Mechanism for time-domain transmission of sounding reference signals
By distributing SRS resources in the time domain and generating flexible transmission sequences based on channel parameters, the method addresses the limitations of orthogonal frequency allocation, enhancing channel estimation and reducing interference in SRS transmission.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- HUAWEI TECH CO LTD
- Filing Date
- 2024-12-23
- Publication Date
- 2026-07-02
AI Technical Summary
Existing SRS transmission methods in 3GPP require orthogonal resource allocation across the whole frequency band for each UE and antenna port, leading to increased periodicity and outdated channel information, resulting in sub-optimal decisions by the gNB.
A method and system for multiplexing SRS signals by distributing resources in the time domain, allowing for irregular patterns in the frequency domain across ports and UEs, using configuration information to generate scheduled transmission sequences based on channel parameters and updating these sequences dynamically.
Enables flexible and efficient resource allocation, reducing interference and improving channel estimation accuracy by allowing arbitrary patterns in the frequency domain while maintaining compatibility with current 3GPP frameworks.
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Figure CN2024141477_02072026_PF_FP_ABST
Abstract
Description
MECHANISM FOR TIME-DOMAIN TRANSMISSION OF SOUNDING REFERENCE SIGNALSTECHNICAL FIELD
[0001] The present disclosure relates to a method that enables CDM across user equipment and ports when sound reference signal pattern is irregular in frequency domain.BACKGROUND
[0002] SRS are broadband pilots sent in the uplink (UL) by the user equipment (UE) . They are essential for the gNB to estimate the channel to perform downlink precoding and scheduling. The main issue with SRS is that each UE needs to be allocated orthogonal resources across the whole frequency band and for each antenna port for the transmission of SRS, which leads to a rapid increase on the periodicity of SRS, i.e., the time between two consecutive SRS transmissions for the same UE. If the periodicity is very large, gNB has out-of-date information about the channel, leading to sub-optimal decisions.
[0003] The present disclosure is therefore aimed towards providing methods and systems for solving at least the afore-mentioned problems.SUMMARY
[0004] According to the present disclosure there is provided a method for performing multiplexing of signals in a network, where the method comprises: sending configuration information from one or more node to one or more user resource; providing, to the one or more resource, a set of one or more carriers over which to transmit one or more signal; generating a scheduled transmission sequence for signal transmission in a time domain based on the configuration information and the set of one or more carrier frequency; transmitting the one or more signal from the one or more resource to the one or more node in dependence on the scheduled transmission sequence; estimating, at the one or more node, one or more channel parameter of the one or more resource in dependence on the transmitted signals; and updating the configuration information based on the one or more estimated channel parameters. This allows the assignment of arbitrary and irregular pattern in the frequency domain across ports and UEs while avoiding collisions of the sequences.
[0005] The method described above, wherein the one or more node is one or more gNodeB and the one or more resource is one or more user equipment. This allows for the specific node and resource types to be used as part of the method and system.
[0006] The method described above, wherein updating the configuration information comprises one or more of: transmitting, by the one or more node, updated configuration information as downlink control information of a physical downlink control channel; transmitting, by the one or more node, updated configuration information in non-real time by a radio resource control protocol; and transmitting, by the one or more node, updated configuration information using one or more predetermined configuration information index tables. This provides alternate means of updating the configuration and allows for the updating to be undertaken by different parts of the system.
[0007] The method described above, wherein the configuration information comprises: a port combination index representing the number of ports to be used for transmission; a carrier frequency index; a sequence length comprising a time-domain comb value; and a time-domain offset based on the port combination index. This allows for the system to be configured using the appropriate values and provides the ability of a user to customise the setup.
[0008] The method described above, wherein the method further comprises: generating one or more index tables of configuration information according to current conditions of the network; and storing at both the one or more node and the one or more resource the generated one or more index tables. This allows for preconfigured tables to be used to configure the system and only the most relevant system configurations to be stored.
[0009] The method described above, wherein the one or more signal is one or more sound reference signal. This provides a specific type of signal to be transmitted.
