Patent Description:
Additionally, NR is expected to introduce new encoding and decoding schemes that improve transmission and reception of data. For example, Polar codes are currently being considered as a candidate for error-correction in next-generation wireless systems such as NR. Polar codes are a relatively recent breakthrough in coding theory, which have been proven to asymptotically (for code size N approaching infinity) achieve the Shannon capacity. However, while Polar codes perform well at large values of N, for lower values of N, polar codes suffer from poor minimum distance, leading to the development of techniques such as successive cancellation list (SCL) decoding, which leverage a simple outer code having excellent minimum distance, such as a CRC or parity-check, on top of a polar inner code, such that the combined code has excellent minimum distance.

<NPL>, relates to polar code construction for PBCH" and "using same polar code construction as for the control channel. <NPL>, relates to Split-CRC Polar Code Construction for Early Termination. <NPL>, relates to Performance Comparison of CA-Polar and PC-Polar Code Candidates. <NPL>, relates to Consideration of UE ID scrambling for DCI. <NPL>, relates to a cyclic redundancy check (CRC) concatenation with polar codes based on partial protection is proposed, where only the crucial bits chosen from the total information bits are protected with the CRC.

The following summarizes some aspects of the present disclosure to provide a basic understanding of the discussed technology. Its sole purpose is to present some concepts of one or more aspects of the disclosure in summary form as a prelude to the more detailed description that is presented later.

Certain aspects of the present disclosure provide an apparatus as defined in claim <NUM>.

Certain aspects of the present disclosure provide a method as defined in claim <NUM>.

Certain aspects of the present disclosure provide a computer readable medium as defined in claim <NUM>.

The techniques may be embodied in methods, apparatuses, and computer program products.

Aspects of the present disclosure provide apparatus, methods, processing systems, and computer readable mediums for encoding/decoding, and more particularly to encoding and decoding using cyclic redundancy check (CRC) concatenated polar codes.

Also, features described with respect to some examples may be combined in some other examples, for example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein.

A CDMA network may implement a radio technology such as universal terrestrial radio access (UTRA), cdma2000, etc. UTRA includes wideband CDMA (WCDMA) and other variants of CDMA. A TDMA network may implement a radio technology such as global system for mobile communications (GSM). An OFDMA network may implement a radio technology such as NR (e.g. <NUM> RA), evolved UTRA (E-UTRA), ultra mobile broadband (UMB), IEEE <NUM> (Wi-Fi), IEEE <NUM> (WiMAX), IEEE <NUM>, Flash-OFDMA. etc. UTRA and E-UTRA are part of universal mobile telecommunication system (UMTS).

UTRA, E-UTRA, UMTS, LTE, LTE--A and GSM are described in documents from an organization named "3rd Generation Partnership Project" (3GPP). cdma2000 and UMB are described in documents from an organization named "3rd Generation Partnership Project <NUM>. For clarity, while aspects may be described herein using terminology commonly associated with <NUM> and/or <NUM> wireless technologies, aspects of the present disclosure can be applied In other generation-based communication systems, such as <NUM> and later, including NR technologies.

For example, the wireless communication network <NUM> may be a New Radio (NR) or <NUM> network. A transmitting device in the wireless communication network <NUM>, such as a UE <NUM> on the uplink or a BS <NUM> on the downlink, may be configured to cyclic redundancy check (CRC) polar encoding. If the transmitting device uses an even-weighted CRC generator polynomial, then the resulting CRC codeword is also even-weighted, leading to a cascaded polar output in which the first bit is a dummy bit, independent to the message. Accordingly, the transmitting device may avoid transmission of the dummy bit by using only odd-weighted CRC generator polynomials, dropping the first bit, or applying bit level scrambling to the CRC output before the polar encoding.

As illustrated in <FIG>, the wireless communication network <NUM> may include a number of base stations (BSs) <NUM> and other network entities. A BS may be a station that communicates with user equipments (UEs). Each BS <NUM> may provide communication coverage for a particular geographic area. In NR systems, the term "cell" and next generation Node13 (gNB or gNodeB), NR BS, <NUM> NB, access point (AP), or transmission reception point (TRP) may be interchangeable. In some examples, the base stations may be interconnected to one another and/or to one or more other base stations or network nodes (not shown) in wireless communication network <NUM> through various types of backhaul interfaces, such as a direct physical connection, a wireless connection, a virtual network, or the like using any suitable transport network.

