Patent Description:
For cellular communications, especially in the uplink (UL), it is important to maintain a low Peak-to-Average-Power Ratio/Cubic Metric (PAPR/CM) of the transmitted signal for less power backoff in the amplifier. This in turn offers better coverage and less power consumption of the user device. Multi-carrier signals, such as Orthogonal Frequency Division Multiplexing (OFDM), are known to exhibit rather large PAPR/CM. One method used in Long Term Evolution (LTE) uplink for reducing the PAPR/CM is to apply a Discrete Fourier Transform (DFT) precoder, which applied prior to the Inverse Fast Fourier Transform (IFFT) operation, produces a Single Carrier - Frequency Division Multiple Access (SC-FDMA) signal.

In LTE uplink, the control channel, Physical Uplink Control Channel (PUCCH), is conveying Uplink Control information (UCI), e.g., Hybrid Automatic Repeat reQuest-ACKnowledgement (HARQ-ACK), Channel State Information (CSI) and Scheduling Request (SR), by using different PUCCH formats. The PUCCH formats are distinguished by their payload capacities as well as other properties, e.g., some are based on modulated sequences while some are DFT precoded and some are capable of Code Division Multiplexing (CDM) among User Equipments (UEs). PUCCH formats <NUM>/1a/1b/<NUM>/2a/2b/<NUM>/<NUM> are transmitted in one Physical Resource Block (PRB) pair (i.e., one PRB in the first slot and one PRB in the second slot of a subframe), and PUCCH format <NUM> is transmitted with one, or more than one, PRB pair(s) per slot. For PUCCH format <NUM>, the transmission is made in one cluster of one or multiple PRBs contiguously located in the frequency domain within a slot. This assures low PAPR/CM. Furthermore, for all PUCCH formats, frequency hopping is used between the two slots in a subframe for the PRB pairs, such that the PRBs are located towards different edges of the carrier in the two slots.

LTE can also be deployed for transmissions in unlicensed spectrum with carrier aggregation, i.e., utilizing Licensed Assisted Access (LAA) where an unlicensed carrier is operated as a Secondary cell (SCell) in conjunction with a Primary cell (PCell) located in licensed spectrum.

For LAA, a first regulatory requirement is that the occupied channel bandwidth shall be between <NUM>% and <NUM>% of the declared nominal channel bandwidth. The occupied channel bandwidth is the bandwidth containing <NUM>% of the power of the signal. This requirement does not mandate that only a single UE can occupy <NUM>-<NUM>% of the carrier bandwidth. For example, it would be possible to multiplex PUCCHs from several UEs in an UL subframe over the whole carrier bandwidth using some form of interleaved Frequency Division Multiplex (FDM) allocation, while fulfilling the occupied channel bandwidth requirement. In addition, a second regulatory requirement is the maximum transmission power in a narrow band. For example, in the frequency band <NUM>-<NUM>, transmissions shall be limited to a maximum mean Equivalent Isotropically Radiated Power (EIRP) density of <NUM> mW/MHz in any <NUM> band. This implies that, in order not to limit the transmit power, it is beneficial to allocate the resources in as many '<NUM>' bands as possible.

A PUCCH being transmitted in frequency localized manner may not fulfill the bandwidth occupancy requirement, since it may not span a sufficient bandwidth in any given slot. In order to efficiently meet the bandwidth requirement, extending the current single cluster allocation to allow multi-cluster (><NUM>) allocation (e.g., PRBs spaced uniformly in frequency) has been identified as a candidate waveform for PUCCH. The LTE PUCCH formats, e.g., PUCCH formats <NUM>/1a/1b/<NUM>/2a/2b/<NUM>/<NUM>, occupy only one PRB pair in the frequency domain, which does not fit into the multi-cluster PUCCH resource with multiple PRB pairs. It would still be desirable if the multi-cluster PUCCH could be based on existing LTE PUCCH formats, e.g., PUCCH formats <NUM>/<NUM>/<NUM>, which can carry sufficiently large payloads while benefitting from low PAPR/CM due to DFT precoding. This would be advantageous since much of the receiver and transmitter processing of the PUCCH could be reused. Furthermore, the multi-cluster PUCCH should preferably be designed for low PAPR/CM to avoid power backoff which could imply coverage limitation.