[0010] The method as described above, wherein generating a scheduled transmission sequence for signal transmission comprises: calculating a transmission sequence for each port in dependence on a time-domain comb which represents a sequence in time at which to allocate resources for transmission as the one or more signal. This allows different transmission sequences to be calculated for different ports and different resources.
[0011] There is also provided a system for performing multiplexing of signals in a network, the system comprising one or more node and one or more resource and where the one or more node and one or more resource comprise one or more processors configured to: send configuration information from one or more node to one or more user resource; provide, to the one or more resource, a set of one or more carriers over which to transmit one or more signal; generate a scheduled transmission sequence for signal transmission in a time domain based on the configuration information and the set of one or more carrier frequency; transmit the one or more signal from the one or more resource to the one or more node in dependence on the scheduled transmission sequence; estimate, at the one or more node, one or more channel parameter of the one or more resource in dependence on the transmitted signals; and update the configuration information based on the one or more estimated channel parameters. This allows different sub-carrier selection across ports and UEs can be achieved because the SRS sequences are spread in the time domain and transmitted.
[0012] The system described above, wherein the one or more node is one or more gNodeB and the one or more resource is one or more user equipment. This allows for the specific node and resource types to be used as part of the method and system.
[0013] The system described above, wherein one or more processor is configured, in updating the configuration information, to: transmit, using the one or more node, updated configuration information as downlink control information of a physical downlink control channel; transmit, using the one or more node, updated configuration information in non-real time by a radio resource control protocol; and transmit, using the one or more node, updated configuration information using one or more predetermined configuration information index tables. This provides alternate means of updating the configuration and allows for the updating to be undertaken by different parts of the system.
[0014] The system described above, wherein the configuration information comprises: a port combination index representing the number of ports to be used for transmission; a carrier frequency index; a sequence length comprising a time-domain comb value; and a time-domain offset based on the port combination index. This allows for the system to be configured using the appropriate values and provides the ability of a user to customise the setup.
[0015] The system described above, wherein the system is further configured to: generate one or more index tables of configuration information according to current conditions of the network; and store at both the one or more node and the one or more resource the generated one or more index tables. This allows for preconfigured tables to be used to configure the system and only the most relevant system configurations to be stored.
[0016] The system described above, wherein the one or more signal is one or more sound reference signal. This provides a specific type of signal to be transmitted.
[0017] The system described above, wherein the system is configured, in generating a scheduled transmission sequence for signal transmission, to: calculate a transmission sequence for each port in dependence on a time-domain comb which represents a sequence in time at which to allocate resources for transmission as the one or more signal. This allows different transmission sequences to be calculated for different ports and different resources.
[0018] There is also provided a computer program stored in stored in non-transitory form comprising a program code for performing the method described above when executed on a computer. This allows different sub-carrier selection across ports and UEs can be achieved because the SRS sequences are spread in the time domain and transmitted. This further allows the method to be implemented on a computer.BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The present disclosure is described by way of example, with reference to the accompanying drawings, in which:
[0020] Figure 1 illustrates an example description of parameters defining the mapping of an SRS sequence to the physical resources;
[0021] Figure 2 illustrates an example of SRS allocation with comb 2;
[0022] Figure 3 illustrates an example of allocation of SRS sequences in time domain with comb 2;
[0023] Figure 4 illustrates an example of a procedure between a gNB and a UE for time-domain SRS transmission.DETAILED DESCRIPTION
[0024] The present disclosure is primarily concerned with the expansion of an SRS framework using during multiplexing of said signals within a network.
