
according to the code rate being greater than a first threshold, the base graph is determined to be the first predefined base graph; and
according to the code rate being less than or equal to a second threshold, the base graph is determined to be the second predefined base graph, and
wherein the first and second thresholds are each a real number less than 1 and the first threshold is greater than the second threshold.

20. The wireless communication node of claim 16, wherein according to the second one of the plurality of predefined conditions being satisfied, the control information further causes the predetermined communication node to determine the base graph as either a first or a second predefined base graph of the low density parity check code directly based on a modulation and coding scheme index and a number of physical resource blocks that are both indicated by the control information.