An objective of implementations of the disclosure is to provide a solution which mitigates or solves the drawbacks and problems of conventional solutions.

The above and further objectives are achieved by the subject matter of the independent claims.

Further advantageous implementation forms of the invention are defined by the dependent claims.

The disclosure has been defined in the independent claims.

The expression "the first set and the second set differ from each other in at least one modulation symbol" should be understood that it includes that at least one modulation symbol/bit is different among the two sets. Further, it should be noted that at least a first set of modulation symbols and a second set of modulation symbols are provided. This implies that at least two sets of modulation symbols are provided meaning that the cases of three sets, four sets, five sets, and so forth, are also covered by implementations of the disclosure.

Mapping may mean allocating or assigning modulation symbols to time-frequency resources, e.g., REs, subcarriers, etc..

A sub-band is a part of the whole transmission bandwidth. Therefore, the transmission bandwidth of the system is divided into a plurality of sub-bands. A sub-band could comprise a number of PRBs or REs and sub-bands may be of same or different size.

A transmitting device according to the first aspect provides a number of advantages over conventional transmitting devices. In particular it can provide an uplink control channel which can be transmitted on a non-contiguous multi-cluster resource structure with a large number of PRBs, while reusing the main features of existing PUCCH formats and providing low CM/PAPR performance. Thereby, it can provide a certain percentage of channel bandwidth occupancy, good PAPR/CM performance and low complexity by leveraging existing uplink control channel structures.

Scrambling may mean a bit-wise addition modulo <NUM> of the bits representing the control information and the scrambling sequence.

An advantage of scrambling using sub-band specific scrambling sequences is the low-complexity as it does not require any multiplications due to the modulo addition operation. It also requires minimum change to existing PUCCH formats as only the input bit sequence is modified and therefore reduces the cost and implementation complexity of the transmitter and receiver.

Use of a pseudo random sequence is advantageous as it provides good randomization while being able to provide different scrambling sequences being generated from one pseudo-random sequence by just using different initial states in the scrambling sequence generator.

An advantage of cyclic shifting is the low complexity as it does not require any multiplications of the modulation symbols. It also requires minimum change to existing PUCCH formats and therefore reduces the cost and implementation complexity of the transmitter and receiver.

An advantage of interleaving is the low complexity as it does not require any multiplications of the modulation symbols. It also requires minimum change to existing PUCCH formats and therefore reduces the cost and implementation complexity of the transmitter and receiver.

An advantage of DFT precoding is that the PAPR/CM can be reduced.

An advantage of using sub-band specific DFT precoding is that it follows the structure of single-cluster PUCCH formats in LTE, which allows reusing much of the transmitter and receiver processing per sub-band.

An advantage of using a single DFT precoder for all sub-bands is that the CM/PAPR can be made very low.

A corresponding set could refer to that the resulting resource allocation is the same within the first sub-band and within the second sub-band. It should be noted that the sets may contain different resource indices, e.g., different PRB indices if the PRBs are enumerated over both sub-bands, but the resulting resource allocation becomes the same in both sub-bands.

Further applications and advantages of implementations of the disclosure will be apparent from the following detailed description.

The appended drawings are intended to clarify and explain different implementations of the disclosure, in which:.

To make the objectives, technical solutions, and advantages of this disclosure clearer, the following further describes the implementations of this disclosure in detail with reference to the accompanying drawings. The implementations described below are not all claimed, they are included to help understanding the context of the disclosure. Any implementation which does not fall within the scope of the claims does not form part of the disclosure, but rather included as an illustrative example that is useful for understanding the disclosure.

<FIG> shows a transmitting device <NUM> according to an implementation of the disclosure. The transmitting device <NUM> comprises a signal processor <NUM> configured to modulate bits representing control information for providing at least a first set of modulation symbols M1 and a second set of modulation symbols M2. The signal processor <NUM> is configured to provide a first set of mapped modulation symbols M1' by mapping the first set of modulation symbols M1 onto a set of frequency resources R within a first sub-band. The signal processor <NUM> is configured to provide a second set of mapped modulation symbols M2' by mapping the second set of modulation symbols M2 onto a corresponding set of frequency resources R' within a second sub-band. According to implementations of the disclosure the first set of mapped modulation symbols M1' and the second set of mapped modulation symbols M2' differ from each other in at least one modulation symbol, and further the first sub-band and the second sub-band are non-overlapping.

