GB2565340A

GB2565340A - A method and devices to support new radio (NR) transmission without grant

Info

Publication number: GB2565340A
Application number: GB1712883.6A
Authority: GB
Inventors: Liu Guang; Marco Olivier
Original assignee: TCL Communication Ltd
Current assignee: TCL Communication Ltd
Priority date: 2017-08-11
Filing date: 2017-08-11
Publication date: 2019-02-13
Anticipated expiration: 2037-08-11
Also published as: CN111226483A; CN111226483B; GB201712883D0; WO2019029591A1; GB2565340B

Abstract

A first wireless communications device transmits a grant-free transmission to a second wireless device including parameters to identify both the device and one or more transmission formats. The transmission formats may be indicated by a HARQ process ID and a redundancy version, and these may be jointly encoded. The second wireless device may be a base station in a 5G (new radio) network such as a gNB. The parameters for identifying the UE may include a UE specific reference sequence such as a demodulation reference symbol sequence (DMRS sequence). They may further include a secondary UE ID comprised of a number of bits, this number having been selected to achieve a target false alarm rate. The secondary UE ID, HARQ process ID and redundancy version may be included in an uplink control information (UCI) signal which may be mapped on to the physical resources by either puncturing or rate matching. The system may find application with MTC or URLLC services.

Description

A method and devices to support New Radio (NR) Transmission without Grant

Technical Field

Embodiments of the present invention generally relate to wireless communication systems and in particular to devices and methods for enabling a wireless communication device, such as a User Equipment (UE) or mobile device to access a Radio Access Technology (RAT) or Radio Access Network (RAN), particularly but not exclusively [B] a method and devices to support NR Uplink (UL) transmission without grant.

Background

Wireless communication systems, such as the third-generation (3G) of mobile telephone standards and technology are well known. Such 3G standards and technology have been developed by the Third Generation Partnership Project (3GPP). The 3rd generation of wireless communications has generally been developed to support macro-cell mobile phone communications. Communication systems and networks have developed towards a broadband and mobile system.

The 3rd Generation Partnership Project has developed the so-called Long Term Evolution (LTE) system, namely, an Evolved Universal Mobile Telecommunication System Territorial Radio Access Network, (E-UTRAN), for a mobile access network where one or more macro-cells are supported by a base station known as an eNodeB or eNB (evolved NodeB). More recently, LTE is evolving further towards the so-called 5G or NR (new radio) systems where one or more cells are supported by a base station known as a gNB.

Normally UL transmission is scheduled by the base station which uses a UL grant message to indicate a terminal which resource can be used for the next UL transmission. This option is called grant based UL transmission. There is another option which does not have a scheduling step before the UL transmission and this option is called grant free UL transmission or UL transmission without grant (both mean the same thing). For UL transmission without grant, a set of resources are preallocated to the terminal for a certain period and the UE can start its transmission without waiting for the downlink scheduling message. Both are illustrated in figure 1 (left: grant based; right: grant free).

For grant based UL transmission, there is at least one Round Trip Time (RTT) delay before the initial transmission and if the amount of data transmitted is very small, the control signalling overhead could be significant. For grant free UL transmission, if the pre-allocated resources are available frequently enough, the latency for initial transmission could be very short but if there is not enough data to occupy all preallocated resources, some resources will be wasted. The advantage and disadvantages of both options are summarized as below in table 1.

Table 1:

For Ultra Reliable Low Latency Communication (URLLC) or Machine Type Communication (MTC), the number of connections could be huge and the amount of data transmitted every time small. In such a case, Scheduling Request (SR) and UL grant together contribute a big signalling overhead and at the same time, both types of services require a short latency and the additional one RTT delay becomes unacceptable. Due to these two reasons, grant free UL transmission is generally selected for URLLC and MTC services.

As mentioned above, grant free transmission must have resources pre-allocated with a certain periodicity and for sporadic services, results in some resources being wasted. In LTE, a similar scheme is adopted, which is called Semi-Persistent Scheduling (SPS). It was introduced to support Voice over Internet Protocol (VoIP) type of services in which the packets arrive with a nearly fixed periodicity and very similar packet size so there is less problems relating to of resource wastage. URLLC is considered to be useful for remotely controlling machines in a factory (factory control) in which the data packets arrive infrequently and sporadically. This may result in a large percentage of pre-allocated resources being wasted. To improve the efficiency, it has been agreed to support multiple UEs sharing the same resources, including grant free only UEs or grant free and grant based UEs. If multiple UEs are sharing the same resources, each of the grant free UEs should be identified

separately and currently De-Modulation Reference Symbol (DMRS) is considered by 3GPP RAN1 for UE identification (UE ID).

