FIELD

The present disclosure relates to information coding.

BACKGROUND

The following description of background art may include insights, discoveries, understandings or disclosures, or associations together with disclosures not known to the relevant art prior to the present invention but provided by the invention. Some such contributions of the invention may be specifically pointed out below, whereas other such contributions of the invention will be apparent from their context.

5G New Radio (NR) is a communications technology providing new services compared to 4G causing increased requirements for spectral efficiency, for instance. Channel coding and modulation play significant roles in the physical layer as key factors in enabling fast and reliable communication.

Channel coding, also known as forward error control coding (FECC), is a process of detecting and correcting bit errors in digital communication systems. Channel coding is carried out both at the transmission and reception sides. At the transmission side, channel coding is referred to as an encoder, where extra bits (parity bits) are added with the raw data before modulation. At the reception side, channel coding is referred to as the decoder. Channel coding enables the receiver to detect and correct errors, if they occur during transmission due to noise, interference and fading.

The modulation order of a digital communication scheme is determined by the number of the different symbols (or bits) that can be transmitted using it. Modulations which have an order of 4 and above usually are called as higher-order modulations. Some examples are quadrature phase shift keying (QPSK) and m-ary quadrature amplitude modulation (m-QAM). Higher order modulation provides an option to provide higher data rates.

BRIEF DESCRIPTION

According to some aspects, there is provided the subject-matter of the independent claims. Some embodiments are defined in the dependent claims.

According to a first aspect of the present disclosure, there is provided an apparatus comprising at least one processor and at least one memory including a computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to puncture a part of block-coded bits determined by using a code generator matrix for generating a coded block a size of which as stored matches a size of a parity check matrix, puncture bits of the coded block to make a number of bits of the coded block to match a number of output bits of a distribution matcher, wherein the distribution matcher is used to create a shaped constellation according to probabilistic amplitude shaping, and generate parity bits for the punctured coded block, comprising first parity bits to be used as signs to create a symmetric part of the shaped constellation and second parity bits, wherein the second parity bits are mapped to at least one quadrature amplitude modulation symbol without shaping.

According to a second aspect of the present disclosure, there is provided a method comprising puncturing a part of block-coded bits determined by using a code generator matrix for generating a coded block a size of which as stored matches a size of a parity check matrix, puncturing bits of the coded block to make a number of bits of the coded block to match a number of output bits of a distribution matcher, wherein the distribution matcher is used to create a shaped constellation according to probabilistic amplitude shaping, and generating parity bits for the punctured coded block, comprising first parity bits to be used as signs to create a symmetric part of the shaped constellation and second parity bits, wherein the second parity bits are mapped to at least one quadrature amplitude modulation symbol without shaping.

According to a third aspect of the present disclosure, there is provided a computer program comprising instructions which, when the program is executed by an apparatus, cause the apparatus to carry out the method of the second aspect. The computer program instructions may be stored on a non-transitory computer-readable medium.

According to a fourth aspect of the present disclosure, there is provided an apparatus comprising means for carrying out the method according to the second aspect.

LIST OF DRAWINGS

FIGURE 1 illustrates an example system in accordance with at least some embodiments of the present invention;

FIGURE 2 illustrates an example parity generator codeword after puncturing in accordance with at least some embodiments of the present invention;

FIGURE 3 illustrates an example apparatus capable of supporting at least some embodiments of the present invention, and

FIGURE 4 is a flow graph of a method in accordance with at least some embodiments of the present invention. DESCRIPTION OF EMBODIMENTS