In an implementation the transmitting device <NUM> is part of, or integrated in a user device <NUM> which is also shown in <FIG>. Hence, the control information may in this particular case be UCI, and comprising HARQ-ACK, CSI, and SR, by using different PUCCH formats known in the art.

The user device <NUM> comprises a transmitter/transceiver <NUM> coupled to an antenna <NUM> configured to transmit in the wireless communication system <NUM>. Therefore, the signal processor <NUM> is configured to generate a control signal Sc based on the first set of mapped modulation symbols M1' and the second set of mapped modulation symbols M2'. The signal processor <NUM> is also configured to forward the control signal Sc to the transmitter <NUM>. The transmitter <NUM> is configured to transmit the control signal Sc using the set of frequency resources R within a first sub-band and the corresponding set of frequency resources R' within the second sub-band, see <FIG> for the allocation of the frequency resources R and R', respectively.

The user device <NUM>, which may be any of a User Equipment (UE), mobile station (MS), wireless terminal or mobile terminal, is enabled to communicate wirelessly in a wireless communication system, sometimes also referred to as a cellular radio system. The UE may further be referred to as mobile telephones, cellular telephones, computer tablets or laptops with wireless capability. The UEs in the present context may be, for example, portable, pocket-storable, hand-held, computer-comprised, or vehicle-mounted mobile devices, enabled to communicate voice or data, via the radio access network, with another entity, such as another receiver or a server. The UE can be a Station (STA), which is any device that contains an IEEE <NUM>-conformant Media Access Control (MAC) and Physical Layer (PHY) interface to the Wireless Medium (WM).

<FIG> shows a corresponding method <NUM> which may be executed in a transmitting device <NUM>, such as the one shown in <FIG>. The method <NUM> comprises modulating <NUM> bits representing (uplink) control information for providing at least a first set of modulation symbols M1 and a second set of modulation symbols M2. The method <NUM> further comprises providing <NUM> a first set of mapped modulation symbols M1' by mapping the first set of modulation symbols M1 onto a set of frequency resources R within a first sub-band. The method <NUM> further comprises providing <NUM> a second set of mapped modulation symbols M2' by mapping the second set of modulation symbols M2 onto a corresponding set of frequency resources R' within a second sub-band. According to the present solution the first set of mapped modulation symbols M1' and the second set of mapped modulation symbols M2' differ from each other in at least one modulation symbol.

According to the present solution the first sub-band and the second sub-band are non-overlapping.

<FIG> shows a receiving device <NUM> according to an implementation of the disclosure. The receiving device <NUM> comprises a receiver <NUM> communicably coupled to a signal processor <NUM>. The receiver <NUM> is configured to receive a control signal Sc associated with a transmitting device <NUM>. The control signal Sc comprises at least a first set of modulation symbols M1 mapped onto a set of frequency resources R within a first sub-band, and a second set of modulation symbols M2 mapped onto a corresponding set of frequency resources R' within a second sub-band. According to implementations of the disclosure the first set of mapped modulation symbols M1' and the second set of mapped modulation symbols M2' differ from each other in at least one modulation symbol and each set of mapped modulation symbols M1' and M2' are associated with the control information. The signal processor <NUM> is configured to derive the control information based on the control signal Sc.

In an implementation, the signal processor <NUM> is configured to derive the control information based on at least the first set of mapped modulation symbols M1' and the second set of mapped modulation symbols M2'. This means that at least two sets of mapped modulation symbols are used in this respect for improved performance.

In a further implementation, the receiving device <NUM> is part of, or integrated in a network node <NUM> which is also shown in <FIG>. Hence, the control information associated with the transmitting device <NUM> may in this case be UCI and may comprise HARQ-ACK, CSI, and SR, by using different PUCCH formats.

In this disclosure a network node <NUM> may refer to a network control node or a network access node or an access point or a base station, e.g., a Radio Base Station (RBS), which in some networks may be referred to as transmitter, "eNB", "eNodeB", "NodeB" or "B node", depending on the technology and terminology used. The network nodes may be of different classes such as, e.g., macro eNodeB, home eNodeB or pico base station, based on transmission power and thereby also cell size. The network node can be an <NUM> access point or a Station (STA), which is any device that contains an IEEE <NUM>-conformant Media Access Control (MAC) and Physical Layer (PHY) interface to the Wireless Medium (WM). The network node <NUM> is however not limited to the above mentioned communication devices.

