CN111869300B

CN111869300B - Physical downlink control channel candidate selection method and system

Info

Publication number: CN111869300B
Application number: CN201880091487.5A
Authority: CN
Inventors: 贺海港; 郝鹏; 左志松; 毕峰; 张晨晨
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2018-04-06
Filing date: 2018-04-06
Publication date: 2023-04-07
Anticipated expiration: 2038-04-06
Also published as: CN111869300A; EP3777417A1; EP3777417A4; WO2019192018A1

Abstract

Methods, systems, and devices for Physical Downlink Control Channel (PDCCH) candidate selection are disclosed. One example method includes performing a communication operation in one or more resources of a first set of resources, wherein the resources of the first set of resources are selected in a selection order from a second set of resources larger than the first set of resources, and wherein the selection order for the first set of resources is based on at least one of a periodicity of the search space set, a Downlink Control Information (DCI) format of the search space set, a starting symbol of the search space set, a component carrier type, a component carrier index, or an occasion index.

Description

Physical downlink control channel candidate selection method and system

Technical Field

This document relates generally to wireless communications.

Background

Wireless communication technology is pushing the world to an increasingly interconnected and networked society. The rapid growth of wireless communications and advances in technology have led to greater demands for capacity and connectivity. Other aspects such as energy consumption, equipment cost, spectral efficiency and latency are also important to meet the needs of various communication scenarios. Next generation systems and wireless communication technologies need to provide reliable communication of control information to support enhanced services and applications as compared to existing wireless networks.

Disclosure of Invention

This document relates to methods, systems, and apparatus for Physical Downlink Control Channel (PDCCH) candidate selection. Using the disclosed techniques, embodiments can perform PDCCH candidate selection by reducing the number of blind detection attempts that must be performed in current implementations of Long Term Evolution (LTE) and New Radio (NR) devices.

In one exemplary aspect, a method of wireless communication is disclosed. The method, which may be implemented at a Base Station (BS) or a User Equipment (UE), includes performing a communication operation in one or more resources of a first set of resources, wherein resources of the first set of resources are selected in a selection order from a second set of resources larger than the first set of resources, and wherein the selection order for the first set of resources is based on at least one of a period of a search space set, a Downlink Control Information (DCI) format of the search space set, a starting symbol of the search space set, a component carrier type, a component carrier index, or an opportunity index.

In another exemplary aspect, a method of wireless communication is disclosed. The method, which may be implemented at a Base Station (BS) or a User Equipment (UE), includes performing a communication operation in one or more resources of a first set of resources, wherein a second set of resources includes the first set of resources and a third set of resources, and resources of the first set of resources are non-overlapping with resources of a third set of resources, wherein resources of the third set of resources are selected in a selection order from the second set of resources, and wherein the selection order for the third set of resources is based on at least one of a periodicity of the search space set, a Downlink Control Information (DCI) format of the search space set, a starting symbol of the search space set, a component carrier type, a component carrier index, or an opportunity index.

In yet another exemplary aspect, the above-described method is implemented in the form of processor executable code and stored in a computer readable program medium.

In yet another exemplary embodiment, an apparatus configured or operable to perform the above method is disclosed.

The above aspects and other aspects and embodiments thereof are described in more detail in the accompanying drawings, description and claims.

Drawings

Fig. 1 illustrates an example of a Base Station (BS) and a User Equipment (UE) in wireless communication, in accordance with some embodiments of the disclosed technology.

Fig. 2 illustrates an example of an overloaded set of search spaces.

Fig. 3A and 3B show examples of the organization of PDCCH candidates in search space sets, aggregation levels, occasions, and slots.

Fig. 4 shows an example calculation of the values of priority levels for PDCCH candidate selection in a single set of search spaces and at a single aggregation level.

Fig. 5 shows an example of priority levels calculated for PDCCH candidates of multiple search space sets at a single aggregation level.

Fig. 6 shows an example process of PDCCH candidate selection at a base station.

Fig. 7 shows an example process of PDCCH candidate selection at a terminal.

Fig. 8A and 8B show examples of PDCCH candidate selection.

Fig. 9A and 9B show another example of PDCCH candidate selection.

Fig. 10A and 10B show still another example of PDCCH candidate selection.

Fig. 11 shows an example of PDCCH candidates with interleaving indices in a single search space set and at a single aggregation level at one occasion.

Fig. 12A and 12B show examples of priority levels calculated for PDCCH candidates for multiple search space sets and multiple aggregation levels.

Fig. 13A and 13B illustrate examples of PDCCH candidate selection based on priority levels.

Fig. 14 shows an example calculation of interleaving values for priority levels for PDCCH candidate selection in a single set of search spaces and at a single aggregation level.

Fig. 15A and 15B are examples of interleaving priority levels for PDCCH candidates for multiple search space sets at multiple aggregation levels.

Fig. 16A and 16B illustrate another example of PDCCH candidate selection based on priority levels.

Fig. 17 shows another example of priority levels for PDCCH candidate selection in a single set of search spaces and at a single aggregation level.

Fig. 18 shows another example of PDCCH candidate selection based on priority levels.

Fig. 19 shows an example of a wireless communication method for PDCCH candidate selection.

FIG. 20 is a block diagram representation of a portion of an apparatus that may implement the methods or techniques described in this patent document.

Detailed Description

In LTE and NR, downlink Control Information (DCI) is carried by a Physical Downlink Control Channel (PDCCH), and in general, a base station selects one PDCCH candidate among a plurality of PDCCH candidates as a final PDCCH channel. The terminal does not know which of the plurality of PDCCH candidates was selected by the base station, e.g., which PDCCH candidate was ultimately selected for transmission of downlink control information. Therefore, the terminal needs to attempt PDCCH demodulation and decoding on multiple PDCCH candidates one by one.

Fig. 1 shows an example of a wireless communication system including a BS 120 and one or more User Equipments (UEs) 111, 112 and 113. In some embodiments, the BS may transmit DCI through a PDCCH (141, 142, 143) to a UE, which blindly detects various PDCCH candidates in order to receive the DCI. Once the connection is established, the UE may transmit information to the BS (131, 132, 133). The UE may be, for example, a smartphone, a tablet, a mobile computer, a machine to machine (M2M) device, an Internet of things (IoT) device, and so on.

The plurality of PDCCH candidates are typically distributed under a plurality of aggregation levels, and each aggregation level typically includes a plurality of PDCCH candidates. Aggregation Level (AL) refers to the number of Control Channel Elements (CCEs) included in a PDCCH candidate. For example, if the aggregation level is 4, each PDCCH candidate at this aggregation level consists of 4 CCEs. In NR, a CCE consists of 6 Resource Element Groups (REGs), and each REG consists of 12 Resource Elements (REs).

PDCCH-related concepts that provide context for embodiments of the disclosed technology include a control resource set (CORESET) and a search space set. CORESET is mainly used to determine the frequency domain range of the PDCCH transmitted by the base station and the PDCCH detected by the terminal, and the number of symbols occupied by the PDCCH channel. CORESET may also include the following parameters:

control resource ID

Frequency domain resources

Duration (1, 2 or 3)

REG bundle size (2, 3, or 6)

Precoder-granularity (REG bundle size or contiguous Resource Blocks (RB) within CORESET)

CCE to REG mapping type (interleaved or non-interleaved)

Interleaver-row (2, 3 or 6)

Shift index of interleaver (0-274)

TCI State PDCCH (K ≦ MTCI-RS set configuration list)

DMRS scrambling sequence initialization value

The search space set is mainly used to determine which aggregation levels the PDCCH channel may use, the number of PDCCH candidates at a particular aggregation level, and information such as PDCCH periodicity and time domain position. The set of search spaces may contain the following parameters:

·CORESET ID

sign of CSS

DCI format parameters

Monitoring the periodicity of the slot(s)

Monitoring the offset of the time slot(s) ((0, 1, \8230;, N-1) in order to monitor the periodicity of N)

Symbol within a monitoring slot (14 bit bitmap)

AL =1, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =2, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =4, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =8, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =16, number of candidates (0, 1,2,3, 4, 5, 6, 8)

In LTE and NR systems, which are examples of carrier aggregation systems, one base station may transmit control and/or data information to one user equipment on different carriers at the same time, where each of these carriers is referred to as a component carrier. For one UE, one component carrier may include multiple bandwidth parts (BWPs). However, the base station typically only transmits control information and/or data information to the user equipment on one of these bandwidth parts of one component carrier. The BWP actually used to transmit the control information and/or the data information for a given time is referred to as an active BWP. Similarly, BWPs for initial access and for future communications may be referred to as an initial access bandwidth portion and a target bandwidth portion, respectively.

In an exemplary embodiment, the maximum number of CORESET in BWP may be 3, the maximum number of search space set in BWP may be 10, and there is a search space set corresponding to CORESET.

In some embodiments, the PDCCH periods in different sets of search spaces may be different. When multiple search space sets are located in the same slot (as shown in fig. 2), the total number of PDCCH candidates over the slot will increase significantly, as will the number of PDCCH blind detections. Fig. 2 shows some time slots that are overloaded due to a terminal searching for the same time slot in search space 1 and search space 2. This results in a significant increase in the number of CCEs required for channel estimation. Therefore, the number of PDCCH candidates in each search space and/or the number of CCEs required for channel estimation may exceed the capability supported by the User Equipment (UE).