Embodiments of a channel coding method is presented which enable using probabilistic constellation shaping with block codes that are not strictly systematic but quasi-systematic, as will be described in further detail herein below. A shaped constellation transmission enables transmission of the same information using less energy, since modulation in Euclidean space is rendered more spherical in nature. In a shaped constellation transmission, usually, some signal combinations are sent more often than others, that is, the symbols do not have the same likelihood of occurring in a transmitted sequence. FIGURE 1 illustrates an example system in accordance with at least some embodiments of the present invention. In the following, different exemplifying embodiments will be described using, as an example of an access architecture to which the embodiments may be applied, a radio access architecture based on long term evolution advanced (LTE Advanced, LTE-A) or new radio (NR), also known as fifth generation (5G), without restricting the embodiments to such an architecture, however. It is obvious for a person skilled in the art that the embodiments may also be applied to other kinds of communications networks having suitable means by adjusting parameters and procedures appropriately. Some examples of other options for suitable systems are the universal mobile telecommunications system (UMTS) radio access network (UTRAN or E-UTRAN), long term evolution (LTE, the same as E-UTRA), wireless local area network (WLAN or WiFi), worldwide interoperability for microwave access (WiMAX), Bluetooth®, personal communications services (PCS), ZigBee®, wideband code division multiple access (WCDMA), systems using ultra-wideband (UWB) technology, sensor networks, mobile ad- hoc networks (MANETs) and Internet Protocol multimedia subsystems (IMS) or any combination thereof.

FIGURE 1 depicts examples of simplified system architectures only showing some elements and functional entities, all being logical units, whose implementation may differ from what is shown. The connections shown in FIGURE 1 are logical connections; the actual physical connections may be different. It is apparent to a person skilled in the art that the system typically comprises also other functions and structures than those shown in FIGURE 1. The embodiments are not, however, restricted to the system given as an example but a person skilled in the art may apply the solution to other communication systems provided with necessary properties. Examples of such other communication systems include microwave links and optical fibres, for example.

The example of FIGURE 1 shows a part of an exemplifying radio access network. FIGURE 1 shows user devices 100 and 102 configured to be in a wireless connection on one or more communication channels in a cell with an access node (such as (e/g)NodeB) 104 providing the cell. The physical link from a user device to a (e/g)NodeB is called uplink or reverse link and the physical link from the (e/g)NodeB to the user device is called downlink or forward link. It should be appreciated that (e/g)NodeBs or their functionalities may be implemented by using any node, host, server or access point etc. entity suitable for such a usage. A communications system typically comprises more than one (e/g)NodeB in which case the (e/g)NodeBs may also be configured to communicate with one another over links, wired or wireless, designed for the purpose. These links may be used for signalling purposes. The (e/g)NodeB is a computing device configured to control the radio resources of the communication system it is coupled to. The NodeB may also be referred to as a base station, access node, access point or any other type of interfacing device including a relay station capable of operating in a wireless environment. The (e/g)NodeB includes or is coupled to transceivers. From the transceivers of the (e/g)NodeB, a connection is provided to an antenna unit that establishes bi-directional radio links to user devices. The antenna unit may comprise a plurality of antennas or antenna elements. The (e/g)NodeB is further connected to core network 110 (CN or next generation core NGC). Depending on the system, the counterpart on the CN side can be a serving gateway (S-GW, routing and forwarding user data packets), packet data network gateway (P-GW), for providing connectivity of user devices (UEs) to external packet data networks, or mobile management entity (MME), etc.

The user device (also called UE, user equipment, user terminal, terminal device, etc.) illustrates one type of an apparatus to which resources on the air interface are allocated and assigned, and thus any feature described herein with a user device may be implemented with a corresponding apparatus, also including a relay node. An example of such a relay node is a layer 3 relay (self- backhauling relay) towards an access node (gNB).

The user device, or user equipment, typically refers to a portable computing device that includes wireless mobile communication devices operating with or without a subscriber identification module (SIM), including, but not limited to, the following types of devices: a mobile station (mobile phone), smartphone, personal digital assistant (PDA), handset, device using a wireless modem (alarm or measurement device, etc.), laptop and/or touch screen computer, tablet, game console, notebook, and multimedia device. It should be appreciated that a user device may also be a nearly exclusive uplink only device, of which an example is a camera or video camera loading images or video clips to a network. A user device may also be a device having capability to operate in Internet of Things (IoT) network which is a scenario in which objects are provided with the ability to transfer data over a network without requiring human-to-human or human-to-computer interaction.

Various techniques described herein may also be applied to a cyber-physical system (CPS) (a system of collaborating computational elements controlling physical entities). CPS may enable the implementation and exploitation of massive amounts of interconnected ICT devices (sensors, actuators, processors, microcontrollers, etc.) embedded in physical objects at different locations. Mobile cyber physical systems, in which the physical system in question has inherent mobility, are a subcategory of cyber-physical systems. Examples of mobile physical systems include mobile robotics and electronics transported by humans or animals.