<FIG> shows a corresponding method <NUM> which may be executed in a receiving device <NUM>, such as the one shown in <FIG>. The method <NUM> comprises receiving <NUM> a control signal Sc associated with a transmitting device <NUM>. The control signal Sc comprises at least a first set of modulation symbols M1 mapped onto a set of frequency resources R within a first sub-band, and a second set of modulation symbols M2 mapped onto a corresponding set of frequency resources R' within a second sub-band. The first set of mapped modulation symbols M1' and the second set of mapped modulation symbols M2' differ from each other in at least one modulation symbol and are associated with control information. The method <NUM> further comprises deriving <NUM> the control information based on the control signal Sc.

<FIG> shows signalling aspects of an implementation of the disclosure. The transmitter device/user device <NUM>/<NUM> receives an optional PUCCH allocation signal from the receiving device/network node <NUM>/<NUM>. The network node <NUM> allocates resources for the PUCCH, either dynamically or semi-statically and receives the PUCCH on the assigned resources. The user device <NUM> therefore transmits a control signal Sc to the network node in the uplink <NUM> in the PUCCH on the assigned PUCCH resources.

<FIG> also shows how the network node <NUM> transmits data to the user device <NUM> which determines uplink control information based on the received data from the network node <NUM>. The data sent by the network node <NUM> may relate to HARQ-ACK feedback, e.g. HARQ-ACK bits in response to data sent in the downlink from the eNodeB to the UE in the LTE context. Moreover, there are different types of uplink control information sent from the UE to the eNodeB in the LTE context, e.g. scheduling request which is a bit the UE sends to the eNodeB when it wants to be scheduled in the uplink; and channel state information which is measurements the UE does regarding the channel properties (e.g., channel quality, transmission rank, precoder matrix, etc.) which the UE sends back to the eNodeB.

<FIG> shows a corresponding wireless communication system <NUM> comprising at least one transmitting device/user device <NUM>/<NUM> and at least one receiving device/network node <NUM>/<NUM> according to implementations of the disclosure. The user device <NUM> transmits a control signal Sc to a network node <NUM> in the uplink <NUM>. The control signal is a control signal Sc as described previously.

In this disclosure the expressions "set" and "cluster" can be used interchangeably. A set or cluster of frequency resources refers to one or several frequency contiguous resources, e.g., one or several REs/PRBs, and clusters may or may not be consecutively located. The clusters are non-overlapping, i.e., they have no resources in common. Further, most of the following examples and implementations are described in a 3GPP LTE or LTE Advanced context with its relevant terminology and expressions. Implementations of the disclosure are however not limited thereof and may be used in any suitable wireless communication system.

A general multi-cluster PUCCH signal generation block diagram is shown in <FIG>, where not all the blocks/steps are needed for a specific PUCCH format. The functional blocks/steps in <FIG> may be comprised/executed in the present signal processor <NUM> of the transmitting device <NUM>. It is noted that the corresponding steps, such as decoding, descrambling, demodulation, demapping, etc., are performed in the receiving device <NUM>.

The encoding block <NUM> may comprise different channel coding schemes, e.g., block code or tail biting convolutional coding, with or without CRC (Cyclic Redundancy Check) attachment.

The bit level processing block <NUM> may comprise scrambling and interleaving.

The modulation mapper block <NUM> takes as input the bits, which are mapped to modulation symbols ,e.g., BPSK (Binary Phase Shift Keying) or QPSK (Quartenary PSK) symbols. The modulation mapper may perform the mapping e.g., according to Gray mapping. The modulation mapper can further produce modulation symbols which are obtained from sequences. For example, bits can be mapped to sequences or products of different sequences, where typical sequences include Zadoff-Chu sequences and Orthogonal Cover Codes (e.g., Hadamard sequences, cyclically shifted exponential sequences).

The symbol level processing block <NUM> may comprise cyclic shifts, interleaving, sequence modulation and spreading.