Embodiments of the disclosed technology provide embodiments for selecting a selection order of PDCCH candidates to ensure that the number of PDCCH candidates and/or the number of CCEs required by the terminal to perform channel estimation does not exceed the capability of the UE. Section headings are used in this document to improve readability of the description, and do not limit the discussion or embodiments in any way to individual sections.

Brief summary of exemplary embodiments of the disclosed technology

In one example, the number of PDCCH candidates configured by the base station may exceed the capability of the UE (e.g., 44 PDCCH blind detection), or the number of CCEs corresponding to the number of PDCCH candidates configured by the base station may exceed the capability of the UE (e.g., channel estimation of a UE supporting up to 48 CCEs).

In one slot, if the number of PDCCH candidates configured by the base station exceeds a first threshold or if the number of CCEs corresponding to the number of PDCCH candidates configured by the base station exceeds a second threshold, both the base station and the terminal discard some PDCCH candidates according to a rule such that the number of reserved PDCCH candidates does not exceed the first threshold and the number of CCEs corresponding to the reserved PDCCH candidates does not exceed the second threshold.

The base station may select one or more PDCCH candidates among the remaining PDCCH candidates for transmission of the PDCCH.

Alternatively, the base station and the terminal may re-determine the locations of CCEs of PDCCH candidates in the CCE set corresponding to the reserved PDCCH candidates according to a certain rule. Then, one or more PDCCH candidates are selected from the excluded PDCCH candidates (unreserved PDCCH candidates) to be used for transmission of downlink control information.

Example embodiments of selecting an order of reserved PDCCH candidates

Method 1.In some embodiments, the selection order of PDCCH candidates is defined as:

(1) Classifying according to the type of the search space set;

(2) In the search space set type, selecting PDCCH candidates in N ≧ 1 round in descending order of Aggregation Level (AL); and

(3) The PDCCH candidates are selected in ascending order of search space set identifiers (or IDs) at the same aggregation level.

As described above, the PDCCH candidates are selected until a first threshold is exceeded, which may correspond to a maximum capability of the terminal or UE.

As an example, and assuming a UE-specific search space (USS) set type, the search space may correspond to two search space sets (as shown in fig. 3A and 3B), both in slot n. For the ith UE, the search space is configured as follows:

for search space set 3, the number of PDCCH candidates configured at aggregation level {1,2,4,8, 16} is {6, 0} respectively, and this corresponds to 4 occasions on slot n, as shown in the left part of FIGS. 3A and 3B.

For search space set 5, the number of PDCCH candidates configured under aggregation level {1,2,4,8, 16} is {6, 0} respectively, and this corresponds to 2 occasions on slot n, as shown in the right part of FIGS. 3A and 3B.

The order in which PDCCH candidates are selected (or equivalently "added") in a search space set type, such as a USS type search space set, may be determined according to the rules defined in method 1.

The candidates selected by the base station from the original PDCCH candidate set in the slot are referred to as reserved candidates. The remaining PDCCH candidates that are not selected are referred to as excluded PDCCH candidates.

Upon determining that some of the excluded PDCCH candidates correspond to CCEs in a new Control Channel Element (CCE) set, the base station may select some or all of the excluded PDCCH candidates. In these cases, one of the following procedures will be used:

(A) The base station selects some or all of the reserved PDCCH candidates and transmits downlink control information to the terminal on one or more physical downlink control channels using the selected reserved PDCCH candidates, or

(B) The base station selects some or all of the reserved PDCCH candidates, selects some or all of the previously excluded PDCCH candidates that correspond to CCEs in the new CCE set, and transmits downlink control information to the terminal on one or more physical downlink control channels using the selected reserved PDCCH candidates and the selected previously excluded PDCCH candidates.

In some embodiments, in either of the above two embodiments, the order of PDCCH candidates added at the aggregation level L of the search space set s (or equivalently, the order of selection of PDCCH candidates) may be further based on:

reordering the occasion indices (PDCCH candidate monitoring times) in the slot using an interleaving matrix, and/or

Using the above-described reordering rules, one PDCCH candidate is added to each occasion at a time, until all PDCCH candidates at aggregation level L of the search space set s are added.

In some embodiments, in either of the two embodiments described above, the order of PDCCH candidates added to a certain occasion in slot n at aggregation level L of search space set s may be further based on:

reordering PDCCH candidate indices for this occasion using an interleaving matrix, and/or

Add PDCCH candidates after reordering them.

Method 2.In some embodiments, the order of selection of PDCCH candidates may be based on priority values. For aggregation level L on search space set s, all PDCCH candidates per opportunity in a slot may be numbered. For occasion index 0, the pdcch candidate index is m, and its corresponding value is: i = O _s X m + O, as shown in FIG. 4 for a single set of search spaces and a single aggregation level, and where O _s Is the number of opportunities in the slot for the search space set s.

The priority of a PDCCH candidate is defined as

Wherein +>

Is the number of candidates configured for aggregation level L in the search space set s, and O _s Is the number of opportunities in the slot for the search space set s. According to this definition, PDCCH candidates under a single aggregation level and in two different search space setsThe priority values are shown in fig. 5. In one example, the PDCCH candidates may be selected in ascending order of priority values.

In some embodiments, and based on priority, PDCCH candidates may be added to multiple occasions on aggregation level L in the same set s of search spaces. However, this may result in the addition of PDCCH candidates being no longer sequential with respect to their indices, as they may be added according to the reordering discussed above.

Example embodiments for PDCCH candidate reselection based on CCE location

In some embodiments, after the reserved PDCCH candidates are determined, the remaining PDCCH candidates are referred to as excluded PDCCH candidates. The excluded PDCCH candidates may include CCEs (e.g., 48 CCEs) that are part of the reserved PDCCH candidates, and thus the CCEs may be re-determined.

For an excluded PDCCH candidate, assuming it belongs to search space set s and its aggregation level is L, the CCEs of the excluded PDCCH candidate are reselected using one of the following criteria:

the set of CCEs made up of the reserved PDCCH candidates is divided into a plurality of resources, each resource comprising L CCEs, and the UE selects the resource having the smallest degree of overlap with the CCEs of the excluded PDCCH candidates.

The set of CCEs made up of reserved PDCCH candidates is divided into multiple resources, each resource comprising L CCEs, and the UE selects the resource with the lowest level of overlap with the CCEs of excluded PDCCH candidates with other aggregation levels L.

The CCE set consisting of reserved PDCCH candidates is divided into multiple resources, each resource comprising L CCEs, and the UE selects the resource with the largest PDCCH candidate distance from the aggregation level L of excluded PDCCH candidates.

The base station selects some or all of the PDCCH candidates among the reserved PDCCH candidates, selects one or more physical downlink control channel candidates from the PDCCH candidates, and transmits downlink control information to the terminal on the one or more selected physical downlink control channels.

Alternatively, the base station selects some or all of the reserved PDCCH candidates and the excluded PDCCH candidates, selects one or more physical downlink control channel candidates from the PDCCH candidates, and transmits downlink control information to the terminal on the one or more selected physical downlink control channels.

Example embodiments

A base station side:an example method of the base station side procedure is shown in fig. 6. As shown in fig. 6, the base station determines a PDCCH candidate set for slot n based on the configuration of higher layer parameters of the base station (block 610). For example, the base station may configure multiple search space sets, and the configuration parameters of each search space set have the following parameters:

·CORESET ID

sign of CSS

DCI format parameters

Monitoring the periodicity of the slot(s)

Symbol in a supervision Slot (14 bit bitmap)

AL =1, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =2, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =4, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =8, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =16, number of candidates (0, 1,2,3, 4, 5, 6, 8)

The base station determines a set of Physical Downlink Control Channel (PDCCH) candidates corresponding to a set of search spaces that the terminal needs to detect on slot n.

The base station then selects a reserved PDCCH candidate from the set of PDCCH candidates according to a predefined sequence. The number of these reserved PDCCH candidates is limited to not exceeding a first threshold (block 620).

In some embodiments, the base station selects the reserved PDCCH candidates according to the following predefined order:

(1) Selecting a PDCCH candidate by searching a spatial set type;

(3) For the n-th wheel (1)<＝n<= N), when aggregation levels are selected in descending order, PDCCH candidates having an aggregation level less than L are selected. Threshold O as the nth round progresses _s The following search space sets add one reserved PDCCH candidate to each occasion of each search space set in descending order of search space set identifier, aggregation level L in the search space set. This process is repeated if the number of PDCCH candidates is less than the first threshold.

In some embodiments, the base station selects some or all of the excluded PDCCH candidates and reselects CCEs for the excluded PDCCH candidates (block 630).

In some embodiments, the base station selects one or more PDCCH candidates from among the reserved PDCCH candidates and excluded PDCCH candidates for re-determining CCEs (block 640), and transmits downlink control information to the terminal (block 660).

In some embodiments, the base station selects one or more PDCCH candidates from the reserved PDCCH candidates (block 650) and sends downlink control information to the terminal (block 660).