A scheduling entity (e.g., a BS) allocates resources for communication among some or all devices and equipment within its service area or cell, the scheduling entity may be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more subordinate entities. Base stations are not the only entities that may function as a scheduling entity, in some examples, a UE may function as a scheduling entity and may schedule resources for one or more subordinate entities (e.g., one or more other UEs), and the other UEs may utilize the resources scheduled by the UE for wireless communication. In some examples, A UE may function as a scheduling entity in a peer-to-peer (P2P) network, and/or in a mesh network.

<FIG> illustrates an example logical architecture of a distributed radio access network (RAN) <NUM>, which may be implemented in the wireless communication network <NUM> illustrated in <FIG>. ANC <NUM> may be a central unit (CD) of the distributed RAN <NUM>. The backhaul interface to the next generation core network (NG-CN) <NUM> may terminate at ANC <NUM>. The backhaul interface to neighboring next generation access nodes (NG-ANs) <NUM> may terminate at ANC <NUM>. ANC <NUM> may include one or more TRPs <NUM> (e.g., cells, BSs, gNBs, etc.).

C-CU <NUM>. may be centrally deployed.

Optionally, The C-RU <NUM> may host core network functions locally.

<FIG> illustrates example components of BS <NUM> and UE <NUM> (as depicted in <FIG>), which may be used to implement aspects of the present disclosure. For example, antennas <NUM>, processors <NUM>, <NUM>, <NUM>, and/or controller/processor <NUM> of the UE <NUM> and/or antennas <NUM>, processors <NUM>, <NUM>, <NUM>, and/or controller/processor <NUM> of the BS <NUM> may be used to perform the various techniques and methods described herein for CRC concatenated polar codes.

The control information may be for the Physical Broadcast Channel (PBCH), Physical Control Format Indicator Channel (PCFICH), Physical Hybrid ARQ Indicator Channel (PHICH), Physical Downlink Control Channel (PDCCH), group common PDCCH (GC PDCCH), etc. The data may be for the Physical Downlink Shared Channel (PDSCH), etc. The processor <NUM> may process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively.

On the uplink, at UE <NUM>, a transmit processor <NUM> may receive and process data (e.g., for the Physical Uplink Shared Channel (PUSCH)) from a data source <NUM> and control information (e.g., for the Physical Uplink Control Channel (PUCCH) from the controller/processor <NUM>.

The controllers/processors <NUM> and <NUM> may direct the operation at the BS <NUM> and the UE <NUM>, respectively. The processor <NUM> and/or other processors and modules at the BS <NUM> may perform or direct the execution of processes for tire techniques described herein.

Diagram <NUM> illustrates a communications protocol stack including a RRC layer <NUM>, a PDCP layer <NUM>, a RLC layer <NUM>, a MAC layer <NUM>, and a PHY layer <NUM>.

The first option <NUM>--a may be useful in a macro cell, micro cell, or pico cell deployment.

A second option <NUM>--b shows a unified implementation of a protocol stack, in which the protocol stack is implemented in a single network access device.

The PBCH carries some basic system information, such as downlink system bandwidth, timing information within radio frame, SS burst set periodicity. system frame number, etc. The SS blocks may be organized into SS bursts to support beam sweeping.

Real-world applications of such sidelink communications may include public safety, proximity services, UE-to-network relaying, vehicle-to-vehicle (V2V) communications, Internet of Everything (IoE) communications, loT communications, mission-critical mesh, and/or various other suitable applications.