The multi-cluster mapper block <NUM> maps modulated symbols to sets/clusters, uniformly spaced in the frequency domain. In one implementation of multi-cluster mapper <NUM>, each cluster comprises <MAT> REs, i.e., <NUM> REs per PRB, where <MAT> is the PUCCH bandwidth in PRBs (of the corresponding PUCCH format defined in LTE), which is <NUM> for PUCCH format <NUM>/<NUM> and potentially larger than <NUM> for PUCCH format <NUM>. An illustration of multi-cluster PUCCH with <NUM> clusters, each cluster consisting of <NUM> PRB for a <NUM> PRB carrier bandwidth, is shown in <FIG>. Here, the bandwidth is divided into <NUM> sub-bands, each comprising <NUM> RBs. The set R and R' include the second RB in the respective sub-band. The actual PUCCH transmission will thus occupy <NUM> PRBs located uniformly over <NUM> PRBs. The principles herein could be generalized even for other number of clusters.

In another example of multi-cluster mapper <NUM>, each cluster comprises <NUM> REs (i.e., <NUM> PRB) even when <MAT>. Thus, if <MAT> is not larger than the total number of allocated PRBs (e.g., <NUM>), modulation symbols are first mapped to <MAT> clusters and may be repeated in some of the remaining clusters. Alternatively, some of the remaining clusters could be left empty. This allows using less total number of RBs for a given bandwidth <MAT> than for the multi-cluster mapper defined above. Thus, the modulation symbols may become the same in some clusters while being different in some clusters. For example, if <MAT> and there are <NUM> clusters each consisting of <NUM> PRB pair, the modulation symbols are first mapped to cluster <NUM> to <NUM> and then repeated for the remaining clusters <NUM> to <NUM>. Thus different modulation symbols may be contained in cluster <NUM> to <NUM>. Then the same mapping is repeated and applied for cluster <NUM> to <NUM> (note: any other predetermined mapping with repetition may also be used). Thus the same modulation symbols are mapped to cluster <NUM> and <NUM>; <NUM> and <NUM>; <NUM> and <NUM>; <NUM> and <NUM>; <NUM> and <NUM>. The skilled reader may understand that similar mapping could be used even when the total number of clusters is not divisible by <MAT>. For which case either some clusters may be left empty or different clusters may be repeated different number of times.

The SC-FDMA waveform, generated in the SC-FDMA signal generator block <NUM> in <FIG>, is in LTE such that the time-continuous low-pass signal <MAT> for antenna port p in SC-FDMA symbol <NUM> in an uplink slot is defined by: <MAT> for <NUM> ≤ t < (NCP,l + N) × Ts where <MAT>. The variable N equals <NUM> for Δf = <NUM> subcarrier spacing and <MAT> is the content of resource element (k,<NUM>) on antenna port p. The entities Ts, NCP,l, <MAT> and <MAT> are further defined in the LTE specifications. The SC-FDMA waveform without a cyclic prefix can be defined by: <MAT> for <NUM> ≤ t < N × Ts. According to the LTE standard, <MAT>, hence it is possible to define: <MAT> and <MAT>.

The sampled version is obtained by setting: t = n/fs which gives (comprising a normalisation factor <MAT>), a low-pass equivalent signal: <MAT> for n = <NUM>,<NUM>,. , N - <NUM> where H[k] is a Fourier coefficient at frequency k.

The Fourier coefficients are obtained by DFT precoding in <NUM> the modulation symbols Xm as: <MAT>.

If the same Fourier coefficient is used in multiple clusters, it can be realized from the low-pass equivalent signal representation that the PAPR/CM of the signal may increase. As an illustrative example, if H[k] = H[k + Δ], then <MAT>, and for certain n, the factor <MAT>. Further generalizing H[k] = H[k + Δ · p], p = <NUM>,<NUM>,. , P - <NUM>, it can be found that <MAT>. It follows that for certain n, <MAT>. That is, repeating Fourier coefficients could result in constructive addition of subcarriers leading to large power dynamics of the signal. It is noted that the same conclusion holds without a DFT precoder, for which the Fourier coefficient becomes the same as the modulation symbol Xm. Hence, it is disclosed herein to avoid repetition of Fourier coefficients/modulation symbols in the SC-FDMA signal.