A terminal side:an example method of the terminal-side procedure is shown in fig. 7. As shown in fig. 7, the terminal determines a PDCCH candidate set for slot n based on the configuration of higher layer parameters of the base station (block 710). For example, a base station may configure multiple search space sets, and the configuration parameters for each search space set may include the following:

·CORESET ID

sign of CSS

DCI format parameters

Monitoring the periodicity of the slot(s)

Symbol in a supervision Slot (14 bit bitmap)

AL =1, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =2, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =4, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =8, number of candidates (0, 1,2,3, 4, 5, 6, 8)

AL =16, number of candidates (0, 1,2,3, 4, 5, 6, 8)

The terminal determines a set of Physical Downlink Control Channel (PDCCH) candidates corresponding to a set of search spaces that the terminal needs to detect on slot n.

The terminal then determines the reserved PDCCH candidates from the set of PDCCH candidates in a predefined order. The number of these reserved PDCCH candidates is limited to not exceeding a first threshold (block 720).

In some embodiments, the terminal selects the reserved PDCCH candidates according to the following predefined order:

(1) Selecting a PDCCH candidate by searching a spatial set type;

In some embodiments, the terminal selects some or all of the excluded PDCCH candidates and reselects CCEs for the excluded PDCCH candidates (block 730).

In some embodiments, the terminal detects downlink control information carried on one or more PDCCH candidates from among the reserved PDCCH candidates and excluded PDCCH candidates for re-determining CCEs (block 740).

In some embodiments, the terminal detects DCI among the reserved PDCCH candidates (block 750).

Example embodiment 1: multiple occasions; adding one PDCCH at a time for one opportunity

A base station side:in some embodiments, the base station determines the reserved PDCCH candidate set as follows:

(1) Selecting a PDCCH candidate by searching a spatial set type;

(3) For the n-th wheel (1)<＝n<= N), when aggregation levels are selected in descending order, PDCCH candidates having an aggregation level less than L are selected. Threshold O as the nth round progresses _s The following search space sets add one reserved PDCCH candidate to each occasion of each search space set in ascending order of search space set identifier, aggregation level L in the search space set. If the number of PDCCH candidates is less than the first threshold, the process is repeated.

And the base station determines the PDCCH candidate set of the time slot n according to the configuration of the high-level parameters of the base station.

In slot n, the terminal may have multiple search space sets that need to be monitored, and the base station determines the PDCCH candidate sets corresponding to these same search space sets. The selection of reserved PDCCH candidates by the base station according to condition (A) as previously detailed as part of method 1 in this document is in particular performed in the search space s according to a predefined order of aggregation levels L, wherein the number of reserved PDCCH candidates that have been selected does not exceed a threshold value

Where alpha is the ratio of the number of channel estimates that can be performed by the terminal to the number of CCEs present in the current slot,

indicates rounding up, and->

Is the number of PDCCH candidates in the search space set s that correspond to the aggregation level L that are configured by the base station for the terminal, and O _s Is the number of occasions of the search space set s in the time slot.

O _s Is the number of PDCCH candidate monitoring times (occasions) in a slot n of the search space set s, where one PDCCH candidate monitoring time comprises one or more time domain symbols, and there may be overlapping time domain symbols between different PDCCH candidate monitoring times.

In some embodiments, the search space set type may be divided into a Common Search Space (CSS) type and a UE-specific search space (USS) type. Alternatively, the search space set type may be divided into a plurality of CSS types and one USS type. If one base station can transmit one DCI through one PDCCH candidate to a plurality of UEs in one search space set, the search space set is referred to as a Common Search Space (CSS) set. Otherwise, the set of search spaces is referred to as a UE (user equipment) -specific set of search spaces (USS). In one common search space set, one base station may transmit DCI for scheduling system information, paging information, slot frame format indication information, and/or TPC (transmitter power control) command information.

In some embodiments, the base station selects the reserved PDCCH candidates according to the search space set type. For example, the reserved PDCCH candidates may be selected in the order of CSS and then USS. Alternatively, the reserved PDCCH candidates may be selected in the order of CSS0, CSS of configuration 2-0, other CSS, USS. After the base station selects all the reserved PDCCH candidates for the previous search space set type, it selects the reserved PDCCH candidates for the next search space set type.

In some embodiments, the base station selects a reserved PDCCH candidate for the ith UE in the order of CSS and USS according to the search space type. After selecting all the reserved PDCCH candidates for the CSS, the base station selects the reserved PDCCH candidates for the USS. In one example, assuming that all reserved PDCCH candidates are selected for CSS, the number of CCEs corresponding to the selection of all reserved PDCCH candidates may be 20.

In an example, and assuming a USS set type, a search space set may include two search space sets: a search space set 3 and a search space set 5 (shown in fig. 3A and 3B), both in time slot n. For the ith UE, the search space is configured as follows:

for search space set 3, the number of PDCCH candidates configured under aggregation level {1,2,4,8, 16} is {6, 0} respectively, and this corresponds to 4 occasions on slot n, as shown in the left part of FIGS. 3A and 3B.

In some embodiments, the order of selection or addition of PDCCH candidates in the USS search space type is illustrated in fig. 8A and 8B, where the numbers in the PDCCH candidates shaded in fig. 8A and 8B represent consecutive reserved PDCCH candidates added in the USS search space type in the following order:

the first round of selecting the reserved PDCCH candidates in descending order of aggregation level is as follows:

* Selecting PDCCH candidates of Aggregation Level (AL) L = 2:

in the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s Of the search space. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, the first reserved PDCCH candidateOptions are added to search space set 3 and a second reserved PDCCH candidate is added to search space set 5.

In the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, a third reserved PDCCH candidate is added to search space set 3 and a fourth reserved PDCCH candidate is added to search space set 5.

In the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The set of search spaces that satisfies this condition is the set of search spaces 3. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, a fifth reserved PDCCH candidate is added to the search space set 3.

In the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The set of search spaces that satisfies this condition is the set of search spaces 3. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, the sixth reserved PDCCH candidate is added to the search space set 3.

In this example, the number of added reserved PDCCH candidates reaches a threshold of 6. The threshold is the sum of the number of occurrences of each search space set in the USS type search space set in slot n.

* Selecting PDCCH candidates of Aggregation Level (AL) L = 1:

in the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the round is less than a threshold O _s The set of search spaces. A set of search spaces that satisfies this condition is a set of search spaces3 and a search space set 5. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, the seventh PDCCH candidate is added to search space set 3 and the eighth PDCCH candidate is added to search space set 5.

In the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s Of the search space. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, a ninth reserved PDCCH candidate is added to search space set 3 and a tenth reserved PDCCH candidate is added to search space set 5.

In the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the round is less than a threshold O _s The set of search spaces. The set of search spaces that satisfies this condition is the set of search spaces 3. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, the eleventh reserved PDCCH candidate is added to the search space set 3.

In the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The set of search spaces that satisfies this condition is the set of search spaces 3. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, the 12 th reserved PDCCH candidate is added to the search space set 3.

In this example, the number of added reserved PDCCH candidates reaches a threshold of 6. The threshold is the sum of the number of occurrences in slot n for each of the sets of USS-type search spaces.

The second round selects the reserved PDCCH candidates in descending order of aggregation level as follows:

* Selecting PDCCH candidates of Aggregation Level (AL) L = 2:

in the second round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, a thirteenth reserved PDCCH candidate is added to search space set 3 and a fourteenth reserved PDCCH candidate is added to search space set 5.

In the second round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, a fifteenth reserved PDCCH candidate is added to search space set 3, and a sixteenth reserved PDCCH candidate is added to search space set 5.

In the second round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the round is less than the threshold O _s Of the search space. The set of search spaces that satisfies this condition is the set of search spaces 3. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Accordingly, the seventeenth reserved PDCCH candidate is added to the search space set 3, thereby exhausting the USS search space set type.

In this example, the number of CCEs corresponding to a PDCCH candidate selected using the above procedure is 28 CCEs. Suppose a PDCCH candidate added in a CSS search space set preceding a USS search space setThe number of the corresponding CCEs is selected to be 20, and thus, the total number of CCEs corresponding to the selected reserved PDCCH candidate is 20+28=48. Since the CCE has reached CCE threshold 48, USS search space set type PDCCH candidate selection is terminated.

In some embodiments, physical Downlink Control Channel (PDCCH) candidates selected by the base station from the original PDCCH candidate set in time slot n according to higher layer configuration parameters are referred to as reserved PDCCH candidates. The remaining PDCCH candidates that are not selected by the base station are referred to as excluded PDCCH candidates. The base station selects some or all of the excluded PDCCH candidates and reselects CCEs for the excluded PDCCH candidates.

In some embodiments, the base station selects one or more PDCCH candidates from among the reserved PDCCH candidates and the excluded PDCCH candidates to re-determine CCEs, and transmits downlink control information to the terminal.

In some embodiments, the base station selects one or more PDCCH candidates from the reserved PDCCH candidates and transmits downlink control information to the terminal.

A terminal side:in some embodiments, the terminal determines the reserved PDCCH candidate set as follows:

(1) Selecting a PDCCH candidate by searching a spatial set type;

(3) For the n-th wheel (1)<＝n<= N), when aggregation levels are selected in descending order, PDCCH candidates having an aggregation level less than L are selected. Threshold O as the nth round progresses _s The following search space sets add one reserved PDCCH candidate to each time instance of each search space set in ascending order of search space set identifier, aggregation level in the search space set. This process is repeated if the number of PDCCH candidates is less than the first threshold.