Additionally, although the apparatuses have been depicted as single entities, different units, processors and/or memory units (not all shown in FIGURE 1) may be implemented inside these apparatuses, to enable the functioning thereof.

5G enables using multiple input - multiple output (MIMO) antennas, many more base stations or nodes than the LTE (a so-called small cell concept), including macro sites operating in co operation with smaller stations and employing a variety of radio technologies depending on service needs, use cases and/or spectrum available. 5G mobile communications supports a wide range of use cases and related applications including video streaming, augmented reality, different ways of data sharing and various forms of machine type applications (such as (massive) machine-type communications (mMTC), including vehicular safety, different sensors and real-time control. 5G is expected to have multiple radio interfaces, namely below 6GHz, cmWave and mmWave, and also being integratable with existing legacy radio access technologies, such as the LTE. Integration with the LTE may be implemented, at least in the early phase, as a system, where macro coverage is provided by the LTE and 5G radio interface access comes from small cells by aggregation to the LTE. In other words, 5G is planned to support both inter-RAT operability (such as LTE-5G) and inter-RI operability (inter-radio interface operability, such as below 6GHz - cmWave, below 6GHz - cmWave - mmWave). One of the concepts considered to be used in 5G networks is network slicing in which multiple independent and dedicated virtual sub-networks (network instances) may be created within the same infrastructure to run services that have different requirements on latency, reliability, throughput and mobility.

The current architecture in LTE networks is distributed in the radio and centralized in the core network. The low latency applications and services in 5G may require bringing the content close to the radio which leads to local break out and multi-access edge computing (MEC). 5G enables analytics and knowledge generation to occur at the source of the data. This approach requires leveraging resources that may not be continuously connected to a network such as laptops, smartphones, tablets and sensors. MEC provides a distributed computing environment for application and service hosting. It also has the ability to store and process content in close proximity to cellular subscribers for faster response time. Edge computing covers a wide range of technologies such as wireless sensor networks, mobile data acquisition, mobile signature analysis, cooperative distributed peer-to-peer ad hoc networking and processing also classifiable as local cloud/fog computing and grid/mesh computing, dew computing, mobile edge computing, cloudlet, distributed data storage and retrieval, autonomic self-healing networks, remote cloud services, augmented and virtual reality, data caching, Internet of Things (massive connectivity and/or latency critical), critical communications (autonomous vehicles, traffic safety, real-time analytics, time-critical control, healthcare applications).

The communication system is also able to communicate with other networks, such as a public switched telephone network or the Internet 112, or utilize services provided by them. The communication network may also be able to support the usage of cloud services, for example at least part of core network operations may be carried out as a cloud service (this is depicted in FIGURE 1 by“cloud” 114). The communication system may also comprise a central control entity, or a like, providing facilities for networks of different operators to cooperate for example in spectrum sharing.

Edge cloud may be brought into radio access network (RAN) by utilizing network function virtualization (NVF) and software defined networking (SDN). Using edge cloud may mean access node operations to be carried out, at least partly, in a server, host or node operationally coupled to a remote radio head or an access/network node comprising radio parts. It is also possible that node operations will be distributed among a plurality of servers, nodes or hosts. Application of cloudRAN architecture enables RAN real time functions being carried out at the RAN side (in a distributed unit, DU 104) and non-real time functions being carried out in a centralized manner (in a centralized unit, CU 108).

It should also be understood that the distribution of operations between core network operations and base station/access node operations may differ from that of the LTE or even be non existent. Some other technology advancements, such as Big Data and all-IP, may change the way networks are being constructed and managed. 5G (or new radio, NR) networks are being designed to support multiple hierarchies, where MEC servers can be placed between the core and the base station or nodeB (gNB). It should be appreciated that MEC can be applied in 4G networks as well.

5G may also utilize satellite communication to enhance or complement the coverage of 5G service, for example by providing backhauling. Possible use cases are providing service continuity for machine-to-machine (M2M) or Internet of Things (IoT) devices or for passengers on board of vehicles, or ensuring service availability for critical communications, and future railway/maritime/aeronautical communications. Satellite communication may utilise geostationary earth orbit (GEO) satellite systems, but also, or alternatively, low earth orbit (LEO) satellite systems, in particular mega-constellations (systems in which hundreds of (nano)satellites are deployed). Each satellite 106 in the constellation may cover several satellite-enabled network entities that create on-ground cells. The on-ground cells may be created through an on-ground relay node 104 or by a gNB located on-ground or in a satellite.