[0025] An SRS framework is specified in 3GPP TS 38.211, clause 6.4.1.4. In relation to the present disclosure, it is relevant to know that each UE is assigned a certain amount of resources in time and frequency. To control the number of resources in time domain, the gNodeB (gNB) may communicate the parameter nofSymbols to the UE as a field in the RRC message SRS-ResourceConfig (TS 38.331, clause 6.2.3) . For the resources in frequency domain, the gNB may specify the transmissionComb parameter related to the comb, which represents the density of pilots in frequency for the UE, e.g., a transmissionComb of 2 means that the UE transmits one SRS pilot in every second resource elements (RE) , in other words every other resource element. A transmissionComb of 4 means that one SRS pilot signal is transmitted every fourth resource element, or comb of 8 in every 8th resource element. In this way, the gNB can multiplex multiple user equipment devices in the same frequency band by assigning the same transmissionComb with a different frequency shift, i.e., the starting frequency index. Additionally, in order to separate different ports allocated to the same time-frequency resources, Code Division Multiplex (CDM) based on cyclic-shifted Zadoff-Chu (ZC) sequences may be used. It should be noted that the sequences of resource allocation are currently only spread in the frequency domain. The use of several time-domain symbols in the equation shown in Figure 1 allows for the transmission of several sequences for the same ports close to each other to improve estimation accuracy. The example sequence calculation shown in Figure 1 does not at present provide a means for spreading the SRS in the time domain.
[0026] Figure 2 illustrates an example of how an SRS sequence r for port pi is mapped to the frequency-time resources. Figure 2 shows the mapping for N ports using transmissionComb of 2, in which the signals are allocated to every other resource for each port for each of the N ports. The different patterned allocated resources shown in Figure 2 represent the different sequences of resources for each port. Figure 2 provides an example, in which the resources are allocated in frequency spread manner. It should be noted that in the example of Figures 1 and 2, regardless of the value of the parameters, the SRS pilots are always mapped with a regular pattern in the frequency domain. The disadvantage of this approach currently used in 3GPP, while SRS pilots are spread regularly in the frequency domain, some mechanisms may create irregular allocation of pilots in the frequency domain for different UEs and / or ports of a UE. This may lead to a loss of orthogonality, which results in interference across ports and limiting the potential of the network.
[0027] The present disclosure is intended to address these issues posed by frequency allocation of resources by distributing resources for allocation in the time domain. This is achieved by a new method that enables CDM across UEs and ports when SRS pattern is irregular in frequency domain. This disclosure therefore provides spreading the root sequence in the time domain instead of in the frequency domain, and defines a new sequence per port depending on number of ports to be multiplexed, a time-domain Comb, a time-domain Comb offset, and sequence length. Figure 3 shows the mapping of the frequencies in time domain.
[0028] An example of time domain spreading of resources can be seen illustrated in Figure 3. In the example of Figure 3 of this disclosure, it is assumed that the user equipment knows the sub-carriers (SC) on which to transmit SRS pilots (signals) . In the examples of this disclosure a carrier frequency may be considered to be a sub-carrier frequency and the term sub-carrier may be used to describe the carrier frequency. This information can be directly determined by the user equipment or shared by the gNodeB to the user equipment. For the purpose of this disclosure what is relevant is how the sequences or resources can be spread (allocated) in the time domain using an improved mechanism and improved procedures than those currently utilised by current SRS framework in 3GPP. It is therefore a desire of this disclosure to enable flexible selection and mapping of the resource sequences according to network and channel conditions. For example, if the UEs have high mobility, the resource sequences should be short and use consecutive Orthogonal Frequency-Division Multiplexing (OFDM) symbols, so that the duration of the sequence is as short as possible. This will assist in avoiding high channel fluctuations during sequence transmission. Alternatively, if the channels are fairly stable in time, it is preferable to spread the resource sequence with as much spacing as possible between consecutive SRS samples to allow the multiplexing of as many UEs as possible on the same amount of time resources. The system and method of this disclosure enable these types of decisions to be provided by the gNB with a flexible framework while maintaining as much compatibility as possible with the current 3GPP framework.
[0029] As can be seen in Figure 3, the resource sequences for each of the ports 1 to N are allocated across the time domain such that the resource sequences can be multiplexed. In a similar way to Figure 2, Figure 3 illustrates a comb of 2 but instead of a frequency domain comb of 2, Figure 3 illustrates a time domain comb of 2. In other words, the resources are allocated in every other time slot (1 in 2 time slots) .