And the terminal determines the PDCCH candidate set of the time slot n according to the configuration of the high-level parameters of the base station.

In slot n, the terminal may have multiple search space sets that need to be monitored, and the base station determines the PDCCH candidate sets corresponding to these same search space sets. The selection of reserved PDCCH candidates by the terminal according to condition (A) as previously detailed as part of method 1 in this document is in particular performed in the search space s according to a predefined order of aggregation level L, wherein the number of reserved PDCCH candidates that have been selected does not exceed a threshold value

indicates rounding up, and->

O _s Is the number of PDCCH candidate monitoring times in slot n of the search space set s, where one PDCCH candidate monitoring time comprises one or more time domain symbols, and there may be overlapping time domain symbols between different PDCCH candidate monitoring times.

In some embodiments, the search space set type may be divided into a Common Search Space (CSS) type and a UE-specific search space (USS) type. Alternatively, the search space set type may be divided into a plurality of CSS types and one USS type. In these embodiments, the terminal selects the reserved PDCCH candidates according to the search space set type. For example, the reserved PDCCH candidates may be selected in the order of CSS and then USS. Alternatively, the reserved PDCCH candidates may be selected in the order of CSS0, CSS of configuration 2-0, other CSS, USS. After the base station selects all reserved PDCCH candidates for the previous search space set type, it selects reserved PDCCH candidates for the next search space set type.

In some embodiments, the terminal selects a reserved PDCCH candidate for the ith UE in order of CSS and USS according to the search space type. After selecting all the reserved PDCCH candidates for the CSS, the base station selects the reserved PDCCH candidates for the USS. In one example, assuming that all reserved PDCCH candidates are selected for CSS, the number of CCEs corresponding to the selection of all reserved PDCCH candidates may be 20.

In an example, and assuming the USS set type, the search space set may include two search space sets: a search space set 3 and a search space set 5 (shown in fig. 3A and 3B), both in time slot n. For the ith UE, the search space is configured as follows:

In some embodiments, the order of selection of PDCCH candidates or the order of addition of PDCCH candidates in the USS search space type is illustrated in fig. 8A and 8B, where the numbers in the PDCCH candidates shaded in fig. 8A and 8B represent consecutive reserved PDCCH candidates added in the USS search space type in the following order:

* Selecting PDCCH candidates of Aggregation Level (AL) L = 2:

in the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the round is less than a threshold O _s Search space ofAnd (4) collecting. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, a first reserved PDCCH candidate is added to search space set 3 and a second reserved PDCCH candidate is added to search space set 5.

In the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s Of the search space. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, a third reserved PDCCH candidate is added to search space set 3 and a fourth reserved PDCCH candidate is added to search space set 5.

In the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the round is less than a threshold O _s Of the search space. The set of search spaces that satisfies this condition is the set of search spaces 3. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, a fifth reserved PDCCH candidate is added to the search space set 3.

In this example, the number of added reserved PDCCH candidates reaches a threshold of 6. The threshold is the sum of the number of occurrences in slot n for each of the USS type search space sets.

* Selecting PDCCH candidates of Aggregation Level (AL) L = 1:

in the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the round is less than a threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, a seventh PDCCH candidate is added to search space set 3 and an eighth PDCCH candidate is added to search space set 5.

In the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The set of search spaces that satisfies this condition is the set of search spaces 3. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, the eleventh reserved PDCCH candidate is added to the search space set 3.

* Selecting PDCCH candidates of Aggregation Level (AL) L = 2:

In the second round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Thus, the fifteenth reserved PDCCH candidate is added to search space set 3 and the sixteenth reserved PDCCH candidate is added to search space set 5.

In the second round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s Of the search space. The set of search spaces that satisfies this condition is the set of search spaces 3. One reserved PDCCH candidate is added to each selected search space set in ascending order of search space set number. Accordingly, the seventeenth reserved PDCCH candidate is added to the search space set 3, thereby exhausting the USS search space set type.

In this example, the number of CCEs corresponding to a PDCCH candidate selected using the above procedure is 28 CCEs. Assume that the number of CCEs corresponding to PDCCH candidates in the CSS search space set preceding the USS search space set is 20, and thus, the total number of CCEs corresponding to the selected reserved PDCCH candidates is 20+28=48. Since the CCE has reached CCE threshold 48, USS search space set type PDCCH candidate selection is terminated.

In some embodiments, physical Downlink Control Channel (PDCCH) candidates selected by the terminal from the original PDCCH candidate set in time slot n according to higher layer configuration parameters are referred to as reserved PDCCH candidates. The remaining PDCCH candidates not selected by the terminal are referred to as excluded PDCCH candidates. The terminal selects some or all of the excluded PDCCH candidates and reselects CCEs for the excluded PDCCH candidates.

The terminal may detect DCI carried on a physical downlink control message for the reserved PDCCH candidates and the excluded PDCCH candidates.

Example embodiment 2: multiple occasions; adding all PDCCHs once in one opportunity

(1) Selecting a PDCCH candidate by searching a spatial set type;

(3) For the nth round (1 < = N), the PDCCH candidates are selected in ascending order of the search space set identifier when selecting aggregation levels in descending order, and for any aggregation level in the nth round. When one spatial search set is selecting (or adding) a candidate, multiple PDCCH candidates may be selected at this time.

In slot n, the terminal may have multiple search space sets that need to be monitored, and the base station determines the PDCCH candidate sets corresponding to these same search space sets. The selection of reserved PDCCH candidates by the base station according to condition (A) as previously detailed as part of method 1 in this document is specifically performed according to a predefined order of aggregation levels L in the search space s, wherein the number of reserved PDCCH candidates that have been selected does not exceed a threshold

indicating rounding up, <' > based on>

In some embodiments, the search space set type may be divided into a Common Search Space (CSS) type and a UE-specific search space (USS) type. Alternatively, the search space set type may be divided into a plurality of CSS types and one USS type. In these embodiments, the base station selects the reserved PDCCH candidates according to the search space set type. For example, the reserved PDCCH candidates may be selected in the order of CSS and then USS. Alternatively, the reserved PDCCH candidates may be selected in the order of CSS0, CSS of configuration 2-0, other CSS, USS. After the base station selects all the reserved PDCCH candidates for the previous search space set type, it selects the reserved PDCCH candidates for the next search space set type.

In some embodiments, the base station performs N ≧ 1 round selection of PDCCH candidates in descending order of aggregation level. For round N (1 < = N), the PDCCH candidates are selected in ascending order of search space set identifier when selecting aggregation levels in descending order, and for any aggregation level in round N. When one spatial search set is selecting (or adding) a candidate, multiple PDCCH candidates may be selected at this time.

In some embodiments, the base station selects a reserved PDCCH candidate for the ith UE in the order of CSS and USS according to the search space type. After all the reserved PDCCH candidates are selected for the CSS, the base station selects the reserved PDCCH candidates for the USS. In one example, assuming that all reserved PDCCH candidates are selected for the CSS, the number of CCEs corresponding to selecting all reserved PDCCH candidates may be 20.

For search space set 5, the number of PDCCH candidates configured at aggregation level {1,2,4,8, 16} is {6, 0} respectively, and this corresponds to 2 occasions on slot n, as shown in the right part of FIGS. 3A and 3B.

In some embodiments, the order of selection of PDCCH candidates or the order of addition of PDCCH candidates in the USS search space type is illustrated in fig. 9A and 9B, where the numbers in the PDCCH candidates shaded in fig. 9A and 9B represent consecutive reserved PDCCH candidates added in the USS search space type in the following order:

* Selecting PDCCH candidates of Aggregation Level (AL) L = 2:

in the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. PDCCH candidates are added for search space set 3 and search space set 5 in descending order of search space set identifiers. Adding X =4 PDCCH candidates for search space set 3; thus, the first to fourth PDCCH candidates are added. Adding X =2 PDCCH candidates for search space set 5; thus, the fifth and sixth PDCCH candidates are added.

* Selecting PDCCH candidates of Aggregation Level (AL) L = 1:

in the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the round is less than a threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. PDCCH candidates are added for search space set 3 and search space set 5 in descending order of search space set identifiers. Adding X =4 PDCCH candidates for search space set 3; thus, seventh to tenth PDCCH candidates are added. Adding X =2 PDCCH candidates for search space set 5; therefore, the eleventh and twelfth PDCCH candidates are added.

The second round of selecting the reserved PDCCH candidates in descending order of aggregation level is as follows:

* Selecting PDCCH candidates of Aggregation Level (AL) L = 2:

in the second round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the round is less than the threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. PDCCH candidates are added for search space set 3 and search space set 5 in descending order of search space set identifiers. Adding X =4 PDCCH candidates for search space set 3; thus, thirteenth to sixteenth PDCCH candidates are added. Adding X =1 PDCCH candidates for the search space set 5; thus, a seventeenth PDCCH candidate is added.

In this example, the number of CCEs corresponding to a PDCCH candidate selected using the above procedure is 28 CCEs. Assume that the number of CCEs corresponding to PDCCH candidates in the CSS search space set that precedes the USS search space set is 20, and thus, the total number of CCEs corresponding to the selected reserved PDCCH candidate is 20+28=48. Because the CCE has reached the CCE threshold 48, USS search space set type PDCCH candidate selection is terminated.