It is obvious for a person skilled in the art that the depicted system is only an example of a part of a radio access system and in practice, the system may comprise a plurality of (e/g)NodeBs, the user device may have an access to a plurality of radio cells and the system may comprise also other apparatuses, such as physical layer relay nodes or other network elements, etc. A cellular radio system may be implemented as a multilayer network including several kinds of cells, such as macrocells, microcells and picocells, for example. Typically, in multilayer networks, one access node provides one kind of a cell or cells, and thus a plurality of (e/g)NodeBs are required to provide such a network structure.

In information theory and coding theory with applications in computer science and telecommunication, error detection and correction enable reliable delivery of digital data over a communication channel. An error-correcting code is basically an algorithm for expressing a sequence of numbers in a manner that errors introduced can be detected and corrected. Typically, error-correction codes add redundancy to a message, and a receiver can use this redundancy to check the quality of the message as received and to recover data that has been corrupted. Error- correction codes or schemes can be either systematic or non-systematic. In a systematic scheme, a transmitter, before sending the original data bits, attaches to the message check bits (or parity bits) derived from the data bits generated by a deterministic algorithm. When a non-systematic code is used, the original message is transformed into an encoded message carrying the same information and having at least as many bits as the original message. A wireless communication channel is particularly challenging, since a wireless channel experiences not only individual bit errors caused by Gaussian noise, but also fading which causes severe dips in received power, which present challenges in terms of communicating error-intolerant information over the wireless channel.

Higher-order modulation is an enabler for achieving a high spectral efficiency. Various approaches have been considered to minimize the shaping gap of discrete constellations with uniformly distributed points. One of these approaches is probabilistic amplitude shaping (PAS). PAS is based on a reverse concatenation architecture placing the shaping operation before the forward error correction (FEC) encoding. In probabilistic shaping, as simplified, the constellation is on a uniform grid with differing probabilities per a constellation point. A "shaped constellation" transmission sends some signal combinations more often and others less frequently to optimize the signal quality at the destination or to maintain the same quality using less transmission energy. PAS, apart from achieving most of the shaping gain, it allows flexible rate adaptation with a single constellation and FEC code rate. To convert uniformly distributed input bits to non-uniformly distributed output symbols, PAS requires a distribution matcher (DM). For example, data to be transmitted is first sent to a distribution matcher and then to a FEC encoder, to produce a set of bits (or symbols) where some are shaped, and others, in particular, parity bits from the FEC encoder, are uniformly distributed. Typically, a set of DMs are stored in a memory. Each distribution matcher is usually associated with a probability mass function (PMF) to match input bits to a fixed number of output bits with values distributed according to the PMF of the distribution matcher. In general, two options for PAS exist, namely, the modulation may be directly built with a geometrical spherical shape (non-uniform constellation) or the modulation symbols may be given a spherically-shaped probability distribution (non-uniform probability distribution). The latter method appears to be easier to implement. The modulation symbols are therein made to not have the same likelihood of occurring in a transmitted sequence, with a probability distribution that mimics a discrete Gaussian distribution. PAS is an example of a shaping method based on a non-uniform probability distribution of modulation symbols. An example of the discrete Gaussian-like distribution to be achieved or approached by the modulation symbols is the Maxwell- Boltzmann, MB, distribution, which is given by probability masses that are proportional to exp(- ʋ *|s| ^{^} 2), where s is a symbol and ʋ is an MB distribution parameter. The MB distribution applies only on the symbol amplitude due to the |s| in its expression. Thus the“amplitude” in PAS, probabilistic amplitude shaping. The symbol sign is left to be free, that is, +1 and -1 have equal likelihood for a given amplitude. The PAS mechanism, that is, the distribution matcher, as such may be implemented, for instance, as laid out in citations [1] - [5], below. However, the implementation of the distribution matcher is not restricted to the solutions presented in the citations, but they should be taken only as examples.