[0030] All the embodiments of this disclosure take into consideration the 5G Radio Access Network (RAN) architecture defined by 3GPP as documented in TS 38.211 and TS 38.331. Specifically, the embodiments are focused on the extensions / modifications related to the RRC protocol for SRS configuration (TS 38.331) and DCI configuration (TS 38.214) , and the generation of SRS (TS 38.211) . The method and configuration of the system of this disclosure will now be described in relation to Figure 4. Figure 4 illustrates an example procedure between a gNodeB and user equipment for time-domain SRS transmission. The method proceeds generally by sending configuration information from one or more node to one or more user resource; providing, to the one or more resource, a set of one or more carriers over which to transmit one or more signal. The method then includes the generation of a scheduled transmission sequence for signal transmission in a time domain based on the configuration information and the set of one or more carrier frequency. The method may further comprise transmitting the one or more signal from the one or more resource to the one or more node in dependence on the scheduled transmission sequence; estimating, at the one or more node, one or more channel parameter of the one or more resource in dependence on the transmitted signals; and updating the configuration information based on the one or more estimated channel parameters.
[0031] In detail in relation to Figure 4, the method may comprise providing communication parameters in one or more methods. The communication parameters should be considered configuration information. The communication parameters may be provided by the gNB that sends a RRC-SRS-ResourceConfig message to UE. This message may comprise configuration information that includes a time-domain Comb LTC, a time-domain Comb offset l0, a sequence length M per port combination index Np, and a cinit per Np. Alternatively, the gNB may send an index s which is a table index that may contain one or more of the parameters above and listed in Figure 4. In a further alternative, the user equipment (which should be understood to be a user resource as described above) may determine a set of sub-carriers {k}to transmit SRS pilots (signals) on, or the set of sub-carriers may be provided by the gNB. All of these examples may be considered to be providing, to the one or more resource, a set of one or more carriers over which to transmit one or more signal. In these ways the parameters for PHY mapping per sub-carrier k can be determined. These options can be further described as follows.
[0032] There are two example options described above that may be employed in the method and system of the present disclosure. These are: i) Communicate parameters in RRC, or ii) communicate an index of a pre-defined table indicating the combination of parameters. For the first option, gNB sends SRS-ResourceConfig message to UE including port combination index Np, time-domain Comb LTC, time-domain Comb offset l0, sequence length M per port combination index Np, and cinit per Np. For the second option, one can define several tables such as Tables 2 and 3 both at gNB and UE containing some relevant combinations of Np, ports, M, l0 and LTC. The gNB then indicates with an index s in SRS-ResourceConfig indicating the table to use for parameters mapping. In some cases, the method may comprise generating one or more index tables of configuration information according to current conditions of the network; and storing at both the one or more node and the one or more resource the generated one or more index tables. It will be note that Table 2 illustrates a first example of pre-stored tables with relevant combination of parameters according to network conditions, and Table 3 illustrates a second example of pre-stored tables with relevant combination of parameters according to network conditions.
[0033] Table 2
[0034] Table 3
[0035] The method shown in Figure 4 then comprises generating a scheduled transmission sequence (asequence in Figure 4) for signal transmission in a time domain based on the configuration information and the set of one or more carrier frequency. The sequences may be generated in a number of ways however, one example of the sequence generation will now be described. It should be noted that this is not the only method of sequence generation and is provided as an example only. In some examples generating a scheduled transmission sequence for signal transmission comprises: calculating a transmission sequence for each port in dependence on a time-domain comb which represents a sequence in time at which to allocate resources for transmission as the one or more signal.