(1) Selecting a PDCCH candidate by searching a spatial set type;

In slot n, the terminal may have multiple search space sets that need to be monitored, and the base station determines the PDCCH candidate sets corresponding to these same search space sets. The selection of reserved PDCCH candidates by the terminal according to condition (a) in this embodiment (as detailed previously in this document as part of method 1) is specifically performed according to a predefined order of aggregation levels L in the search space s, wherein the number of reserved PDCCH candidates that have been selected does not exceed a threshold.

indicates rounding up, and->

In some embodiments, the search space set type may be divided into a Common Search Space (CSS) type and a UE-specific search space (USS) type. Alternatively, the search space set type may be divided into a plurality of CSS types and one USS type. In these embodiments, the terminal selects the reserved PDCCH candidates according to the search space set type. For example, the reserved PDCCH candidates may be selected in the order of CSS and then USS. Alternatively, the reserved PDCCH candidates may be selected in the order of CSS0, CSS of configuration 2-0, other CSS, USS. After the terminal selects all the reserved PDCCH candidates for the previous search space set type, it selects the reserved PDCCH candidates for the next search space set type.

In some embodiments, the terminal selects PDCCH candidates in descending order of aggregation level by N ≧ 1. For the nth round (1 < = N), the PDCCH candidates are selected in ascending order of the search space set identifier when selecting aggregation levels in descending order, and for any aggregation level in the nth round. When one spatial search set is selecting (or adding) a candidate, multiple PDCCH candidates may be selected at this time.

In some embodiments, the search space set type may be divided into a Common Search Space (CSS) type and a UE-specific search space (USS) type. Alternatively, the search space set type may be divided into a plurality of CSS types and one USS type. In these embodiments, the base station selects the reserved PDCCH candidates according to the search space set type. For example, the reserved PDCCH candidates may be selected in the order of CSS and USS. Alternatively, the reserved PDCCH candidates may be selected in the order of CSS0, CSS of configuration 2-0, other CSS, USS. After the base station selects all reserved PDCCH candidates for the previous search space set type, it selects reserved PDCCH candidates for the next search space set type.

In some embodiments, the terminal selects a reserved PDCCH candidate for the ith UE in order of CSS and USS according to the search space type. After all the reserved PDCCH candidates are selected for the CSS, the base station selects the reserved PDCCH candidates for the USS. In one example, assuming that all reserved PDCCH candidates are selected for CSS, the number of CCEs corresponding to the selection of all reserved PDCCH candidates may be 20.

* Selecting PDCCH candidates of Aggregation Level (AL) L = 2:

in the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. PDCCH candidates are added for search space set 3 and search space set 5 in descending order of search space set identifier. Adding X =4 PDCCH candidates for search space set 3; thus, the first to fourth PDCCH candidates are added. Adding X =2 PDCCH candidates for search space set 5; thus, the fifth and sixth PDCCH candidates are addedAnd (4) selecting.

* Selecting PDCCH candidates of Aggregation Level (AL) L = 1:

in the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. PDCCH candidates are added for search space set 3 and search space set 5 in descending order of search space set identifiers. Adding X =4 PDCCH candidates for search space set 3; thus, seventh to tenth PDCCH candidates are added. Adding X =2 PDCCH candidates for search space set 5; thus, eleventh and twelfth PDCCH candidates are added.

* Selecting PDCCH candidates of Aggregation Level (AL) L = 2:

in the second round of selection, the selected search space set type is such that the number of reserved PDCCH candidates added in the current round is less than a threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. PDCCH candidates are added for search space set 3 and search space set 5 in descending order of search space set identifiers. Adding X =4 PDCCH candidates for search space set 3; thus, thirteenth to sixteenth PDCCH candidates are added. Adding X =1 PDCCH candidates for the search space set 5; thus, a seventeenth PDCCH candidate is added.

In this example, the number of CCEs corresponding to a PDCCH candidate selected using the above procedure is 28 CCEs. Assume that the number of CCEs corresponding to PDCCH candidates in a CSS search space set preceding the USS search space set is 20, and thus, the total number of CCEs corresponding to the selected reserved PDCCH candidates is 20+28=48. Because the CCE is alreadyThe CCE threshold 48 is reached, so USS search space set type PDCCH candidate selection is terminated.

The terminal may detect DCI carried on a physical downlink control message of the reserved PDCCH candidate and the excluded PDCCH candidate.

Example embodiment 3: opportunity to add PDCCH according to interleaving matrix

A base station side:in some embodiments, the occasion (PDCCH candidate monitoring time) indices in the slot may be reordered using an interleaving matrix, and PDCCH candidates may be sequentially selected according to the interleaved occasion indices each time in an occasion (and until all PDCCH candidates at aggregation level L of the search space set s have been selected).

In some embodiments, the base station determines the reserved PDCCH candidate set as follows:

(1) Selecting a PDCCH candidate by searching a spatial set type;

(3) For the nth round (1 < = N), when aggregation levels are selected in descending order, and for any aggregation level in the nth round, PDCCH candidates are selected in descending order of search space set identifiers. When one spatial search set is selecting (or adding) a candidate, multiple PDCCH candidates may be selected at this time.

In some embodiments, the base station selects a reserved PDCCH candidate for the ith UE in the order of CSS and USS according to the search space type. After all the reserved PDCCH candidates are selected for the CSS, the base station selects the reserved PDCCH candidates for the USS. In one example, assuming that all reserved PDCCH candidates are selected for CSS, the number of CCEs corresponding to the selection of all reserved PDCCH candidates may be 20.

Within the search space set type, the base station performs N ≧ 1 round selection of PDCCH candidates in descending order of Aggregation Level (AL). For the nth round (1 < = N), when aggregation levels are selected in descending order, and for any aggregation level in the nth round, PDCCH candidates are selected in descending order of search space set identifiers. When one spatial search set is selecting (or adding) a candidate, multiple PDCCH candidates may be selected at this time.

In some embodiments, for search space set 3, the timing indices 1 to 4 are read into the interleaver matrix row by row to derive the following:

1	2
		3	4

the output of the interleaver matrix is read column by column, where the order of the columns is 1, 1+ O _s /2、2、2+O _s /2、……、O _s /2、O _s Wherein in the present example O _s And =4. Thus, the output of the interleaver matrix is {1,3,2,4}. Similarly, for search space set 5, the output of the interleaver matrix is {1,2}.

Thus, the order of selection of PDCCH candidates or the order of adding PDCCH candidates in the USS search space type is shown in fig. 10A and 10B, where the numbers in the PDCCH candidates shaded in fig. 10A and 10B represent consecutive reserved PDCCH candidates added in the USS search space type in the following order:

* Selecting PDCCH candidates of Aggregation Level (AL) L = 2:

in the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the current round is less than the threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. PDCCH candidates are added for search space set 3 and search space set 5 in descending order of search space set identifier. For search space set 3, one PDCCH candidate is added to each occasion in the order {1,3,2,4} based on the output of the interleaver matrix, and thus, the first to fourth PDCCH candidates are added. For search space set 5, and based on the order {1,2}, fifth and sixth PDCCH candidates are added.

* Selecting PDCCH candidates of Aggregation Level (AL) L = 1:

in the first round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the round is less than a threshold

The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. PDCCH candidates are added for search space set 3 and search space set 5 in descending order of search space set identifiers. For search space set 3, one PDCCH candidate is added to each occasion in the order {1,3,2,4} based on the output of the interleaver matrix, and thus, seventh to tenth PDCCH candidates are added. For search space set 5, and based on the order {1,2}, the eleventh and twelfth PDCCH candidates are added.

* Selecting PDCCH candidates of Aggregation Level (AL) L = 2:

in the second round of selection, the selected search space set is such that the number of reserved PDCCH candidates added in the round is less than the threshold O _s The set of search spaces. The search space sets that satisfy this condition are the search space set 3 and the search space set 5. PDCCH candidates are added for search space set 3 and search space set 5 in descending order of search space set identifiers. For search space set 3, one PDCCH candidate is added to each occasion in the order {1,3,2,4} based on the output of the interleaver matrix, and thus, thirteenth to sixteenth PDCCH candidates are added. For search space set 5, and based on the order {1,2}, a seventeenth PDCCH candidate is added.

In this example, the number of CCEs corresponding to a PDCCH candidate selected using the above procedure is 28 CCEs. Assume that the number of CCEs corresponding to PDCCH candidates added in the CSS search space set prior to the USS search space set is 20, and thus, the total number of CCEs corresponding to the selected reserved PDCCH candidates is 20+28=48. Because the CCE has reached the CCE threshold 48So USS search space set type PDCCH candidate selection is terminated.

Example embodiment 4: adding PDCCH according to interleaving matrix within one opportunity

A base station side:in some embodiments, the occasion (PDCCH candidate monitoring time) indices in a slot may be reordered using an interleaving matrix, and PDCCH candidates may be selected at each time in an occasion (and until all PDCCH candidates at aggregation level L of the search space set s have been selected) according to the interleaved occasion index order.

Represents the number of physical downlink control channel candidates in the search space set s that are configured for the terminal by the base station corresponding to the aggregation level L. In the present example, is selected>

And the search space s in slot n and the PDCCH candidate index (denoted as m) in aggregation level L are shown in fig. 11.