In addition to UE identification, several other parameters need to be indicated to the gNB for a proper reception. It has been agreed to support multiple HARQ processes for grant free transmission. As a result, for each transmission, the HARQ process ID needs to be indicated to the gNB if more than one HARQ process is configured. The gNB uses this information to put the received packet in the right buffer or if HARQ soft combining is required, the gNB uses this information to combine the right soft information to improve the reception performance.

It has also been agreed to support transmission repetition. This means the UE can repeat the transmission a number of times as configured by the gNB. Each transmission may or may not use a different Redundancy Version (RV). Thus, RV is another parameter which needs to be indicated for grant free transmission if different RVs are configured.

It has further been agreed that K repetitions are supported, which repetition includes initial transmission (with the same or different RV and still open for decision with different MCS) (K>=1) for the same transport block. K is the number of repetitions.

Thus, UE ID Hybrid Automatic repeater request (HARQ) process ID (HARQ PID in short below) and RV need to be indicated together with the UL grant free transmission. It is possible that parameters like time/frequency allocation, repetition number K, MCS and DMRS sequences, etc., could be (re-)configured by the gNB and according to current agreements, there will more flexible options than SPS in LTE for the gNB to modify parameters or to active/de-active a grant free connection.

The signalling aspects for grant free UL transmission have not been fully agreed. Currently two types have been agreed, one type is to carry out all (re-)configurations and activation/deactivation via Radio Resource Control (RRC) and another type is to do reconfigurations and activation/deactivation via Downlink Control Information (DCI). The second type works like the current SPS procedure in LTE. No matter what the difference is, they are both in the downlink direction and not all signalling issues have been addressed.

From the above discussion, three different parts need to be transmitted for grant free transmission. These are DMRS for channel estimation (and possibly UE identification), control signalling as discussed above, and URLLC data.

Two requirements are identified for URLLC services: for URLLC the target for user plane latency should be 0.5ms for UL, and 0.5ms for DL; and URLLC reliability requirement is one transmission of a packet is 1-10-5 for 32 bytes with a user plane latency of 1ms. Designs of all three parts, i.e., DMRS, control signalling and data, are still open. The URLLC requirements for each part could be supported separately. DMRS pattern and density may to be designed to maximize the overall link performance. Control signalling needs to be the most reliable part as it has no HARQ protection and its one-short detection reliability must be no less than 1-10-5. It should be noted that UE ID, HARQ PID and RV may have different reliability requirements. The data part has HARQ protection so its one-short detection reliability reduced as far as the final reliability of 1-10-5 can be achieved with HARQ retransmission.

To enable grant free UL transmission, multiple signalling options have been proposed. These will now be described below.

In a first option, DMRS is considered to indicate UE ID, specific DMRS sequence can be configured to a UE and the gNB can identify the UE by detecting the corresponding DMRS sequence. It may be possible to extend this option to let DMRS further support HARQ PID and/or RV. In that case, multiple DMRS sequences may need to be configured to a UE. This option may have a detection reliability problems especially when the resources are multiplexed with enhanced Mobile Broadband (eMBB) UEs. Due to power control of the multiplexed eMBB UE, the interference at the gNB could be very different and the gNB may need to select a threshold with the worst case for the detection which will in return reduce the DMRS detection reliability. The eMBB modulated symbols may be correlated to the URLLC DMRS symbols and in such a case, a false alarm may be produced. Due to these drawbacks, it is assumed that it is even harder for DRMS to indicate HARQ PID and/or RV.

In a second option, it was proposed that different HARQ processes may be mapped to different time/frequency resources. Multiple resources may be pre-allocated to a UE, and the UE selects the resource with the HARQ process ID for the transmission.

It may be possible to extend this option to let different resource indicate RV as well. This option requires multiple resources are pre-allocated. On one hand, this may further decrease the resource usage efficiency, and on another hand, it may not support many HARQ processes in the frequency domain as URLLC services normally require a wide band. It may further increase the latency when multiple resources are allocated in the time domain as discussed in the example given below with reference to figure 2.