[0036] The SRS sequences can be generated using Zadoff-Chu sequences as indicated in TS 38.211 Clause 6.4.1.4.2. Alternatively, Gold sequences can be used as indicated in in TS 38.211 Clause 5.2.1. Alternatively, the SRS sequences can be generated using the columns of a DFT matrix. As an example, consider the DFT matrix F of dimensions The SRS sequence given by related to its value for port pi, OFDM symbol l′ and entry can be generated according to the expression,
[0037] where ri (n) is the n-th element of the i-th column of the DFT matrix F given by:
[0038] Using these example expressions the signalling sequences can be generated by the user resources and these can then be mapped to physical resources using the following example expressions.
[0039] The root sequence r for antenna port pi and port combination Np may be mapped to carrier frequency resources following the following formula:
[0040] In this example expression it can be assumed that the sub-carrier (SC) k is given by the particular allocation strategy. The sequence length M can be selected according to e. g. UEs coherent time. The parameters of the above formula are described in Table 1. Table 1 illustrates an example of the configuration information parameters.
[0041] Table 1
[0042] The method of Figure 4 that may be implemented by the system of this disclosure may further comprise the step of transmitting the one or more signal from the one or more resource to the one or more node in dependence on the scheduled transmission sequence. This is shown in step 3 of Figure 4. Once the signals have been transmitted between the user resource and the one or more node (gNB) , then the method may comprise estimating, at the one or more node, one or more channel parameter of the one or more user resource in dependence on the transmitted signals. The one or more channel and network parameter may be considered to be one or more of coherent time, channel covariance matrix, delay spread, Doppler spread, SNR, SINR, RSRP, RSRQ, number of ports, number of UEs. One or more of these parameters may be used when determining the configuration of the system and user equipment. In the example of Figure 4, the one or more channel parameter is coherent time. The method may then include the step 5 in which the parameters used to configure the system may be selected according to the now known conditions of the system that may be identified based on the transmission of the signals between the gNB and the user resource.
[0043] The method may then comprise updating the configuration information based on the one or more estimated channel parameters as shown in Steps 5 and 6 of Figure 4. This may be achieved in a number of ways. In one example the user resource (UE) may determine sequence according to provided values from gNB. Alternatively, the user resource may be configured to transmit signals (SRS) with sequences to the one or more node of the system. A further option for updating the configuration information is that the one or more node (gNB) may be configured to estimate new parameters according to channel parameters of UE.
[0044] Once the method and system have updated the configuration this new configuration should be transmitted to the constituent members of the system. The method may therefore comprise communicating the updated configuration information to the user resources. This may achieved as part of the updating step where updating the configuration information comprises one or more of: transmitting, by the one or more node, updated configuration information as downlink control information of a physical downlink control channel; transmitting, by the one or more node, updated configuration information in non-real time by a radio resource control protocol; and transmitting, by the one or more node, updated configuration information using one or more predetermined configuration information index tables. In other words, the method may include one or more of the gNB communicating the new set of parameters in DCI of the PDCCH; the gNB communicating the new set of parameters by sending a reconfiguration command for RRC with the updated value in SRS-ResourceConfig; or the gNB communicating the new set of parameters by communicating new SRS resource in DCI of the PDCCH. The user resource may need to be preconfigured with the corresponding set of parameters at the UE. In some cases, the configuration information comprises: a port combination index representing the number of ports to be used for transmission; a carrier frequency index; a sequence length comprising a time-domain comb value; and a time-domain offset based on the port combination index.
[0045] The above disclosure provides a method for spreading signals across resources in the time domain in an SRS communication network. To provide an indication of the time-domain the gNB can indicate the UE that the SRS are transmitted in the time domain buy including a parameter in SRSConfig Information Element (IE) .
[0046] One example to encode this information into the SRS-Config IE using ASN. 1 encoding is as follows:
[0047] Note that SRSDomain is included in the SRS-ResourceSet IE, is optional, and, if included, it requires reconfiguration. SRS-ResourceSet is included in the SRS-Config IE according to TS 38.331 Clause 6.2.3.