It should be understood that PAS scheme as applied so far, is compliant only with systematic coding structures, for example systematic low density parity check, LDPC, codes. A systematic code is a code in which the input data is embedded in the encoded output. Therefore, systematic codes have the property that parity symbols may simply be appended to the information symbols. The NR-LDPC code selected by the 3rd generation partnership project, 3GPP, for 5G communication is quasi- systematic but not strictly systematic. Thus, a PAS mechanism supporting quasi-systematic block codes is of interest. The modulation constellation used for 5G are the same as those used for LTE, namely, quadrature phase shift keying, QPSK, and quadrature amplitude modulations, QAMs, 16-QAM, 64-QAM and 256-QAM. A quasi- systematic or a quasi-cyclic code may mean a code, such as LDPC code, that has quasi- systematic parity check matrices. One embodiment starts in block 400 of FIGURE 4. This embodiment is suitable for being carried out by an apparatus carrying out channel coding for transmission on a radio channel. Examples of such apparatuses are user devices and access node devices, such as a gNB. Terms “receive” and“transmit” may comprise reception or transmission via a radio path. These terms may also mean preparation of a message to the radio path for an actual transmission or processing a message received from the radio path, for example, or controlling or causing a transmission or reception, when embodiments are implemented by software. It should be appreciated that the coding of software for carrying out the embodiments shown and described below is well within the scope of a person of ordinary skill in the art.

In block 402, a part of block-coded bits or symbols determined by using a code generator matrix is punctured for generating a coded block a size of which as stored matches a size of a parity check matrix.

In LDPC coding, a generator matrix G and a sparse parity check matrix H are employed. The parity check matrices are quasi cyclic, that is, a row of this matrix follows from a cyclic right shift of the previous row in submatrices of size Zc*Zc. These submatrices are called circulants. The circulants allow a simple coding and decoding based on shift registers. 3GPP specifications allow Zc in the range 2 £ Zc £ 384. The coded bits c’ are calculated using the generator matrix G : s*G = c’. The coded bits c’ are written into a circular buffer of size N = 66* Zc for base graph, BG, 1 and N = 50*Zc for base graph 2. The size of the circular buffer does not, however, conform to the size of the H-matrices (42*52 and 46*68, respectively). For a p achieving a match, the buffer should be 68*Zc for BG 1 and 52*Zc for BG 2. This issue is solved by omitting/puncturing the first 2*Zc bits (which are significant bits, that is, bits from the most- significant end of the block) of the coded block c’ to create the final coded block c.

A result of the puncturing is that the NR-LDPC code is not strictly systematic, and consequently a normal PAS scheme cannot be used for it. In detail, running a PAS scheme on this punctured coded data block creates too few signs for the shaped amplitude values, and consequently some of the shaped amplitudes cannot be properly prepared for transmission.

In block 404, bits or symbols of the coded block are punctured to make a number of bits or symbols of the coded block match a number of output bits or symbols of a distribution matcher, wherein the distribution matcher is used to create a shaped constellation according to probabilistic amplitude shaping.

When a higher-order QAM scheme, such as 64-QAM is used, each symbol represents a grouping of bits to be transmitted. In the case of 64-QAM, each symbol has a 6-bit signature, implying that transmitted bits are grouped six at a time with each 6-bit grouping being translated to a specific symbol.

One issue due to the quasi-systematic structure of the NR-LDPC code is that the number of generated signs will not match anymore the number of symbol amplitudes at the output of the distribution matcher. Thus, some of the bits or symbols, for example the first 2*Zc bits, of the shaped symbols are also punctured.

Therefore, the number of shaped symbols after puncturing may become

wherein

V ₁ is the number of coded output symbols,

2Zc denotes additionally punctured bits, and

m _R is defined as log ₂ (sizeQAM)/2, such that the distribution matcher generates 2 ^mR-1 different amplitudes and m _R -1 bits are used to express each amplitude.

In block 406, parity bits for the punctured coded block are generated. The parity bits comprise first parity bits to be used as signs to create a symmetric part of the shaped constellation and second parity bits, wherein the second parity bits are mapped to at least one quadrature amplitude modulation symbol without shaping.

The number of second parity bits may be given by:

Wherein

n _LDPC is the length of the LDPC block code,

k _LDPC is the number of information bits going to the LDPC encoder,

2Zc denotes additionally punctured bits, and

m _R is defined as log ₂ (sizeQAM)/2, such that the distribution matcher generates 2 ^mR-1 different amplitudes and m _R -1 bits are used to express each amplitude.