Accordingly, in an implementation of the disclosure, the signal processor <NUM> of the transmitting device <NUM> is configured to provide a first set of precoded modulation symbols M1 and a second set of precoded modulation symbols M2 by DFT precoding the first set of modulation symbols M1 and the second set of modulation symbols M2. The signal processor <NUM> of the transmitting device <NUM> is further configured to provide the first set of mapped modulation symbols M1' by mapping the first set of precoded modulation symbols M1 onto the set of frequency resources R within the first sub-band, and provide the second set of mapped modulation symbols M2' by mapping the second set of precoded modulation symbols M2 onto a corresponding set of frequency resources R' within a second sub-band.

In one implementation the following holds:.

By different modulation symbols/bits in different sub-bands, it should be understood that it includes that at least one modulation symbol/bit is different among the two sub-bands. In particular, if a DFT precoder is applied, the difference could be observed after the DFT precoder. That is the difference should be viewed on the sets of modulation symbols mapped to the time-frequency resources.

Hence, the signal processor <NUM> is configured to precode the first set of modulation symbols M1 using a first sub-band specific DFT precoder for the first sub-band and precode the second set of modulation symbols M2 using a second sub-band specific DFT precoder for the second sub-band.

One example of this implementation is provided in <FIG>. The UCI is provided by UCI providing block <NUM>. The modulated symbol set derived from the UCI can be done with the procedures comprising encoding, bit level processing, modulation mapping, symbol level processing and transform precoding in modulated symbol generation blocks <NUM> for modulated symbol sets <NUM>, <NUM>,. , N (wherein N is a positive integer). In the present implementation, the transform precoding is also named as DFT precoding. The post DFT precoder symbols are mapped to multi-clusters in multi-cluster mapper block <NUM> and then processed with SC-FDMA signal generation in signal generation block <NUM>. The signal generation is performed in the transmitting device <NUM>. Corresponding steps, e.g., decoding, descrambling, demodulation, demapping, etc. are performed in the receiving device <NUM>.

This implementation is advantageous because:.

The generation of the different modulated symbol sets corresponding to the same UCI can be done by cluster specific processing either at bit level or symbol level. For the bit level processing, one way is to perform cluster specific scrambling. For the symbol processing, one way is to perform cluster specific cyclic modulation symbol shifting. Cluster specific should in this disclosure be understood to include sub-band specific or PRB-specific processing.

One example of generating multi-cluster PUCCH, by scrambling, is:.

Therefore, the signal processor <NUM> is configured to scramble the bits representing the control information using a first sub-band specific scrambling sequence for the first sub-band and a second sub-band specific scrambling sequence for the second sub-band so as to provide a first scrambled sequence and a second scrambled sequence. The signal processor <NUM> is configured to modulate the first scrambled sequence and the second scrambled sequence so as to provide the first set of modulation symbols M1 and the second set of modulation symbols M2.

The different modulated symbol sets derived from the following: the block of bits b(<NUM>),. ,b(Mbit-<NUM>) shall be scrambled with a cluster (sub-band) specific scrambling sequence, resulting in a block of scrambled bits b̃(<NUM>),. ,b̃(Mbit -<NUM>). This could be done by b̃(i) = (b(i)+c(i))mod2, where the scrambling sequence c(i) is a sequence defined in 3GPP TS <NUM> clause <NUM>.

The pseudo-random scrambling sequence generator can utilize cluster or sub-band specific parameters, e.g., it can be initialized with <MAT> at the start of each subframe where nRNTI is the Cell-Radio Network Temporary Identifier (C-RNTI), ns is the slot number within a radio frame, <MAT> is the cell identity, and <MAT> is a cluster parameter (e.g., a PRB index, or a cluster index).

An advantage of scrambling is that it has low-complexity as it does not require any multiplications. It also requires minimum change to existing PUCCH formats and therefore reduces the cost and implementation complexity of the transmitter and receiver.

One example of generating multi-cluster PUCCH is to cyclically shift the order of the modulation symbols. The symbol level processing could apply a cluster specific modulation symbol shift or interleaver, e.g., <MAT>, where d(i) is the cluster-specific modulation symbol sequence, d̃(i) is the cluster-specific modulation symbol sequence after cyclic shifts, <MAT> is given by 3GPP TS <NUM> clause <NUM>, ns is the slot number within a radio frame and l is the SC-FDMA symbol number within a slot. An interleaver provides more randomization than a cyclic shift since it is not constrained to change the order by cyclic shifts only.