[0048] The present disclosure also provides a system for performing multiplexing of signals in a network, the system comprising one or more node and one or more resource and where the one or more node and one or more resource comprise one or more processors. The one or more processors may be configured to perform the method described above and more specifically may be configured to send configuration information from one or more node to one or more user resource; provide, to the one or more resource, a set of one or more carriers over which to transmit one or more signal; generate a scheduled transmission sequence for signal transmission in a time domain based on the configuration information and the set of one or more carrier frequency. The one or more processors may further be configured to transmit the one or more signal from the one or more resource to the one or more node in dependence on the scheduled transmission sequence; estimate, at the one or more node, one or more channel parameter of the one or more resource in dependence on the transmitted signals; and update the configuration information based on the one or more estimated channel parameters. In this way, the system can provide the means for performing the method above and may be formed of a gNB that has the capacity to receive SRS signals spread in the time domain from multiple ports and UEs on the same physical resources. There is also provided a computer program stored in stored in non-transitory form comprising a program code for performing the method as described above when executed on a computer.
[0049] It will be clear that the gNB of this disclosure that may form all or part of the system disclosed herein may be identified in the following ways. If the gNB is being sold by a Mobile Network Vendor, from analysis of the product manual, where a list of the interfaces and capabilities need to be listed it will be possible to verify the type of SRS transmission offered by such product, and if it mentions any of the parameters covered in this disclosure. If the gNB is being sold by a Mobile Network Integration company, the offer of customization, if such offer covers the implementation of specific parts of the 3GPP standard related to the support for the transmission SRS pilots in the time domain (assuming that the solution has been included in the standard) could be detected. This means that such company would be customizing a gNB with definitions of 3GPP that are covered by this disclosure. If the vendor of the gNB does not make available any Application Programming Interface (API) of Product / Software, or in the case of a UE, it is still possible to intercept the traffic “in and out” of the gNB / UE and look for the following fields in the captured packets that include for the gNB: if SRS-ResourceConfig message sent with the Radio Resource Control (RRC) contains any of the fields presented in the previous section, the gNB can support the transmission SRS pilots in the time domain. For the UE:if the UE transmits SRS pilots in the time domain after configuration from the gNB.
[0050] The system and method of this disclosure therefore provide a number of advantages over the present methods of frequency spread resource allocation. These are that it is possible to determine parameters for PHY mapping per sub-carrier k by defining new formula for sequence and by exchanging the new parameters the UE knows how to calculate the SRS sequence spread on the time domain. It is also possible to update parameters according to UE channel parameters by transmitting the SRS sequences spread in the time domain, different sub-carrier selection across ports and UEs can be achieved. Finally, it is possible to update parameters to the user resources by selecting parameters based on UE coherent time, good trade-offs between port interference and estimation error can be achieved.
[0051] To aid the understanding of the reader there are provided the following explanations of terms used in this disclosure.
[0052] Pilot signals: Known signals both to transmitter and receiver used in modern communication systems to perform channel estimation, Multiple-Input Multiple-Output (MIMO) precoding, Adaptive Modulation and Coding (AMC) , scheduling, beam-management, and other procedures related to adapting the transmission to the current channel conditions. These signals are typically “scrambled” with data signals in time and frequency domains so the channel conditions experienced by pilots and data are as identical as possible.
[0053] Sounding Reference Signals (SRS) : These are pilot signals used in Time Division Duplex (TDD) and sent by the UE to the gNB. SRS are typically allocated in frequency regions not currently used for uplink (UL) data transmission between a particular UE and gNB. This information, together with the assumption of channel reciprocity in TDD systems, allows the gNB to know the channel conditions in frequency bands outside of the current UL ones for one UE. With this information, the gNB can perform downlink (DL) precoding, scheduling, etc., without the need of explicit Channel State Information (CSI) feedback from the UE. The current framework for SRS transmission in 3GPP is described in the TS 38.211, Clause 6.4.1.4.