<FIG> illustrates a portion of a radio frequency (RF) modem <NUM> that may be configured to provide an encoded message for wireless transmission (e.g., using CRC concatenated polar codes described below). In one example, an encoder in a transmitting device, such as a base station (e.g., BS <NUM>) on the downlink or a UE (e.g., UE <NUM>) on the uplink, receives a message <NUM> for transmission. The message <NUM> may contain data (e.g., information bits) and/or encoded voice or other content directed to the receiving device. The encoder <NUM> encodes the message using a suitable modulation and coding scheme (MCS), typically selected based on a configuration defined by the BS <NUM> or another network entity. In some cases, the encoder <NUM> may be configured to encode the message <NUM> using techniques presented herein. The encoded bitstream <NUM> (e.g., representing to the encoded message <NUM>) may then be provided to a mapper <NUM> that generates a sequence of Tx symbols <NUM> that are modulated, amplified and otherwise processed by Tx chain <NUM> to produce an RF signal <NUM> for transmission through antenna <NUM>.

<FIG> illustrates a portion of a RF modem <NUM> that may be configured to receive and decode a wirelessly transmitted signal including an encoded message (e.g., a message encoded using techniques presented herein). In various examples, the modem <NUM> receiving the signal may reside at the receiving device, such as the UE <NUM> on the downlink or the BS <NUM> on the uplink, or at any other suitable apparatus or means for carrying out the described functions. An antenna <NUM> provides the RF signal <NUM> to the receiving device. An Rx chain <NUM> processes and demodulates the RF signal <NUM> and may provide a sequence of symbols <NUM> to a demapper <NUM>, which produces a sequence of a-priori probabilities <NUM>, often represented as log-likelihood ratios (LLRs) corresponding to the encoded message. A decoder <NUM> may then be used to decode m-bit information strings from a bitstream that has been encoded using a coding scheme (e.g., as described herein). The decoder <NUM> may comprise a CRC concatenated polar decoder.

According to certain aspects, the encoder <NUM> may be a CRC concatenated polar encoder. As shown in <FIG>, encoder <NUM> may include a CRC outer code encoder 906a and polar inner code encoder 906b. The encoder <NUM> may receive the payload of K information bits to be transmitted and the CRC outer code encoder 906a may add CRC bits and output K+r CRC encoded bits to the polar inner code encoder 906b. The polar inner code encoder 906b uses polar code and produces N polar encoded bits. Similarly, decoder <NUM> may include a polar decoder 1016a and CRC decoder 1016b as shown in <FIG>.

Polar codes have been adopted for error-correction in NR systems. Polar codes may be used to encode a stream of bits for transmission. Polar codes are a capacity-achieving coding scheme with almost linear (in block length) encoding and decoding complexity. Polar codes have many desirable properties such as deterministic construction (e.g., based on a fast Hadamard transform), very low and predictable error floors, and simple successive-cancellation (SC) based decoding.

Polar codes are linear block codes of length N=<NUM>n where their generator matrix G is constructed using the nth Kronecker power of the kernel matrix <MAT> , denoted by Gn. For example, Equation (<NUM>) shows the resulting generator matrix for n=<NUM>.

Equation (<NUM>) shows the resulting generator matrix for n=<NUM>.

The encoder <NUM> can generate a codeword by using the generator matrix to encode a number of input bits consisting of K information bits and N-K "frozen" bits which contain no information and are "frozen" to a known value, such as zero. For example, given a number of input bits u = (u<NUM>, u<NUM>,. , un-<NUM>), a resulting codeword vector x = (x<NUM> , x<NUM>,. , xn-<NUM>) may be generated by encoding the input bits using the generator matrix G. Thus, x[<NUM>:N] = u[<NUM>:K]*G. This resulting codeword may then be rate matched and transmitted by a base station over a wireless medium and received by a UE. The frozen bits may be selected as the least reliable bits (e.g., the rows with the lowest weight). In one example, referring to the matrix in Eq. (<NUM>), u = (<NUM>, <NUM>, <NUM>, u<NUM>, <NUM>, u<NUM>, u<NUM>, u<NUM>) with u<NUM>, u<NUM>, u<NUM>, and u<NUM> set as frozen bits. In this example: <MAT>.

When the received vectors are decoded, for example by using a Successive Cancellation (SC) decoder (e.g., decoder <NUM>), every estimated bit, ûi, has a predetermined error probability given that bits û<NUM>-ûi-<NUM> were correctly decoded, that, for extremely large code size N, tends towards either <NUM> or <NUM>. Moreover, the proportion of estimated bits with a low error probability tends towards the capacity of the underlying channel. Polar codes exploit this phenomenon, called channel polarization, by using the most reliable K bits to transmit information, while setting to a predetermined value (such as <NUM>), also referred to as freezing, the remaining (N-K) bits, for example as explained below.