Assuming, three HARQ processes are mapped to three mini-slot sets, i.e., mini-slot #0, 3, 6... for HARQ PID #0, mini-slot #1, 4, 7... for HARQ PID #1 and mini-slot #2, 5, 8... for HARQ PID #2. When a packet arrives in Buffer #0 (must be transmitted with HARQ PID #0), the UE cannot transmit it in the first available mini-slot (#4 in this example) and has to skip two mini-slots until mini-slot #6. This introduces an additional latency of two mini-slots.

In a third option it was proposed that HARQ PID to UL Control Information (UCI) be introduced, which can be transmitted together with UL data. It may be possible to extend this option to include RV. This option requires the introduction of a new type of UCI. This new type of UCI has a different reliability requirement from others and more standardization efforts are required. Currently in LTE, UCI only includes signalling for downlink (DL) transmissions. RV and HARQ PID are both UL associated parameters. As Discrete Fourier Transform (DFT)-scalable Orthogonal Frequency Division Multiplexing (S-OFDM) waveform only is supported in LTE UL, UCI is multiplexed with Physical Uplink Shared Channel (PUSCH) in the time domain if is piggybacks on top of PUSCH. As a result, a new UCI with RV and HARQ PID needs to be multiplexed in frequency domain with a Cyclic Prefix (CP)-OFDM waveform supported.

If UCI is to be carried by Physical Uplink Control Channel (PUCCH), there might also be inter-modulation issues with an extra out-band emission when it is transmitted simultaneously with PUSCH but with discontinuous resources allocation and as a result, power back off needs to be used which will harm the UL transmission reliability in the end.

These above-mentioned options support HARQ PID and similar options may be used for RV.

In the cooperation from RAN4 to RAN1, it has been clarified that Sub-Carrier Spacing (SCS) of 15 KHz, 30 KHz and 60 KHz are supported for sub-6GHz band. Since URLLC requires an extremely high reliability, it should also be supported in sub-6GHz band so it can be concluded that URLLC services will be supported with SCS of 15 KHz, 30 KHz and 60 KHz. As shown in Figure 3, there are possibly 3 cases, i.e., mini-slot (2 symbols) for 15 KHz SCS, mini-slot (4 symbols) for 30 KHz SCS and 7-symbol slot for 60 KHz SCS. Their design and evaluation are similar and in this disclosure, mini-slot of 2 symbols with 15 KHz SCS is used as an example to show the design and corresponding evaluation results.

The present invention is seeking to solve at least some of the outstanding problems in this domain.

Summary

This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

According to a first aspect of the present invention there is provided a method for enabling a wireless communication device to access services provided by a Radio Access Network, the method comprising: identifying a transmission of a first wireless communications device, which transmits a grant free transmission to a second wireless communications device, wherein parameters are included for identification of at least one of the first wireless communication device and one or more transmission formats.

Preferably, the identification comprises detecting a UE specific reference sequence and a secondary UE ID received in a transmission.

Preferably, the UE specific reference sequence is carried by one of a demodulation reference symbols, a pilot symbol and a preamble symbols.

Preferably, the secondary UE ID is related to one of a full set or a subset of a complete UE ID.

Preferably, the secondary UE ID bits are indicated by the second wireless communications device.

Preferably, the secondary UE ID bits are obtained by the first wireless communications device from one or more parameters according to a pre-defined method.

Preferably, the number of the secondary UE ID bits is selected according to a gap size from an actually false alarm rate to a pre-defined target false alarm rate.

Preferably, the secondary UE ID and/or the jointly encoded HARQ process ID and redundancy version are included in an uplink control information signal.

Preferably, the UCI is mapped to the physical resources by at least one of puncturing and rate matching a data part.

Preferably, the one or more transmission formats is indicated by at least one of a HARQ process ID and a redundancy version.

Preferably, the HARQ process ID and redundancy version are jointly encoded.

Preferably, combinations of all possible HARQ process ID values and all possible redundancy version values are encoded.

Preferably, the Radio Access Network is a New Radio/5G network.

According to a second aspect of the present invention there is provided a base station adapted to perform the method of another aspect of the present invention.