In this embodiment, the PDDCH candidate index is read row by row into the interleaver matrix to derive the following:

0	1	2	3
				4	5	6	7

the output of the interleaver matrix is read column by column, wherein the order of the columns is

Thus, the ordering of PDCCH candidate indices after the interleaving matrix is 0,4,2,6,1,5,3, 7.

This is the order used to select PDCCH candidates in slot n according to the search space set s and aggregation level L. For example, if only 6 PDCCH candidates are to be selected, the index of the reserved PDCCH candidates will be {0,4,2,6,1,5}.

In some embodiments, the intra-slot index of the slot n search space set s is used to cyclically shift the PDCCH candidate index output after the interleaving matrix has been used to reorder the indices. In an example, PDCCH candidate index output of the interleaving matrix may be cyclically shifted to the left by Os mod

In whichO _s Is the index of the search space set s at time slot n. Therefore, the base station may add PDCCH candidates to the timing on slot n according to the cyclically shifted PDCCH candidate index order.

Example embodiment 5: opportunity to add PDCCH based on priority value

A base station side:in some embodiments, the base station may base the index (m), the occasion index (O), and the index (m) of the PDCCH candidate

To define a priority value for the PDCCH candidates. The priority values may be used to determine the order in which the PDCCH candidates are selected.

In some embodiments, the base station selects a reserved PDCCH candidate for the ith UE in the order of CSS and USS according to the search space type. After all the reserved PDCCH candidates are selected for the CSS, the base station selects the reserved PDCCH candidates for the USS.

In some embodiments, all PDCCH candidates of interest are numbered for aggregation level L and search space set s. A value of each of the PDCCH candidate indices may be calculated as I = O _s X m + O, where O is the timing index, O _s Is a set of search spacesThe number of occasions in the sum, and m is the number of PDCCH candidates in the set of occasion search spaces with index O. In some embodiments, the priority is defined as:

wherein->

Is the number of PDCCH candidates configured for the base station for aggregation level L in the search space set s.

Fig. 4 shows the values I for the set s of search spaces and the aggregation level L.

Fig. 12A and 12B show priority values of the search space set 3 and the search space set 5 at the aggregation levels L =2 and L = 1.

In some embodiments, the base station may select PDCCH candidates in descending order of priority values. For the same priority value, the reserved PDCCH candidates are selected in descending order of aggregation level. For the same priority value and the same aggregation level, the PDCCH candidates are selected in descending order of the search space set identifiers. Based on these rules, and in the case where the base station selects 17 PDCCH candidates, the selected PDCCH candidates are shown in fig. 13A and 13B.

After 17 PDCCH candidates have been selected, the total number of selected PDCCH candidates and/or the number of CCEs corresponding to the selected PDCCH candidates reaches their respective thresholds, and the selection of the remaining PDCCH candidates is terminated.

Example embodiment 6: opportunity addition PDCCH based on interleaved priority value

A base station side:in some embodiments, the base station may use a PDCCH-based candidate index (m), an occasion index (O), and

to select PDCCH candidates. The priority values may be used to determine the order in which the PDCCH candidates are selected, but after they are interleaved. In other words, O' is a timing index in the interleaved set of timing indexes. Each in PDCCH candidate indexThe value of one may be calculated as I = O _s X m + O ', where O' is the timing index, O _s Is the number of occasions in the search space set s, and m is the number of PDCCH candidates in the search space set at occasions with index O. In some embodiments, the priority is defined as: />

Wherein->

In some embodiments, the timing indices 1 to 4 are read into the interleaver matrix row by row for the search space set s at time slot n to derive the following:

0	1
		2	3

the output of the interleaver matrix is read column by column, where the order of the columns is 1, 1+ O _s /2、2、2+O _s /2、……、O _s /2、O _s . Thus, for an input of {0,1,2,3}, the output of the interleaver matrix is {0,2,1,3}.

Fig. 14 shows the values calculated for PDCCH candidates in slot n for the search space set s and aggregation level L and according to the priority and interleaving example described above.

Fig. 15A and 15B show priority values of the search space set 3 and the search space set 5 at the aggregation levels L =2 and L = 1.

In some embodiments, the base station may select PDCCH candidates in descending order of priority values. For the same priority value, the reserved PDCCH candidates are selected in descending order of aggregation level. For the same priority value and the same aggregation level, the PDCCH candidates are selected in descending order of the search space set identifiers. Based on these rules, and in the case where the base station selects 17 PDCCH candidates, the selected PDCCH candidates are shown in fig. 16A and 16B.

Example embodiment 7: opportunities to add PDCCH based on priority value and s, L

to select PDCCH candidates. For search space set s and aggregation level L, the priority value of s, L may be defined as the minimum of the priority values corresponding to all PDCCH candidates in search space s at aggregation level L, and is the priority of s, L.

The base station selects s, L in descending order of the priority values of s, L, and selects PDCCH candidates having an aggregation level L in the search space set s. After s, L is selected as the reserved PDCCH candidate, the minimum priority value is deleted from s, L, and the minimum priority value corresponding to a PDCCH candidate having all the undeleted priority values in s, L is selected as a new (or updated) priority value of s, L. The base station continues to select s, L in descending order of the priority values of s, L and selects PDCCH candidates with aggregation level L in the search space set s.

In some embodiments, for s, L having the same priority value, the reserved PDCCH candidates are selected in descending order of aggregation level L. For s, L of the same priority value and the same aggregation level L, PDCCH candidates are selected in descending order of the search space set identifier.

In some embodiments, for aggregation level L and search space sets, all PDCCH candidates of interest are numbered. A value of each of the PDCCH candidate indices may be calculated as I = O _s X m + O, where O is the timing index, O _s Is the number of occasions in the search space set s, and m is the number of PDCCH candidates in the search space set at occasions with index O. In some embodiments, the priority is defined as:

wherein +>

Fig. 4 shows the values I for the set of search spaces s and the aggregation level L.

In some embodiments, for search space set s and aggregation level L, the priority value of s, L is the minimum of the priority values corresponding to all PDCCH candidates in search space s at aggregation level L, and is the priority of s, L. Thus, the priority values in the set of search spaces s and at the aggregation level L are:

the priority value of { s, L } = {3,2} is 0;

a priority value of { s, L } = {5,2} is 0;

the priority value of { s, L } = {3,1} is 0; and

the priority value of s, L = {5,1} is 0.

In some embodiments, for { s, L } of the same priority value, the reserved PDCCH candidates are selected in ascending order of aggregation level L. For s, L of the same priority value, and if the aggregation level L is also the same, the PDCCH candidates are selected in ascending order of the search space set identifier s.

According to the rule defined above, s, L = {3,2} is first selected. After { s, L } = {3,2} is selected, one PDCCH candidate is added to { s, L } = {3,2}. In the present example, one PDCCH candidate is added in the interleaving order of 0,2,1,3 for the timing index of { s, L } = {3,2}. After adding the PDCCH candidates, the priority value of s, L = {3,2} (which is (0)) will be removed, and all the undeleted priorities in s, L } are selected. The minimum priority value 1/24 corresponding to a PDCCH candidate is a new priority value of { s, L } = {3,2}. After deleting the lowest priority value 0 of s, L } = {3,2}, the priority value of each PDCCH candidate on s, L } = {3,2} is shown in fig. 17.

Next, the reserved PDCCH candidates are continuously selected according to the above-described rule, and it is assumed that the order of adding PDCCH candidates with respect to the timing index is {0,2,1,3} at the aggregation level in the search space set 3. Similarly, for the aggregation level in search space set 5, the order of adding the timing indexes of PDCCH candidates is {0,1}.

Assuming the USS set type described above, 18 PDCCH candidates are selected and their locations are shown in fig. 18.

Fig. 19 shows an example of a wireless communication method 1900 for PDCCH candidate selection. The method 1900 includes, at step 910, performing a communication operation in one or more resources of a first set of resources. The second set of resources may include the first set of resources and a third set of resources such that resources in the first set of resources do not overlap with resources in the third set of resources. Additionally, a resource in a set of resources may include a sub-resource. In some embodiments, the resources may correspond to PDCCH candidates and the sub-resources may correspond to CCEs. In other embodiments, the second set of resources may correspond to PDCCH candidates, the first set of resources may correspond to reserved PDCCH candidates, and the third set of resources may correspond to excluded PDCCH candidates, as described in example embodiments 1 to 7.

In some embodiments, the resources in the first set of resources are selected from the second set of resources in a selection order. In other embodiments, the resources in the third set of resources are selected from the second set of resources in the order of selection.

In some embodiments, the selection order is based on at least one of a periodicity of the search space set, a DCI format of the search space set, a starting symbol of the search space set, a component carrier type, a component carrier index, or an occasion index. In other embodiments, the selection order is further based on at least one of an aggregation level, a number of resources in the second set of resources, a search space set identifier, a control resource set identifier, a number of blind decoding operations, a number of sub-resources, a search space set type, and a resource index in the second set of resources.

In some embodiments, the second set of resources may correspond to resources in a bandwidth part (BWP) of a component carrier in one slot. In an example, the bandwidth portion may be an active bandwidth portion, a target bandwidth portion, or an initial access bandwidth portion.