Polar codes transform the channel into N parallel "virtual" channels for the N information and frozen bits. If C is the capacity of the channel, then, for sufficiently large values of N, there are almost N*C channels which are extremely reliable and there are almost N(<NUM> - C) channels which are extremely unreliable. The basic polar coding scheme then involves freezing (i.e., setting to a known value, such as zero) the input bits in u corresponding to the unreliable channels, while placing information bits only in the bits of u corresponding to reliable channels. For short-to-medium N, this polarization may not be complete in the sense there could be several channels which are neither completely unreliable nor completely reliable (i.e., channels that are marginally reliable). Depending on the rate of transmission, bits corresponding to these marginally reliable channels may be either frozen or used for information bits.

In one example, a Polar decoder employs the successive cancellation (SC) or successive cancellation list (SCL) decoding algorithm. An SC decoding algorithm essentially operates by performing a recursive depth-first traversal of a decoding tree, to convert the bitstream <NUM> (e.g., a sequence of LLRs) into the message <NUM> corresponding to the message <NUM> (e.g., when the decoding is successful).

As mentioned above, CRC concatenated polar coding may be performed, whereby the encoder <NUM> first performed CRC encoding on the K information bits to produce K+r (information bits + checksums) CRC encoded bits and then polar encodes the K+r CRC encoded bits to produce N polar encoded bits. The CRC outer code encoder 1006a uses generator polynomial for the CRC algorithm. In one example, an example generator polynomial x<NUM> + x<NUM> + <NUM> can be represented as a binary row vector containing the coefficients in descending orders of power, in this example, [<NUM><NUM><NUM><NUM>].

After the polar encoding, tire first code bit x[<NUM>] is equal to the modulo-<NUM> sum of all of the CRC output bits-regardless of the selected information bit locations of the polar code.

Because CRC code is a cyclic code, a given CRC generator polynomial g(X) = Xr +. + <NUM>, any n-length codeword can be expressed as u(X) = a(X)g(X), where a(X) is the message polynomial with maximum order n-r. If the CRC generator polynomial is even weighted, then g(X = <NUM>) = <NUM>. Hence, u(X = <NUM>) = a(X)*<NUM> = <NUM>. Thus, when the CRC generator polynomial is even weighted, the resulting CRC codeword is also even weighted. In this case, the first code bit x[<NUM>] (which may be the modulo-<NUM> sum of the CRC encoded bits) in the cascaded polar output (the N polar encoded bits) always equals to a dummy bit (e.g., always a fixed value, such as "<NUM>"), which is independent to the message (the K information bits input to the CRC encoder). Thus, the data rate of the encoder may be impacted.

Accordingly, techniques for CRC concatenated polar encoding are desirable that avoid transmission of the dummy bits.

As noted above, polar codes are a relatively recent breakthrough in coding theory and have been proven to achieve Shannon capacity for large values of a code block size N, whereas for smaller code block sizes, polar codes may suffer from poor minimum distance. Techniques such as successive cancellation list (SCL) decoding, leverage a simple outer code having excellent minimum distance, such as a cyclic redundancy check (CRC) or parity-check, on top of a polar inner code, such that the combined code has excellent minimum distance. Although the addition of CRC outer code improves the error-rate performance at low values of N, use of even-weighted CRC generator polynomials leads to additional dummy bits in the polar output as discussed above. Transmission of dummy bits may reduce the efficiency, thereby reducing processing speed and efficiency, and increasing power consumption.

Thus, aspects of the present disclosure propose techniques for avoiding transmission of dummy bits in CRC concatenated polar codes. For example, in some cases, only odd-weighted CRC generator polynomials may be selected. In some cases, when even-weighted CRC generator polynomials are used, the dummy bit may be discarded, and/or bit-level scrambling can be performed on the CRC bits to avoid generation of the dummy bit. Thereby, the encoding can achieve the benefits of minimum distance, while avoiding the transmission of dummy bits.