According to a third aspect of the present invention there is provided a UE adapted to perform the method of another aspect of the present invention.

According to a fourth aspect of the present invention there is provided a non-transitory computer readable medium having computer readable instructions stored thereon for execution by a processor to perform the method of another aspect of the present invention.

The non-transitory computer readable medium may comprise at least one from a group consisting of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read Only Memory, a Programmable Read Only Memory, an Erasable Programmable Read Only Memory, EPROM, an Electrically Erasable Programmable Read Only Memory and a Flash memory.

Brief description of the drawings

Further details, aspects and embodiments of the invention will be described, by way of example only, with reference to the drawings. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. Like reference numerals have been included in the respective drawings to ease understanding.

Figure 1 is a simplified diagram showing UL grant-based and grant-free transmissions, according to the prior art.

Figure 2 is a simplified diagram showing additional latency of two mini-slots, according to the prior art.

Figure 3 is a simplified diagram showing three possible options for signalling, according to the prior art.

Figure 4 is a simplified diagram showing UCI carrying HARQ PID and RV, according to an embodiment of the present invention

Figure 5 is a simplified diagram showing the modulation order of data symbol, according to an embodiment of the present invention.

Figure 6 is a simplified diagram showing part or full UE ID included in the UCI, according to an embodiment of the present invention.

Figure 7 is a simplified graph showing URLLC performance compared with DMRS patterns, according to an embodiment of the present invention.

Figure 8 is a simplified diagram showing a processing procedure, according to an embodiment of the present invention.

Detailed description of the preferred embodiments

Those skilled in the art will recognise and appreciate that the specifics of the examples described are merely illustrative of some embodiments and that the teachings set forth herein are applicable in a variety of alternative settings.

This invention discloses a method to support UL transmission without grant, and more specifically, it is about how a set of parameters is indicated to support the gNB to process the UL transmission.

In broad terms, the invention include three main attributes. By jointly encoding RV and HARQ PID, the overall size of UL signalling can be minimized and accordingly less UL resources will be consumed and the reliability of UL data transmission can be improved. By piggybacking the UCI on PUSCH, the resource allocation of UL grant free transmission can be simplified and no dedicated resources need to be allocated for signalling. Piggybacking can also help to reduce the out-band emissions by supporting continuous resources usage. By adding a secondary UE ID, a false alarm rate of DMRS detection can be reduced and it may enhance the UE identification reliability for URLLC transmissions.

The number of RVs and HARQ processes required for URLLC and for eMBB is open for discussion, but is likely to include eight HARQ processes for very high throughputs. The number of RV is likely to be the same as in LTE, i.e. 4RVs.

There may be a variety of URLLC services and depending on the throughput and reliability requirements, a different number of HARQ processes and RVs can be configured for a particular URLLC connection. Joint encoding will reduce the overall signalling size. For example, when three RVs and five HARQ processes are configured for a UE, a total of five bits are required but joint encoding can reduce this to four bits. Thus with a smaller signalling size, more resources could be used for data to achieve a better reliability. This is shown by way of example in table 2.

Table 2.

The jointly encoded bits can be carried by a combination of any two or all of the three (first, second and third) options mentioned above. An example is given below with all three options combined.

For the 4 encoded bits of the example shown in table 2 above, the first bit, could be carried by whichever resource is used. The two sets of resources are configured to the UE, e.g., two 10MHz sub-bands of 20MHz band. The value of this bit is indicated by whichever set of resources is used for transmission. The second bit, is carried by whichever DMRS sequence is used and two sequences are configured to the UE so both sequences can be used to identify this UE. Simultaneously, the value of this bit can be indicate by selecting the corresponding sequence. The remaining two bits (third and fourth) are carried in UCI. UCI for grant free transmission could be carried out in a similar way to LTE. One way is to use a piggyback with PUSCH and the other way is to be carried in PUCCH. The option to use piggyback with PUSCH is detailed below and forms part of the present invention.

It is assumed that all configurations mentioned above are indicated to the UE via RRC or DCI signalling. One example is for the gNB to allocate a number of different resource sets, a number of DMRS sequences and a number of UCI bits. Different resources are used in a pre-defined order to carry the jointly encoded bits. At the

same time, the number of RVs and the number HARQ processes are also indicated via RRC and/or L1 signalling.