Therefore, the signal processor <NUM> is configured to interleave the first set of modulation symbols M1 using a first sub-band specific interleaver for the first sub-band and interleave the second set of modulation symbols M2 using a second sub-band specific interleaver for the second sub-band. Thereby, the first set of modulation symbols M1 and the second set of modulation symbols M2 are provided.

Therefore, the signal processor <NUM> is configured to cyclically shift the positions of the modulation symbols in the first set of modulation symbols M1 so as to provide the second set of modulation symbols M2, or cyclically shift the positions of the modulation symbols in the second set of modulation symbols (M2) so as to provide the first set of modulation symbols M1.

An advantage of cyclic shifting is that it has low-complexity as it does not require any multiplications. It also requires minimum change to existing PUCCH formats and therefore reduces the cost and implementation complexity of the transmitter and receiver.

One example of generating multi-cluster PUCCH is to multiply the modulation symbols in a cluster with a sub-band specific value being a complex or real value, and using different such values for different clusters. The complex or real values could be taken from a pre-defined sequence having a length equal to the number of clusters according to an implementation.

Therefore, the signal processor <NUM> is configured to multiply the first set of modulation symbols M1 using a first sub-band specific complex or real value for the first sub-band and multiply the second set of modulation symbols M2 using a second sub-band specific complex or real value for the second sub-band. Thereby, the first set of modulation symbols M1 and the second set of modulation symbols M2 are provided.

The symbol level processing could apply a cluster specific modulation symbol multiplication, e.g., <MAT>, where d(i) is the cluster-specific modulation symbol sequence, s(i) is the cluster-specific sequence (i.e., s(i) assumes the same value for all modulation symbols within a cluster), <MAT> is given by 3GPP TS <NUM> clause <NUM>, ns is the slot number within a radio frame and l is the SC-FDMA symbol number within a slot.

Examples of sequences s(i) could be such that only infer phase shifts of the modulation symbols (e.g., BPSK and QPSK-based sequences) or other sequences with desirable PAPR/CM properties, such as Zadoff-Chu sequences or Golay sequences.

The cubic metric performance is evaluated assuming multiple cluster structure, with different post-DFT modulated symbol sets and same post-DFT modulated symbol sets. The cubic metric is defined as: <MAT> where <MAT> is the raw cubic metric of the Wideband Code Division Multiple Access (W-CDMA) voice reference signal, and K is <NUM>.

There are <NUM> clusters with multiple different post-DFT modulated symbol sets each mapped to one cluster, and multiple same post-DFT modulated symbol sets each mapped to one cluster. The transmission bandwidth is <NUM> PRB and each cluster is <NUM> PRB. The symbols are QPSK modulated. It can be observed in Table <NUM> below that significant CM reduction can be achieved by using scrambling or cyclic shifting.

By performing the cluster specific operation into the generation of the multiple different post-DFT modulated symbol sets, different modulated symbols are mapped to different clusters before SC-FDMA signal generation, which achieves significant CM performance reduction over mapping the same modulated symbol set to different clusters.

According to the invention claimed in the present application, the following holds:.

Hence, the first set of modulation symbols M1 and the second set of modulation symbols M2 are identical in this implementation. Further, the signal processor <NUM> is configured to precode the first set of modulation symbols M1 and the second set of modulation symbols M2 using a single DFT precoder for the first sub-band and the second sub-band.

One example of this implementation with a single DFT precoder for all sub-bands is provided in <FIG>. Only one set of modulated symbols is derived from the UCI which is provided by UCI provider block <NUM>. The modulated symbol set derived from the UCI can be done with the procedures comprising encoding, bit level processing, modulation mapping and symbol level processing by modulated symbol generation block <NUM>. The modulated symbols are repeated by several times in repetition block <NUM>, and then processed with the single DFT precoder in transform precoder block <NUM>. The post DFT precoder symbols are mapped to multi-clusters in multi-cluster block <NUM> and then processed to produce the SC-FDMA signal in signal generation block <NUM>. The signal generation is performed in the transmitting device <NUM>. Corresponding blocks/steps, e.g., decoding, descrambling, demodulation, demapping, etc. are performed in the receiving device <NUM>.