<FIG>, <FIG>, and <FIG> illustrate example operations <NUM>, <NUM>, and <NUM>, respectively, for encoding bits of information, for example, for CRC concatenated polar encoding that avoids transmission of dummy bits, in accordance with certain aspects of the present disclosure. According to certain aspects, operations <NUM>, <NUM>, and/or <NUM> may be performed by any suitable encoding device, such as a base station (e.g., a BS <NUM> in the wireless communication network <NUM>) on the downlink or a user equipment (e.g., a UE <NUM> in the wireless communication network <NUM>) on the uplink.

The encoding device may include one or more components as illustrated in <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, and/or <NUM> which may be configured to perform the operations described herein. For example, the antenna <NUM>, modulator/demodulator <NUM>, transmit processor <NUM>, controller/processor <NUM>, and/or memory <NUM> of the BS <NUM>, as illustrated in <FIG>, may perform the operations described herein. Additionally or alternatively, the antenna <NUM>, demodulator/modulator <NUM>, transmit processor <NUM>, controller/processor <NUM>, and/or memory <NUM> of the UE <NUM>, as illustrated in <FIG>, may perform the operations described herein. Additionally or alternatively, the encoder <NUM>, mapper <NUM>, TX Chain <NUM>, and/or antenna <NUM> as illustrated in <FIG> may be configured to perform the operations described herein.

Although not shown, complementary operations to the operations <NUM>, <NUM>, and <NUM> may be performed for decoding bits of information. The complementary operations may, for example, be performed by any suitable decoding device, such as a BS (e.g., BS <NUM> in the wireless communication network <NUM>) on the uplink and/or a UE (e.g., UE <NUM> in the wireless communication network <NUM>) on the downlink. The decoding device may include one or more components as illustrated in <FIG>, <FIG>, and <FIG> which may be configured to perform the operations described herein. For example, the antenna <NUM>, modulator/demodulator <NUM>, transmit processor <NUM>, controller/processor <NUM>, and/or memory <NUM> of the BS <NUM>, as illustrated in <FIG>, may perform the operations described herein. Additionally or alternatively, the antenna <NUM>, demodulator/modulator <NUM>, transmit processor <NUM>, controller/processor <NUM>, and/or memory <NUM>. of the UE <NUM>, as illustrated in <FIG>, may perform the operations described herein. Additionally or alternatively, the decoder <NUM>, demapper <NUM>, RX Chain <NUM>, and/or antenna <NUM> as illustrated in <FIG> may be configured to perform the complementary operations.

In a claimed embodiment the first bit of the codeword is discarded to avoid transmission of the dummy bit, even when an even-weighted CRC polynomial is used for the CRC encoding. <FIG> illustrates example operations <NUM> for CRC concatenated polar encoding bits of information including discarding a dummy bit, in accordance with a claimed embodiment of the present disclosure. Operations <NUM> begin, at <NUM>, by obtaining the bits of information to be transmitted.

At <NUM>, the encoder performs CRC outer encoding of the bits of information using an even-weighted generator polynomial to produce CRC encoded bits.

At <NUM>, the encoder performs polar inner encoding of the CRC encoded bits to generate a codeword. The polar encoding may include setting one or more most reliable bits as information bits and setting one or more other bits as frozen bits.

At <NUM>, the encoder discards a first code bit (e.g., the x[<NUM>] bit) at a beginning of the codeword to produce a shortened codeword. The first code bit is equal to a modulo-<NUM> sum of the CRC encoded bits. For even-weighted CRC generator polynomials, the first code bit may always be equal to a fixed bit value, such as a "<NUM>". Thus, the first code bit (e.g., the x[<NUM>] bit) may be a dummy bit. Discarding the first code bit produces the shortened codeword.

At <NUM>, the encoder transmits the shortened codeword in accordance with a radio technology (e.g., <NUM>) over a channel via one or more antenna elements situated proximate a transmitter. By discarding the dummy bit, the transmitting device avoids transmission of the dummy bit and may improve the efficiency of the transmission, while also achieving the improved minimum distance of using CRC polar encoding.