Referring to figure 4, a scheme in which UCI carrying HARQ PID and RV is piggybacked by puncturing, or rate matching the PUSCH, is shown.

Similar designs as are used in LTE can be used this scheme. For a mini-slot of two symbols, modulated DMRS symbols are first mapped to predefined Resource Block (RB) positions. Encoded and modulated UCI symbols are mapped to certain RB positions to insure a better link performance. The best positions for UCI are those around the DMRS and encoded and modulated UCI symbols function mapped to these positions has better results. Encoded and modulated data symbols are mapped to all the remaining RB positions. Here each RB position includes 12 subcarriers in the frequency domain and 1 symbol in the time domain. The above example, does not preclude that a different RB size might be defined, e.g., a resource block of 12 subcarriers by 2 symbols or subcarriers of a RB could be multiplexed between DMRS, UCI and data even if the same RB size is used. For example, 6 subcarriers for UCI and the remaining 6 subcarriers for data. See the symbol scheme of figure 5 by way of example.

For UCI, there might be no rate matching as the UCI may have a fixed payload size and the modulation order could be fixed too, e.g., Quadrature Phase Shift Keying (QPSK). Normally rate matching is used when the amount of physical resources is not fixed, or the physical resources are fixed but the payload size is not fixed. For UCI, its payload size could be fixed and it is mapped to the physical resources with a higher priority so there is less need to do rate matching. The modulation order of data symbol may be indicated by downlink control signalling, either RRC or DCI. Note, it is assumed the CP-OFDM waveform is used in the figure 4 scheme and if the DFT-s-OFDM waveform is used, all 3 parts (DMRS, UCI and data) may be mapped to the physical layer in the time domain.

In an alternative scheme, part or full UE ID is included in the UCI to improve the reliability of DMRS detection

As illustrated in figure 6, first an UL transmission with a mini-slot of 2 symbols is simulated with a number of different DMRS patterns (corresponding to different DMRS densities). In figure 6, the following five patterns are evaluated. Pattern #0 has 1 OFDM symbol fully used for DMRS so the DMRS density equals 1/2. Pattern #1 has one RB used for DMRS from every two in the first OFDM symbol and all RBs in the second symbol are used for data so the DMRS density equals 1/4. Pattern #2 has one RB from every 3 RBs used for DMRS in the first symbol and Pattern #3 and Pattern #4 have one RB from every 4 and 5 RBs separately used for DMRS with corresponding DMRS density equals 1/8 and 1/10 respectively.

Without considering UCI, 32 bytes payload (including 2 bytes CRC) is encoded with Tail-biting Convolutional Codes (TBCC), LTE PUCCH like rate matching is used, modulated with QPSK and then mapped to the remaining RBs of 10 MHz bandwidth except those used for DMRS. Rate matching is applied accordingly for each DMRS pattern which means a lower coding rate with lower DMRS density and a high coding rate with higher DMRS density. With higher DMRS density, a better channel estimation results can be achieved but less resources for data, less accumulated power for data symbols. The DMRS density needs to be selected with a trade-off between channel estimation and data resources. The optimal DMRS density could be different for 15 KHz, 30 KHz and 60 KHz SCS and may be evaluated separately.

As discussed above and as demonstrated in figure 7, URLLC data has HARQ protection and 1-10-3 reliability is acceptable if one retransmission can be achieved within the given latency budget. In that case, the required Signal to noise Ratio (SNR) is around 9dB. The DMRS detection probability is evaluated below with SNR = 9dB. Note that 9dB is only valid with the assumptions used in this example, and when conditions change, a different SNR might be used.

The DMRS detection is based on a threshold and this threshold is selected with a trade-off between false alarm rate (FAR) and detection rate. False alarm rate is the probability of detection when nothing is actually transmitted by a UE, a false alarm will result in resource waste for both downlink control channel and uplink data channel, and 1% threshold might be an acceptable value.

From the graph it can be seen that a DMRS density of 1/6 has the best link performance. Detection probabilities for the three DMRS patterns are given in the table 3.