The second parity bits are mapped to a M-QAM symbol. These extra symbols are sent through the channel without shaping. The number of non-shaped symbols may be defined as follows:

Wherein

#ExtraParBits is the number of non-shaped symbols,

n _LDPC is the length of the LDPC block code, k _LDPC is the number of information bits going to the LDPC encoder,

2Zc denotes additionally punctured bits, and

m _R is defined as log ₂ (sizeQAM)/2, such that the distribution matcher generates 2 ^mR-1 different amplitudes and m _R - 1 bits are used to express each amplitude.

The number of extra symbols is given by the number of bits divided by m _R . Thus, m _R -1 bits are used to create an amplitude and one bit is used as a sign, so a symbol is defined by m _R bits.

Sending the QAM symbols without shaping incurs a potential risk of performance loss compared to transmitting a completely shaped transmission sequence. However, due to the sparse structure of the parity check matrix H, such as the NR-LDPC parity check matrix, and the fact that the k _LDPC information bits are shaped to follow the desired Gaussian distribution, such as the Maxwell-Bo ltzmann, MB, distribution, it has surprisingly been found that the first- created parity bits in practice will follow the desired Gaussian, such as MB, distribution. The last created parity bits on the other hand follow merely a uniform distribution. For that reason, the first parity bits are used as extra symbols and the remaining ones as signs for the shaped amplitude symbols of the payload. The proportion of bits used as extra symbols may in practice be smaller than the one used as signs. Thus, it is ensured that the bits used to create the extra QAM symbols will in practice follow the desired Gaussian, for example MB, distribution due to the properties of the sparse parity check matrix. Therefore, all the symbols sent through the channel follow the desired distribution and transmission efficiency is not reduced.

The embodiment ends in block 408. The embodiment is naturally repeatable.

Thus, the number of total symbols sent through the channel typically equal to Vi as in the original PAS coding scheme:

Wherein

Vi is the number of coded output symbols,

n _LDPC is the length of the LDPC block code,

k _LDPC is the number of information bits going to the LDPC encoder,

2Zc denotes additionally punctured bits, and m _R is defined as log ₂ (sizeQAM)/2, such that the distribution matcher generates 2 ^mR-1 different amplitudes and m _R -1 bits are used to express each amplitude.

FIGURE 2 illustrates an example parity generator code word, or shaped symbol sequence block, after puncturing in accordance with at least some embodiments of the present invention. Shaped symbols are present in the block as the information bits. Here n _LDPC is the length of the LDPC coded block, and k _LDPc is the number of information bits going into the LDPC encoder. As can be seen, the encoded block comprises, after the puncturings, as parity bits the sign bits and also extra parity bits, which are not signs of any amplitudes/symbols. The number of the extra parity bits is given by For transmission the

extra parity bits may be mapped to at least one QAM symbol, such that the number of these non- shaped QAM symbols is given by

The number of extra symbols is given by the number of bits divided by m _R . Indeed, m _R — 1 bits are used to create an amplitude and one bit is used as a sign, so a symbol is defined by m _R bits.

FIGURE 3 illustrates an example apparatus capable of supporting at least some embodiments of the present invention. Illustrated is device 300, which may comprise, for example, a mobile communication device such as a user terminal or an access node, such as gNB or a part of it, such as CU or DU or any suitable apparatus. Comprised in device 300 is processor 310, which may comprise, for example, a single- or multi-core processor wherein a single-core processor comprises one processing core and a multi-core processor comprises more than one processing core. Processor 310 may comprise, in general, a control device. Processor 310 may comprise more than one processor. Processor 310 may be a control device. A processing core may comprise, for example, a Cortex- A8 processing core manufactured by ARM Holdings or a Steamroller processing core designed by Advanced Micro Devices Corporation. Processor 310 may comprise at least one Qualcomm Snapdragon and/or Intel Atom processor. Processor 310 may comprise at least one application- specific integrated circuit, ASIC. Processor 310 may comprise at least one field-programmable gate array, FPGA. Processor 310 may be means for performing method steps in device 300. Processor 310 may be configured, at least in part by computer instructions, to perform actions.