One example of generating multi-cluster PUCCH based on a PUCCH format defined for <MAT> is:.

An advantage of using a single DFT precoder for all clusters is that the CM/PAPR can be made very low.

By applying a single DFT precoder for multiple repeated modulated symbol sets, different modulated symbols are derived and mapped to different clusters before SC-FDMA signal generation, which achieves significant CM performance reduction over mapping the same modulated symbol set to different clusters. Table <NUM> below shows that, for the same example as above, the cubic metric can be reduced to low levels.

It can be noted that due to the repetition of the modulation symbols, the computation of the DFT can decreased, as can be seen from the following example. Let X = [X<NUM>, X<NUM>,. , XM-<NUM>, X<NUM>, X<NUM>,. , XM-<NUM>,. , X<NUM>, X<NUM>,. , XM-<NUM>] be a vector of length N, containing N/M repetitions, such that Xk = Xk+Mp for an integer <MAT>. For n = <NUM>, <NUM>,. , N - <NUM>, <MAT> <MAT>.

Hence, the complexity of the N-point DFT is similar to an M-point DFT.

Furthermore, any methods according to implementations of the disclosure may be implemented in a computer program, having code means, which when run by processing means causes the processing means to execute the steps of the method. The computer readable medium may comprises of essentially any memory, such as a ROM (Read-Only Memory), a PROM (Programmable Read-Only Memory), an EPROM (Erasable PROM), a Flash memory, an EEPROM (Electrically Erasable PROM), or a hard disk drive.

Moreover, it is realized by the skilled person that the user device <NUM> and network node <NUM> comprise the necessary communication capabilities in the form of e.g., functions, means, units, elements, etc., for performing the present solution. Examples of other such means, units, elements and functions are: processors, memory, buffers, control logic, encoders, decoders, rate matchers, de-rate matchers, mapping units, multipliers, decision units, selecting units, switches, interleavers, de-interleavers, modulators, demodulators, inputs, outputs, antennas, amplifiers, receiver units, transmitter units, DSPs, MSDs, TCM encoder, TCM decoder, power supply units, power feeders, communication interfaces, communication protocols, etc. which are suitably arranged together for performing the present solution.

Especially, the signal processors may comprise, e.g., one or more instances of a Central Processing Unit (CPU), a processing unit, a processing circuit, a processor, an Application Specific Integrated Circuit (ASIC), a microprocessor, or other processing logic that may interpret and execute instructions. The expression "processor" may thus represent a processing circuitry comprising a plurality of processing circuits, such as, e.g., any, some or all of the ones mentioned above. The processing circuitry may further perform data processing functions for inputting, outputting, and processing of data comprising data buffering and device control functions, such as call processing control, user interface control, or the like.

Claim 1:
Transmitting device for transmitting uplink control information, UCI, on a physical uplink control channel, PUCCH, operable in a wireless communication system (<NUM>), the transmitting device (<NUM>) comprising
a signal processor (<NUM>) configured to
modulate bits representing uplink control information, UCI, for generating an initial set of modulation symbols and repeat the initial set of modulation symbols one or more times to separately generate multiple modulation symbol sets, wherein the multiple modulation symbol sets include at least a first set of modulation symbols, M1, and a second set of modulation symbols, M2;
precode, by using Discrete Fourier Transform, DFT, the first set of modulation symbols, M1, and the second set of modulation symbols, M2;
provide a first set of mapped modulation symbols, M1', by mapping the first set of modulation symbols, M1, onto a set of frequency resources, R, within a first sub-band, and
provide a second set of mapped modulation symbols, M2', by mapping the second set of modulation symbols, M2, onto a corresponding set of frequency resources, R', within a second sub-band,
wherein the first set of mapped modulation symbols, M1', and the second set of mapped modulation symbols, M2', occupy a same slot in a subframe; and wherein the first sub-band and the second sub-band are non-overlapping; and
wherein the first set of mapped modulation symbols, M1', and the second set of mapped modulation symbols, M2', differ from each other in at least one modulation symbol;
wherein the signal processor (<NUM>) is configured to
precode the first set of modulation symbols, M1, and the second set of modulation symbols, M2, using a single DFT precoder for the first sub-band and the second sub-band.