In some embodiments, the number of the first resource, the second resource, and the third resource may be less than respective thresholds. In an example, the threshold may be known a priori to the terminal and the base station. In another example, the threshold may be predetermined or may be indicated to the terminal via signaling from the base station. In some embodiments, the third threshold may be based at least on

And O _s Wherein->

Is the number of resources in a single set of search spaces and at a single aggregation level for an opportunity, and where O _s Is the number of occasions of a single set of search spaces.

In some embodiments, the selection order may be based on the rules specified in example embodiments 1 to 7. In an example, the selection order may be based on an ascending or descending order of one or more parameters. In another example, the selection order may be based on an interleaving order of one or more parameters. In the context of example embodiments 1 to 7, the order of selection of the plurality of parameters may be nested, e.g. the selection of a PDCCH candidate may be based on a first parameter and for the same value of the first parameter, the selection may be based on a second parameter.

In some embodiments, the selection of PDCCH candidates may be performed in multiple selection steps. For example, the first selection step may be based on a type of search space set (CSS or USS), the second selection step performed after the first selection step and within the type of search space set may be based on a type of cell (primary cell or one or more secondary cells) in which the wireless node is operating, the third selection step performed after the second selection step and within the type of cell may be based on an increasing order of component carrier indices (associated with BWP), the fourth selection step performed after the third selection step and for a given value of the component carrier indices may be based on a search space set period and a number of occasions to search the space set in one slot, and the fifth selection step performed after the fourth selection step and for a given value of the search space set period and the number of occasions to search the space set may be based on a decreasing order of aggregation levels.

In some embodiments, the selection order may be based on interleaving steps before or after the selection is made based on the parameters. Examples of selecting PDCCH candidates (which may be implemented using an interleaving matrix) based on interleaving are described in

example embodiments

3, 4 and 6. In an example, the interleaved output may be cyclically shifted based on values of other parameters.

In some embodiments, and based on the description in the "example embodiments for PDCCH candidate reselection based on CCE location" section, sub-resources (e.g., CCEs) in excluded resources may be compared to sub-resources of reserved resources, and those excluded resources are recombined into a set of resources that may then be used to transmit DCI information.

In some embodiments, the selection of PDCCH candidates may be sequential with respect to certain parameters, and in particular may be an ascending, descending, or interleaved order, as described in various examples in this document.

In some embodiments, the selection order may be based on priority values calculated for PDCCH candidates according to the search space set, the aggregation level and the occasion index, as described in example embodiments 5 to 7 in this document. In some described examples, priority values may optionally be interleaved before selecting resources based on the priority values.

Fig. 20 is a block diagram representation of a portion of an apparatus in accordance with some embodiments of the disclosed technology. The apparatus 2005, such as a base station or wireless device (or UE), may include processor electronics 2010, such as a microprocessor implementing one or more of the techniques presented in this document. The apparatus 2005 may include transceiver electronics 2015 to transmit and/or receive wireless signals via one or more communication interfaces, such as one or more antennas 2020. The device 2005 may include other communication interfaces for transmitting and receiving data. The device 2005 may include one or more memories (not explicitly shown) configured to store information such as data and/or instructions. In some implementations, the processor electronics 2010 can include at least a portion of the transceiver electronics 2015. In some embodiments, at least some of the disclosed techniques, modules, or functions (including method 1900) are implemented using apparatus 2005.

This specification and the drawings together are to be regarded as illustrative only, with the exemplification being meant to be exemplary, and is not intended to suggest an ideal or preferred embodiment unless otherwise indicated. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Additionally, use of "or" is intended to include "and/or" unless the context clearly indicates otherwise.

Some of the embodiments described herein are described in the general context of methods or processes, which may be implemented in one embodiment by a computer program product, embodied in a computer-readable medium, including computer-executable instructions, such as program code, executed by computers in networked environments. Computer-readable media may include removable and non-removable storage devices, including but not limited to Read Only Memory (ROM), random Access Memory (RAM), compact Disks (CDs), digital Versatile Disks (DVDs), and the like. Thus, a computer-readable medium may include a non-transitory storage medium. Generally, program modules may include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-or processor-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps or processes.

Some of the disclosed embodiments may be implemented as a device or module using hardware circuitry, software, or a combination thereof. For example, a hardware circuit implementation may include discrete analog and/or digital components integrated as part of a printed circuit board, for example. Alternatively or additionally, the disclosed components or modules may be implemented as Application Specific Integrated Circuits (ASICs) and/or Field Programmable Gate Array (FPGA) devices. Some embodiments may additionally or alternatively include a Digital Signal Processor (DSP), which is a special-purpose microprocessor with an architecture optimized for the operational requirements of digital signal processing associated with the disclosed functionality of the present application. Similarly, various components or sub-components within each module may be implemented in software, hardware, or firmware. Connections between modules and/or components within modules may be provided using any of the connection methods and media known in the art, including, but not limited to, communications over the internet, wired, or wireless networks using appropriate protocols.

While this document contains many specifics, these should not be construed as limitations on the scope of the claimed invention or of what may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this document in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination. Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results.

Only a few embodiments and examples are described and other implementations, enhancements and variations can be made based on what is described and illustrated in this disclosure.

Claims

1. A method for wireless communications implemented at a wireless node, comprising:

a communication operation is performed in one or more resources of the first set of resources,

wherein the resources in the first set of resources are selected in a selection order from a second set of resources larger than the first set of resources, and

wherein the selection order for the first set of resources is based on at least one of a periodicity of the search space set, a downlink control information, DCI, format of the search space set, a starting symbol of the search space set, a component carrier type, a component carrier index, or an occasion index,

wherein a subset of the first set of resources is sequentially selected from a single set of search spaces and a plurality of opportunities within a single aggregation level, and wherein the opportunity indices of the plurality of opportunities are interleaved prior to sequential selection.

2. The method of claim 1, wherein the subset of the first set of resources is selected sequentially from within a single set of search spaces and a single aggregation level and in one time slot, and wherein resources in each occasion under the single set of search spaces and the single aggregation level are reordered prior to sequential selection.

3. The method of claim 1, wherein the selection order is further based on at least one of an aggregation level, a number of resources in the second set of resources, a search space set identifier, a control resource set identifier, a number of blind decoding operations, a number of sub-resources, a search space set type, and an index of resources in the second set of resources.

4. The method of claim 1, wherein the second set of resources corresponds to resources in a bandwidth portion of a component carrier in one slot.

5. The method of claim 4, wherein the bandwidth portion is one of an active bandwidth portion, a target bandwidth portion, or an initial access bandwidth portion.

6. The method of claim 1, wherein the selection order is based on an ascending order of the component carrier indices.

7. The method of claim 1, wherein a number of first sets of resources is less than a first threshold, the first threshold being known a priori by the wireless node.

8. The method of claim 1, wherein each resource in the first set of resources comprises a sub-resource, and wherein a number of sub-resources in the first set of resources is less than a second threshold, the second threshold being known a priori by the wireless node.

9. The method of claim 1, wherein a number of the single set of search spaces and the first set of resources within the single aggregation level is less than a third threshold.

10. The method of claim 7, wherein the third threshold is based on

And O _s Wherein->

Is in a single search space set and a single opportunityThe amount of resources at the aggregation level, and wherein O _s Is the number of occasions of a single set of search spaces.

11. The method of claim 1, wherein the second set of resources corresponds to resources in both a primary cell of the wireless node and one or more secondary cells of the wireless node.

12. The method of claim 1, wherein the selection order is based on a decreasing order of a number of opportunities in a search space set in a time slot.

13. The method of claim 1, wherein the selection order is based on a descending order of periodicity of a set of search spaces.

14. The method of claim 1, wherein the selection order is based on an ascending order of starting symbol indices of a set of search spaces.

15. The method of claim 1, wherein the selection order is based on a period of the search space set and a number of occasions in the search space set in the time slot.

16. The method of claim 1, wherein the selection order is based on a type of search space set.

17. The method of claim 16, wherein within the selected type of search space, the selection order is further based on (a) a periodicity of the search space set and (b) a number of occasions to search the search space set in the time slot.

18. The method of claim 17, wherein the selection order is further based on a descending order of aggregation levels for a selected period of search space and a selected number of occasions of search space.

19. The method of claim 16, wherein the selection order is further based on a descending order of aggregation levels within the selected type of search space.

20. The method of claim 19, wherein the selection order is further based on an ascending order of search space set identifiers within a selected aggregation level.

21. The method of claim 16, wherein a type of search space set is selected from the group consisting of: a common search space set comprising downlink control information, DCI, formats 0-0 and 1-0, a common search space set comprising DCI formats 2-0, a common search space set comprising other DCI formats, and one or more user equipment, UE, specific search space sets.

22. The method of claim 1, wherein selecting according to the selection order comprises:

a first selection step, said first selection step being based on a type of search space set;

a second selection step, subsequent to the first selection step and within a type of the set of search spaces, the second selection step based on a type of cell in which the wireless node is operating;

a third selection step, subsequent to the second selection step and within the type of cell, the third selection step being based on an ascending order of the component carrier indices;

a fourth selection step that is subsequent to the third selection step and is based on a period of a search space set and a number of occasions of searching the space set in one slot for a given value of the component carrier index; and

a fifth selection step, subsequent to the fourth selection step and based on a descending order of aggregation levels, for a given value of the period of the set of search spaces and a given value of the number of occasions of the set of search spaces.