A processor may comprise circuitry, or be constituted as circuitry or circuitries, the circuitry or circuitries being configured to perform phases of methods in accordance with embodiments described herein. As used in this application, the term“circuitry” may refer to one or more or all of the following: (a) hardware-only circuit implementations, such as implementations in only analog and/or digital circuitry, and (b) combinations of hardware circuits and software, such as, as applicable: (i) a combination of analog and/or digital hardware circuit(s) with software/firmware and (ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and (c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation. The circuitry or circuits may also be a system-on-chip type of an integrated circuit.

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

Device 300 may comprise memory 320. Memory 320 may comprise random-access memory and/or permanent memory. Memory 320 may comprise at least one RAM chip. Memory 320 may comprise solid-state, magnetic, optical and/or holographic memory, for example. Memory 320 may be at least in part accessible to processor 310. Memory 320 may be at least in part comprised in processor 310. Memory 320 may be means for storing information. Memory 320 may comprise computer instructions that processor 310 is configured to execute. When computer instructions configured to cause processor 310 to perform certain actions are stored in memory 320, and device 300 overall is configured to run under the direction of processor 310 using computer instructions from memory 320, processor 310 and/or its at least one processing core may be considered to be configured to perform said certain actions. Memory 320 may be at least in part comprised in processor 310. Memory 320 may be at least in part external to device 300 but accessible to device 300.

An apparatus or device may also comprise means (310) for puncturing a part of block-coded bits determined by using a code generator matrix for generating a coded block a size of which as stored matches a size of a parity check matrix, means (310) for puncturing bits of the coded block to make a number of bits of the coded block to match a number of output bits of a distribution matcher, wherein the distribution matcher is used to create a shaped constellation according to probabilistic amplitude shaping, and means (310) for generating parity bits for the punctured coded block, comprising first parity bits to be used as signs to create a symmetric part of the shaped constellation and second parity bits, wherein the second parity bits are mapped to at least one quadrature amplitude modulation symbol without shaping.

Device or apparatus may be, include or be associated with at least one software application, module, unit or entity configured as arithmetic operation, or as a program (including an added or updated software routine), executed by at least one operation processor. Programs, also called program products or computer programs, including software routines, applets and macros, may be stored in any apparatus-readable data storage medium and they include program instructions to perform particular tasks. The data storage medium may be a non- transitory medium. The computer program or computer program product may also be downloaded to the apparatus. A computer program product may comprise one or more computer-executable components which, when the program is run, for example by one or more processors possibly also utilizing an internal or external memory, are configured to carry out any of the embodiments or combinations thereof described above. The one or more computer- executable components may be at least one software code or portions thereof. Computer programs may be coded by a programming language or a low-level programming language.

Embodiments provide computer programs comprising instructions which, when the program is executed by an apparatus, cause the apparatus to carry out embodiments described by means of FIGURE 4. The computer program may be in source code form, object code form, or in some intermediate form, and it may be stored in some sort of carrier, distribution medium, or computer readable medium, which may be any entity or device capable of carrying the program. Such carriers include a record medium, computer memory, read-only memory, photoelectrical and/or electrical carrier signal, telecommunications signal, and software distribution package, for example. Depending on the processing power needed, the computer program may be executed in a single electronic digital computer or it may be distributed amongst a number of computers.

Device 300 may comprise a transmitter 330. Device 300 may comprise a receiver 340. Transmitter 330 and receiver 340 may be configured to transmit and receive, respectively, information in accordance with at least one cellular or non-cellular standard. Transmitter 330 may comprise more than one transmitter. Receiver 340 may comprise more than one receiver. Transmitter 330 and/or receiver 340 may be configured to operate in accordance with global system for mobile communication, GSM, wideband code division multiple access, WCDMA, 5G, long term evolution, LTE, IS-95, wireless local area network, WLAN, Ethernet and/or worldwide interoperability for microwave access, WiMAX, standards, for example.

Device 300 may comprise a near-field communication, NFC, transceiver 350. NFC transceiver 350 may support at least one NFC technology, such as NFC, Bluetooth, Wibree or similar technologies.