Table 3:

To tolerate the received power variety, the cross correlation value is normalized by the power of the second symbol. It is observed that different DMRS patterns do not have a significant difference in detection performance

As shown in the above table 3, by decreasing the detection threshold, the detection probability can be improved from 99.97x% to 99.999% with the cost of the false alarm rate being increased from 1% to 1.7x%. Based on this set of results, a 1-bit secondary UE ID can be included in the UCI to verify the UE ID obtained from the DMRS detection and the final false alarm rate can be halved (0.9% = 1.80%/2) with this additional bit. The secondary UE ID could be a segment of the normal UE ID, e.g., Cell Radio Network Temporary Identity (C-RNTI), or a completely different one which is used to verify the validity of the one detected from DMRS sequence if applicable.

Depending on the gap between the actual FAR and target FAR, a number of secondary UE ID bits can be included in the UCI, for instance, the actual FAR = 1.7% is less than twice of the target FAR = 1% so a single bit UE ID can help to eliminate the gap. In short, the number of secondary UE ID bits included in the UCI is selected according the need to reduce the FAR. The actual FAR from DMRS detection is related to the DMRS density and vender specific algorithm, so the number of secondary UE ID bits to be included in the UCI needs to be aligned between the gNB and the UE.

The actual secondary UE ID bits could be obtained from a number of different processes. For example, explicit signalling from the gNB, in which the gNB can indicate in the RRC the number of secondary UE ID bits and the corresponding values. Alternatively implicitly from other configured parameters, for instance, the last few bits of C-RNTI assigned by the gNB, or a set of bits pre-determined for the assigned DMRS sequence. In another example, the number of secondary UE ID bits could be signalled by the gNB but their values are implicitly obtained. This can be

summarize as the following three options: size and value are both signalled by the gNB; size and value are both implicitly obtained from other configured parameters; and size is signalled by the gNB, and the actual value is obtained from other configured parameters. A number of examples are given below and the following assumptions are made: four UEs (UE #0, UE #1, UE #2 and UE #3), are assigned to the same resources and each of them can be identified as indicated. In a first scheme, UE #i uses DMRS sequence #i, a secondary UE ID of 2 bits are included in the UCI to reduce the FAR and a UE can be identified by DMRS sequence #i + a dedicated value of the partial UE ID. In a second scheme, UE #i uses DMRS sequence #i, a secondary UE ID of 1 bit is included in the UCI to reduce the FAR (every two UEs have the same partial UE ID) and each UE can be identified by DMRS sequence #i + a dedicated value of the partial UE ID. In a third scheme, all UEs use the same DMRS sequence and each UE is identified only by a dedicated value of the partial UE ID. In a fourth scheme, some UEs could share the same DMRS sequence and each UE can be identified by DMRS sequence index + a dedicated value of the partial UE ID.

For all the above examples, the secondary UE ID can be either signalled by the gNB via RRC and/or L1 signalling or obtained from a pre-defined mapping with the DMRS sequence when possible, for instance, in Example #1, the secondary UE ID is the last two bits of the DMRS sequence index. The various combinations are shown in table 4.

Table 4:

Note that the simulation has not considered multiple DMRS sequences and when there are multiple cross correlator peaks from any correlator with only noise or interference input will trigger a false alarm so the false alarm rate will be increased. It is expected that with N cross correlators, the false alarm rate will be N times higher.

With false alarm increased, the number of (partial) UE ID bits will also be to be increased.

The UE may transmit DMRS, UCI and data without grant. The DMRS sequence may be pre-configured by the gNB, and UCI may include a number of secondary UE ID bits, RV and/or HARQ PID. The data part may be encoded and modulated with an MCS which is also pre-configured by the gNB. These options are examples and may be varied in other ways as will be evident to those skilled in the art.

An example processing procedure is illustrated in figure 8 for the gNB side. The gNB first identifies a UE by detecting the corresponding DMRS sequence and the peak of multiple cross correlators’ outputs is selected and compared against a threshold. If the peak is above the threshold, a UE is assumed to be temporally identified and after the UCI is decoded, this temporal UE ID is verified by the secondary UE ID bit or bits from the UCI. If both match, the gNB will assume a real transmission is detected otherwise it will assume no UL transmission. If the detected UE ID and the secondary UE ID bits match, the receiver can further use the modulated UCI symbols to improve the channel estimation and as a result, the link performance of the data part can be further improved.

The present invention has been described with reference to UL transmission is a certain environment. It will be appreciated that the present invention may equally apply to other types of transmission in other environments. For example: device to device communications, vehicle to vehicle communications and machine to machine communications when a device (vehicle or machine) is jointly identified by a pilot (preamble or reference symbol) and a separately encoded UE ID.