As shown in <FIG>, in some examples, the encoder <NUM> avoids transmission of dummy bits by discarding the x[<NUM>] bit of the N output polar encoded bits from the polar encoder. As mentioned above, when an even-weighted CRC generator polynomial is used, this bit is always a bit-<NUM>, independent of the K message bits input to the CRC encoder. Thus, discarding this bit may avoid transmission of the dummy bit.

In one example, the bit-level scrambling of the CRC encoded output can be done before inputting to the polar encoder to avoid generation of the dummy bit. <FIG> illustrates example operations <NUM> for CRC concatenated polar encoding bits of information including performing bit-level scrambling of CRC encoded bits, in accordance with certain aspects of the present disclosure. Operations <NUM> begin, at <NUM>, by obtaining the bits of information to be transmitted.

At <NUM>, the encoder performs bit scrambling of the CRC encoded bits. The bit scrambling may ensure that a first code bit (e.g., the x[<NUM>] code bit) at a beginning of the codeword is equal to a non-zero bit at least sometimes.

At <NUM>, the encoder performs polar inner encoding of the scrambled CRC encoded bits to generate a codeword.

At <NUM>, the encoder transmits the codeword in accordance with a radio technology (e.g., <NUM>) over a channel via one or more antenna elements situated proximate a transmitter. By scrambling the CRC encoded bits, the transmitting device avoids generation of the dummy bit and may improve the efficiency of the transmission, while also achieving the improved minimum distance of using CRC polar encoding.

As shown in <FIG>, in some examples, the encoder <NUM> may avoid transmission of dummy bits by using bit-level scrambling of the K+r CRC encoded bits output from the CRC encoder-before they are input to the polar encoder. As mentioned above, when an even-weighted CRC generator polynomial is used, the x[<NUM>] bit of the N output polar encoded bits is always a bit-<NUM>, independent of the K message bits input to the CRC encoder. However, by scrambling the K+r CRC encoded bits output by the CRC encoder, at least some of the time this bit may be non-zero and transmission of the dummy bit can be avoided. Although not shown, the scrambling may be performed by a bit scrambling module at the encoder <NUM>.

In one example, only odd-weighted CRC generator polynomials may be selected for the CRC encoding to avoid generation of the dummy bit. <FIG> illustrates example operations <NUM> for CRC concatenated polar encoding bits of information including selecting only odd-weighted CRC generator polynomials, in accordance with certain aspects of the present disclosure. Operations <NUM> begin, at <NUM>, by obtaining the bits of information to be transmitted.

At <NUM>, the encoder selects only odd-weighted generator polynomials for performing CRC outer encoding of the bits of information to produce CRC encoded bits. The selection of only odd-weighted polynomials for performing the CRC outer encoding may ensure that a first code bit [e.g., the x[<NUM>] code bit) at a beginning of the codeword is equal to a non-zero bit at least sometimes.

At <NUM>, the encoder transmits the codeword in accordance with a radio technology (e.g., <NUM>) over a channel via one or more antenna elements situated proximate a transmitter. By selecting only odd-weighted generator polynomials for the CRC encoding, the transmitting device avoids generation of the dummy bit and may improve the efficiency of the transmission, while also achieving the improved minimum distance of using CRC polar encoding.

As shown in <FIG>, in some examples, the encoder <NUM> may avoid transmission of dummy bits by selecting odd-weighted CRC generator polynomial for the CRC encoding. As mentioned above, when an even-weighted CRC generator polynomial is used, the x[<NUM>] bit of the N output polar encoded bits is always a bit-<NUM>, independent of the K message bits input to the CRC encoder. Thus, by selecting an odd-weighted CRC generator polynomial for the CRC encoder, this bit may be non-zero and transmission of the dummy bit can be avoided.

<FIG> is an example graph illustrating encoding performance of various CRC generator polynomials. Curve <NUM> corresponds to the even-weighted CRC <NUM> polynomial g(x)=[<NUM>] and curve <NUM> corresponds to the odd-weighted CRC <NUM> polynomial g(x)=[<NUM>]. As shown in the graph, performance for CRC concatenated polar codes using the even-weighted CRC generator polynomial (curve <NUM>) has worse performance than the odd-weighted (curve <NUM>). Avoiding transmission of dummy bits may improve block error rate (BLER).