[0054] Sub-band: a frequency band from which a subset of sub-carriers (SCs) is selected. Candidate SCs: The set of SCs per sub-band from which the UE can select for SRS transmission. Transmit SCs: The subset of SCs out of the candidate SCs per sub-band on which the UE selects to transmit. Comb: periodicity of SRS pilots in the frequency domain, e. g. comb 2 indicates that the UE transmits SRS in every second SC.
Claims
1.A method for performing multiplexing of signals in a network, where the method comprises:sending configuration information from one or more node to one or more user resource;providing, to the one or more resource, a set of one or more carriers over which to transmit one or more signal;generating a scheduled transmission sequence for signal transmission in a time domain based on the configuration information and the set of one or more carrier frequency;transmitting the one or more signal from the one or more resource to the one or more node in dependence on the scheduled transmission sequence;estimating, at the one or more node, one or more channel parameter of the one or more resource in dependence on the transmitted signals; andupdating the configuration information based on the one or more estimated channel parameters.2.The method of claim 1, wherein the one or more node is one or more gNodeB and the one or more resource is one or more user equipment.3.The method of claim 1 or 2, wherein updating the configuration information comprises one or more of:transmitting, by the one or more node, updated configuration information as downlink control information of a physical downlink control channel;transmitting, by the one or more node, updated configuration information in non-real time by a radio resource control protocol; andtransmitting, by the one or more node, updated configuration information using one or more predetermined configuration information index tables.4.The method of any preceding claim, wherein the configuration information comprises:a port combination index representing the number of ports to be used for transmission;a carrier frequency index;a sequence length comprising a time-domain comb value; anda time-domain offset based on the port combination index.5.The method of any preceding claim, wherein the method further comprises:generating one or more index tables of configuration information according to current conditions of the network; andstoring at both the one or more node and the one or more resource the generated one or more index tables.6.The method according to any preceding claim, wherein the one or more signal is one or more sound reference signal.7.The method according to any preceding claim, wherein generating a scheduled transmission sequence for signal transmission comprises:calculating a transmission sequence for each port in dependence on a time-domain comb which represents a sequence in time at which to allocate resources for transmission as the one or more signal.8.A system for performing multiplexing of signals in a network, the system comprising one or more node and one or more resource and where the one or more node and one or more resource comprise one or more processors configured to:send configuration information from one or more node to one or more user resource;provide, to the one or more resource, a set of one or more carriers over which to transmit one or more signal;generate a scheduled transmission sequence for signal transmission in a time domain based on the configuration information and the set of one or more carrier frequency;transmit the one or more signal from the one or more resource to the one or more node in dependence on the scheduled transmission sequence;estimate, at the one or more node, one or more channel parameter of the one or more resource in dependence on the transmitted signals; andupdate the configuration information based on the one or more estimated channel parameters.9.The system of claim 8, wherein the one or more node is one or more gNodeB and the one or more resource is one or more user equipment.10.The system of claim 8 or 9, wherein one or more processor is configured, in updating the configuration information, to:transmit, using the one or more node, updated configuration information as downlink control information of a physical downlink control channel;transmit, using the one or more node, updated configuration information in non-real time by a radio resource control protocol; andtransmit, using the one or more node, updated configuration information using one or more predetermined configuration information index tables.11.The system of any one of claims 8 to 10, wherein the configuration information comprises:a port combination index representing the number of ports to be used for transmission;a carrier frequency index;a sequence length comprising a time-domain comb value; anda time-domain offset based on the port combination index.12.The system of any one of claims 8 to 11, wherein the system is further configured to:generate one or more index tables of configuration information according to current conditions of the network; andstore at both the one or more node and the one or more resource the generated one or more index tables.13.The system of any one of claims 8 to 12, wherein the one or more signal is one or more sound reference signal.14.The system of any one of claims 8 to 13, wherein the system is configured, in generating a scheduled transmission sequence for signal transmission, to:calculate a transmission sequence for each port in dependence on a time-domain comb which represents a sequence in time at which to allocate resources for transmission as the one or more signal.15.A computer program stored in stored in non-transitory form comprising a program code for performing the method according to any one of claims 1 to 7 when executed on a computer.