Although not shown in detail any of the devices or apparatus that form part of the network may include at least a processor, a storage unit and a communications interface, wherein the processor unit, storage unit, and communications interface are configured to perform the method of any aspect of the present invention. Further options and choices are described below.

The signal processing functionality of the embodiments of the invention especially the gNB and the UE may be achieved using computing systems or architectures known to those who are skilled in the relevant art. Computing systems such as, a desktop, laptop or notebook computer, hand-held computing device (PDA, cell phone, palmtop, etc.), mainframe, server, client, or any other type of special or general purpose computing device as may be desirable or appropriate for a given application or environment can be used. The computing system can include one or more processors which can be implemented using a general or special-purpose processing engine such as, for example, a microprocessor, microcontroller or other control module.

The computing system can also include a main memory, such as random access memory (RAM) or other dynamic memory, for storing information and instructions to be executed by a processor. Such a main memory also may be used for storing temporary variables or other intermediate information during execution of instructions to be executed by the processor. The computing system may likewise include a read only memory (ROM) or other static storage device for storing static information and instructions for a processor.

The computing system may also include an information storage system which may include, for example, a media drive and a removable storage interface. The media drive may include a drive or other mechanism to support fixed or removable storage media, such as a hard disk drive, a floppy disk drive, a magnetic tape drive, an optical disk drive, a compact disc (CD) or digital video drive (DVD) read or write drive (R or RW), or other removable or fixed media drive. Storage media may include, for example, a hard disk, floppy disk, magnetic tape, optical disk, CD or DVD, or other fixed or removable medium that is read by and written to by media drive. The storage media may include a computer-readable storage medium having particular computer software or data stored therein.

In alternative embodiments, an information storage system may include other similar components for allowing computer programs or other instructions or data to be loaded into the computing system. Such components may include, for example, a removable storage unit and an interface , such as a program cartridge and cartridge interface, a removable memory (for example, a flash memory or other removable memory module) and memory slot, and other removable storage units and interfaces that allow software and data to be transferred from the removable storage unit to computing system.

The computing system can also include a communications interface. Such a communications interface can be used to allow software and data to be transferred between a computing system and external devices. Examples of communications interfaces can include a modem, a network interface (such as an Ethernet or other NIC card), a communications port (such as for example, a universal serial bus (USB) port), a PCMCIA slot and card, etc. Software and data transferred via a communications interface are in the form of signals which can be electronic, electromagnetic, and optical or other signals capable of being received by a communications interface medium.

In this document, the terms ‘computer program product’, ‘computer-readable medium’ and the like may be used generally to refer to tangible media such as, for example, a memory, storage device, or storage unit. These and other forms of computer-readable media may store one or more instructions for use by the processor comprising the computer system to cause the processor to perform specified operations. Such instructions, generally referred to as ‘computer program code’ (which may be grouped in the form of computer programs or other groupings), when executed, enable the computing system to perform functions of embodiments of the present invention. Note that the code may directly cause a processor to perform specified operations, be compiled to do so, and/or be combined with other software, hardware, and/or firmware elements (e.g., libraries for performing standard functions) to do so.

The non-transitory computer readable medium may comprise at least one from a group consisting of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read Only Memory, a Programmable Read Only Memory, an Erasable Programmable Read Only Memory, EPROM, an Electrically Erasable Programmable Read Only Memory and a Flash memory

In an embodiment where the elements are implemented using software, the software may be stored in a computer-readable medium and loaded into computing system using, for example, removable storage drive. A control module (in this example, software instructions or executable computer program code), when executed by the processor in the computer system, causes a processor to perform the functions of the invention as described herein.

Furthermore, the inventive concept can be applied to any circuit for performing signal processing functionality within a network element. It is further envisaged that, for example, a semiconductor manufacturer may employ the inventive concept in a design of a stand-alone device, such as a microcontroller of a digital signal processor (DSP), or application-specific integrated circuit (ASIC) and/or any other sub-system element.

It will be appreciated that, for clarity purposes, the above description has described embodiments of the invention with reference to a single processing logic. However, the inventive concept may equally be implemented by way of a plurality of different functional units and processors to provide the signal processing functionality. Thus, references to specific functional units are only to be seen as references to suitable means for providing the described functionality, rather than indicative of a strict logical or physical structure or organisation.