<FIG> illustrates a communications device <NUM> that may include various components (e.g., corresponding to means-plus-function components) configured to perform operations for the techniques disclosed herein, such as the operations <NUM>, <NUM>, and <NUM> illustrated in <FIG>, <FIG>, and <FIG>, respectively.

The processing system <NUM> includes a processor <NUM> coupled to a computer-readable medium/memory <NUM> via a bus <NUM>. In certain aspects, the computer-readable medium/memory <NUM> is configured to store instructions (e.g., computer executable code) that when executed by the processor <NUM>, cause the processor <NUM>. to perform the operations illustrated in <FIG>, <FIG>, and <FIG>, or other operations for performing the various techniques discussed herein for avoiding transmission of dummy bits in CRC polar encoding. In certain aspects, computer-readable medium/memory <NUM> stores code <NUM> for obtaining information bits. The computer readable medium/memory <NUM> stores code <NUM> for CRC outer encoding. The code <NUM> for CRC outer encoding may include code for selecting the CRC-generator polynomial (e.g., for selecting only odd-weighted polynomials in some cases). The computer readable medium/memory <NUM> may store code <NUM> for bit scrambling (e.g., if an even-weighted polynomial is selected). The computer readable medium/memory <NUM> stores code <NUM> for polar inner encoding. The computer readable medium/memory <NUM> may store code <NUM> for discarding a first code bit (e.g., if an even-weighted polynomial is selected). The computer readable medium/memory <NUM> stores code <NUM> for transmitting the codeword.

In certain aspects, the processor <NUM> has circuitry configured to implement the code stored in the computer-readable medium/memory <NUM>. The processor <NUM> includes encoder circuitry <NUM>. The encoder circuitry <NUM> includes circuitry <NUM> for obtaining information bits; circuitry <NUM> for CRC outer encoding; and circuitry <NUM> for polar inner encoding. The circuitry <NUM> for CRC outer encoding may include circuitry for generator polynomial selection (e.g., for selecting only odd-weighted polynomials in some cases). The encoder circuitry <NUM> may include circuitry <NUM> for bit scrambling (e.g., if an even-weighted polynomial is selected). The encoder circuitry <NUM> may include circuitry <NUM> for discarding a first code bit (e.g., if an even-weighted polynomial is selected).

It should be noted that the terms distributed, inserted, interleaved may be used interchangeably and generally refer to the strategic placement of outer-code bits within an information stream inputted into an encoder, such as a Polar encoder. Additionally, it should be understood that, while aspects of the present disclosure propose techniques for reducing the search space of nodes in a polar decoding tree with relation to wireless communication system, the techniques presented herein are not limited to such wireless communication system. For example, the techniques presented herein may equally apply to any other system that uses encoding schemes, such as data storage or compression, or fiber communication systems, hard-wire "copper" communication systems, and the like.

All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims.

Examples of machine-readable storage media may include, by way of example, RAM (Random Access Memory), flash memory, ROM (Read Only Memory), PROM (Programmable Read-. Only Memory), EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), registers, magnetic disks, optical disks, hard drives, or any other suitable storage medium, or any combination thereof. The machine-readable media may be embodied in a computer--program product.

For example, instructions for performing the operations described herein and illustrated in <FIG>, <FIG>, and <FIG>.

Claim 1:
An apparatus (<NUM>) for wireless communications, comprising:
at least one processor (<NUM>) coupled with a memory (<NUM>) and comprising at least one encoder circuit (<NUM>) configured to:
obtain bits of information to be transmitted;
perform cyclic redundancy check, CRC, outer encoding of the bits of information using an even-weighted generator polynomial to produce CRC encoded bits;
perform polar inner encoding of the CRC encoded bits to generate a codeword; and
discard the first code bit at a beginning of the codeword to produce a shortened codeword; and
a transmitter configured to transmit the shortened codeword in accordance with a wireless technology across a channel via one or more antenna elements (<NUM>) situated proximate the transmitter.