Device 300 may comprise user interface, UI, 360. UI 360 may comprise at least one of a display, a keyboard, a touchscreen, a vibrator arranged to signal to a user by causing device 300 to vibrate, a speaker and a microphone. A user may be able to operate device 300 via UI 360, for example to accept incoming telephone calls, to originate telephone calls or video calls, to browse the Internet, to manage digital files stored in memory 320 or on a cloud accessible via transmitter 330 and receiver 340, or via NFC transceiver 350, and/or to play games.

Device 300 may comprise or be arranged to accept a user identity module 370. User identity module 370 may comprise, for example, a subscriber identity module, SIM, card installable in device 300. A user identity module 370 may comprise information identifying a subscription of a user of device 300. A user identity module 370 may comprise cryptographic information usable to verify the identity of a user of device 300 and/or to facilitate encryption of communicated information and billing of the user of device 300 for communication effected via device 300.

Processor 310 may be furnished with a transmitter arranged to output information from processor 310, via electrical leads internal to device 300, to other devices comprised in device 300. Such a transmitter may comprise a serial bus transmitter arranged to, for example, output information via at least one electrical lead to memory 320 for storage therein. As an alternative to a serial bus, the transmitter may comprise a parallel bus transmitter. Processor 310 may comprise a receiver arranged to receive information in processor 310, via electrical leads internal to device 300, from other devices comprised in device 300. Such a receiver may comprise a serial bus receiver arranged to, for example, receive information via at least one electrical lead from receiver 340 for processing in processor 310. As an alternative to a serial bus, the receiver may comprise a parallel bus receiver.

Device 300 may comprise further devices not illustrated in FIGURE 3. For example, where device 300 comprises a smartphone, it may comprise at least one digital camera. Some devices 300 may comprise a back-facing camera and a front-facing camera, wherein the back-facing camera may be intended for digital photography and the front-facing camera for video telephony. Device 300 may comprise a fingerprint sensor arranged to authenticate, at least in part, a user of device 300. In some embodiments, device 300 lacks at least one device described above. For example, some devices 300 may lack a NFC transceiver 350 and/or user identity module 370.

Processor 310, memory 320, transmitter 330, receiver 340, NFC transceiver 350, UI 360 and/or user identity module 370 may be interconnected by electrical leads internal to device 300 in a multitude of different ways. For example, each of the aforementioned devices may be separately connected to a master bus internal to device 300, to allow for the devices to exchange information. However, as the skilled person will appreciate, this is only one example and depending on the embodiment various ways of interconnecting at least two of the aforementioned devices may be selected without departing from the scope of the present invention.

It is to be understood that the embodiments of the invention disclosed are not limited to the particular structures, process steps, or materials disclosed herein, but are extended to equivalents thereof as would be recognized by those ordinarily skilled in the relevant arts. It should also be understood that terminology employed herein is used for the purpose of describing particular embodiments only and is not intended to be limiting.

Reference throughout this specification to one embodiment or an embodiment means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or“in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Where reference is made to a numerical value using a term such as, for example, about or substantially, the exact numerical value is also disclosed.

As used herein, a plurality of items, structural elements, compositional elements, and/or materials may be presented in a common list for convenience. However, these lists should be construed as though each member of the list is individually identified as a separate and unique member. Thus, no individual member of such list should be construed as a de facto equivalent of any other member of the same list solely based on their presentation in a common group without indications to the contrary. In addition, various embodiments and example of the present invention may be referred to herein along with alternatives for the various components thereof. It is understood that such embodiments, examples, and alternatives are not to be construed as de facto equivalents of one another but are to be considered as separate and autonomous representations of the present invention.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the preceding description, numerous specific details are provided, such as examples of lengths, widths, shapes, etc., to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.

While the forgoing examples are illustrative of the principles of the present invention in one or more particular applications, it will be apparent to those of ordinary skill in the art that numerous modifications in form, usage and details of implementation can be made without the exercise of inventive faculty, and without departing from the principles and concepts of the invention. Accordingly, it is not intended that the invention be limited, except as by the claims set forth below.

The verbs“to comprise” and“to include” are used in this document as open limitations that neither exclude nor require the existence of also un-recited features. The features recited in depending claims are mutually freely combinable unless otherwise explicitly stated. Furthermore, it is to be understood that the use of "a" or "an", that is, a singular form, throughout this document does not exclude a plurality.

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