Aspects of the invention may be implemented in any suitable form including hardware, software, firmware or any combination of these. The invention may optionally be implemented, at least partly, as computer software running on one or more data processors and/or digital signal processors or configurable module components such as FPGA devices. Thus, the elements and components of an embodiment of the invention may be physically, functionally and logically implemented in any suitable way. Indeed, the functionality may be implemented in a single unit, in a plurality of units or as part of other functional units.

Although the present invention has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the present invention is limited only by the accompanying claims. Additionally, although a feature may appear to be described in connection with particular embodiments, one skilled in the art would recognize that various features of the described embodiments may be combined in accordance with the invention. In the claims, the term ‘comprising’ does not exclude the presence of other elements or steps.

Furthermore, although individually listed, a plurality of means, elements or method steps may be implemented by, for example, a single unit or processor. Additionally, although individual features may be included in different claims, these may possibly be advantageously combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. Also, the inclusion of a feature in one category of claims does not imply a limitation to this category, but rather indicates that the feature is equally applicable to other claim categories, as appropriate.

Furthermore, the order of features in the claims does not imply any specific order in which the features must be performed and in particular the order of individual steps in a method claim does not imply that the steps must be performed in this order. Rather, the steps may be performed in any suitable order. In addition, singular references do not exclude a plurality. Thus, references to ‘a’, ‘an’, ‘first’, ‘second’, etc. do not preclude a plurality.

Although the present invention has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the present invention is limited only by the accompanying claims. Additionally, although a feature may appear to be described in connection with particular embodiments, one skilled in the art would recognise that various features of the described embodiments may be combined in accordance with the invention. In the claims, the term ‘comprising’ or “including” does not exclude the presence of other elements.

Claims

1. A method for enabling a wireless communication device to access services provided by a Radio Access Network, the method comprising: identifying a transmission of a first wireless communications device, which transmits a grant free transmission to a second wireless communications device, wherein parameters are included for identification of at least one of the first wireless communication device and one or more transmission formats.

2. The method as claimed in claim 1, wherein the identification comprises detecting a UE specific reference sequence and a secondary UE ID received in a transmission.

3. The method as claimed in claim 2, wherein the UE specific reference sequence is carried by one of a demodulation reference symbols, a pilot symbol and a preamble symbols.

4. The method as claimed in claim 2 or claim 3, wherein the secondary UE ID is related to one of a full set or a subset of a complete UE ID.

5. The method as claimed in claim 4, wherein the secondary UE ID bits are indicated by the second wireless communications device.

6. The method as claimed in claim 4, wherein the secondary UE ID bits are obtained by the first wireless communications device from one or more parameters according to a pre-defined method.

7. The method as claimed in claim 5 or claim 6, wherein the number of the secondary UE ID bits is selected according to a gap size from an actually false alarm rate to a pre-defined target false alarm rate.

8. The method as claimed in any of claim 4 to claim 7, wherein the secondary UE ID and/or the jointly encoded HARQ process ID and redundancy version are included in an uplink control information signal.

9. The method as claimed in claim 8, wherein the UCI is mapped to the physical resources by at least one of puncturing and rate matching a data part.

10. The method as claimed in any one of the preceding claims, wherein the one or more transmission formats is indicated by at least one of a HARQ process ID and a redundancy version.

11. The method as claimed in claim 10, wherein the HARQ process ID and redundancy version are jointly encoded,

12. The method of claim 10 or claim 11, wherein combinations of all possible HARQ process ID values and all possible redundancy version values are encoded;

13. The method of any one of the preceding claim wherein the Radio Access Network is a New Radio/5G network.

14. A user equipment, UE, apparatus comprising a processor, a storage unit and a communications interface, wherein the processor unit, storage unit, and communications interface are configured to perform the method as claimed in any one of claims 1 -13.

15. A base station, BS, apparatus comprising a processor, a storage unit and a communications interface, wherein the processor unit, storage unit, and communications interface are configured to perform the method as claimed in any one of claims 1 -13

16. A non-transitory computer readable medium having computer readable instructions stored thereon for execution by a processor to perform the method according to any of claims 1-13.