23. The method of claim 1, wherein selecting according to the selection order comprises:

a first selection step, based on a common set of search spaces including downlink control information, DCI format 0-0 and DCI format 1-0.

24. The method of claim 23, further comprising:

a second selection step, subsequent to the first selection step, based on another common set of search spaces that includes DCI formats 2-0 and does not include DCI formats 0-0 and DCI formats 1-0.

25. The method of claim 24, further comprising:

a third selection step, subsequent to the second selection step, based on a common search space including other DCI formats.

26. The method of claim 25, further comprising:

a fourth selection step, subsequent to the third selection step, the fourth selection step being based on a user equipment, UE, specific set of search spaces.

27. The method of claim 1, wherein the selection order is further based on a descending order of aggregation levels.

28. The method of claim 27, wherein the selection order is further based on an ascending order of search space set identifiers for a given aggregation level.

29. The method of claim 1, wherein the selection order is further based on an ascending order of search space set identifiers.

30. The method of claim 1, wherein the selection order is further based on an ascending order of resource indices in the second set of resources per opportunity at a single set of search spaces and aggregation level.

31. The method of claim 1, wherein the interleaving is based on having two rows and ceil (O) _s /2) interleaver matrix of columns, where Os is the number of occasions of a single set of search spaces in a slot, and where ceil (x) returns the smallest integer greater than x.

32. The method of claim 1, wherein the interleaving is based on an interleaver matrix with opportunity indices of 0,1, \8230;, O _s Are written to the interleaver matrix in rows with timing indexes defined as 1, 1+ ceil (O) _s /2)、2、2+ceil(O _s /2)、……、floor(O _s /2)、floor(O _s /2)+ceil(O _s /2)、floor(O _s Column-wise read from the interleaver matrix for column order of/2) +1, and wherein O _s Is the number of occasions of the single set of search spaces in a time slot.

33. The method of claim 1 wherein the interleaving is based on an interleaver matrix with timing indices 0,1, \8230, os being written to the interleaver matrix in rows with timing indices defined as 1, 1+ O _s /2、2、2+O _s /2、……、O _s /2、O _s Is read column by column from the interleaver matrix, and wherein O _s Is the number of occasions of the single set of search spaces in a time slot.

34. The method of claim 1, wherein the interleaving is based on an identity matrix.

35. The method of claim 1, wherein the interleaving is based on a definition of 0, ceil (O) _s /2)、1、1+ceil(O _s A sequence of timing indexes of (2), \8230; \8230, where O _s Is said single search space in a time slotThe number of occasions.

36. The method of claim 1, wherein the interleaving is based on definitions of 0, O _s 、2、O _s -1, \8230\8230, the sequence of timing indexes, wherein O _s Is the number of occasions of the single search space in a time slot.

37. The method of claim 2, wherein the reordering comprises an ascending order of resource indices in each occasion.

38. The method of claim 2, wherein the reordering comprises interleaving of resource indices in each occasion.

39. The method of claim 38, wherein the interleaving is based on having two rows and

an interleaver matrix of columns, wherein &>

Is the number of resources under the single set of search spaces and the single aggregation level and in each occasion, and wherein ceil (x) returns a minimum integer greater than x.

40. The method of claim 38, wherein a cyclic shift of the interleaved output is performed prior to the sequential selection, and wherein the cyclic shift is based on an opportunity index.

41. The method of claim 38, wherein the interleaving is based on an interleaver matrix, wherein resource indices

Is written row by row into the interleaver matrix, wherein a resource index is defined as

Is read column-wise from the interleaver matrix, wherein ∑ is @>

Is the amount of resources under the single set of search spaces and the single aggregation level and in each occasion.

42. The method of claim 38, wherein the interleaving is based on an interleaver matrix, wherein a resource index

Is written row-by-row into the interleaver matrix, wherein a resource index is defined to be {/or }>

Is read column-wise from the interleaver matrix, wherein ∑ is @>

43. The method of claim 38, wherein the interleaving is defined based on

The ordering of the resource indices of (a) is, wherein->

44. The method of claim 38, wherein the interleaving is defined based on

The ordering of the indices of the resources of (c), wherein +>

45. The method of claim 38, wherein the interleaving is defined based on

The ordering of the resource indices of (a) is, wherein->

46. The method of claim 38, wherein the interleaving is defined based on

The ordering of the resource indices of (a) is, wherein->

47. The method of claim 1, wherein the selection order is further based on

In an ascending order, wherein->

Is the amount of resources in an opportunity at a single set of search spaces and a single aggregation level.

48. The method of claim 1, wherein the selection order is further based on

In descending order of, wherein->

49. The method of claim 1, wherein the selection order is further based on a decreasing order of the degree of overlap of the sub-resources of each of the selected resources.

50. The method of claim 1, wherein priority values are assigned to one or more resources in the second set of resources, and wherein the selection order is based on an ascending, descending, or interleaved order of the priority values.

51. The method of claim 50, wherein the priority value is based on at least

And O _s Wherein->

Is the amount of resources under a single set of search spaces and a single aggregation level and in an opportunity, and wherein O _s Is the number of occasions of the single set of search spaces in a time slot.

52. The method of claim 51, wherein the priority values of the first subset of the second set of resources are the same, and wherein the first set of resources are selected from the first subset of the second set of resources in descending order of aggregation level.

53. The method of claim 52, wherein the aggregation levels of the second subset of the second set of resources are the same, and wherein the first set of resources are selected from the second subset of the second set of resources in ascending order of the search space set identifier.

54. The method of claim 1, wherein starting symbol indices for different occasion indices of a set of search spaces are different from each other within the set of search spaces.

55. The method of claim 1, wherein the first set of resources corresponds to reserved physical control channel, PDCCH, candidates.

56. The method of claim 1, wherein a resource in a first set of resources corresponds to a reserved physical control channel, PDCCH, candidate, wherein each resource in the first set of resources comprises one or more sub-resources, and wherein the one or more sub-resources correspond to a control channel element, CCE.

57. The method of claim 1, wherein the wireless node is a base station, and wherein performing the communication operation comprises transmitting control information in one or more resources of a first set of resources.

58. The method of claim 1, wherein the wireless node is a user equipment, and wherein performing the communication operation comprises performing detection in one or more resources of a first set of resources.

59. A method for wireless communications implemented at a wireless node, comprising:

wherein the second set of resources comprises a first set of resources and a third set of resources, wherein resources in the first set of resources do not overlap with resources in the third set of resources,

wherein the resources in the third set of resources are selected from the second set of resources in the selection order, and

wherein the selection order for the third set of resources is based on at least one of a periodicity of the search space set, a downlink control information, DCI, format of the search space set, a starting symbol of the search space set, a component carrier type, a component carrier index, or an occasion index,

wherein a subset of the third set of resources is sequentially selected from a single set of search spaces and a plurality of opportunities within a single aggregation level, and wherein the opportunity indices of the plurality of opportunities are interleaved prior to sequential selection.

60. The method of claim 59, wherein the selection order is further based on at least one of an aggregation level, a number of resources in the second set of resources, a search space set identifier, a control resource set identifier, a number of blind decoding operations, a number of sub-resources, a search space set type, and an index of resources in the second set of resources.

61. The method of claim 59, wherein the second set of resources corresponds to resources in a bandwidth portion of a component carrier in one slot.

62. The method of claim 61, wherein the bandwidth portion is one of an active bandwidth portion, a target bandwidth portion, or an initial access bandwidth portion.

63. The method of claim 59, wherein the selection order is based on an ascending order of the component carrier indices.

64. The method of claim 59, wherein the number of first sets of resources is less than a first threshold, the first threshold being known a priori by the wireless node.

65. The method of claim 59, wherein each resource in the first set of resources comprises a sub-resource, and wherein the number of sub-resources in the first set of resources is less than a second threshold, the second threshold being known a priori by the wireless node.

66. The method of claim 59, wherein a number of the single set of search spaces and the first set of resources within the single aggregation level is less than a third threshold.

67. The method of claim 64, in which the third threshold is based on

And O _s Wherein->

Is the amount of resources in a single set of search spaces and at a single aggregation level on a given occasion, and where O _s Is a single set of search spacesThe number of time of the synthesis.

68. The method of claim 59, wherein a second set of resources corresponds to resources in both a primary cell of the wireless node and one or more secondary cells of the wireless node.

69. The method of claim 59, wherein the selection order is based on a decreasing order of a number of opportunities in a search space set in a time slot.

70. The method of claim 59, wherein the selection order is based on a descending order of periodicity of a set of search spaces.

71. The method of claim 59, wherein the selection order is based on an ascending order of starting symbol indices of a set of search spaces.

72. The method of claim 59, wherein the selection order is based on a period of the set of search spaces and a number of occasions in the set of search spaces in a time slot.

73. The method of claim 59, wherein the selection order is based on a type of search space set.

74. The method of claim 73, wherein within a selected type of search space, the selection order is further based on (a) a periodicity of the search space sets and (b) a number of occasions to search the space sets in the time slot.

75. The method of claim 74, wherein the selection order is further based on a descending order of aggregation levels for a selected period of search space and a selected number of occasions of search space.

76. The method of claim 73, wherein the selection order is further based on a descending order of aggregation levels within the selected type of search space.

77. The method of claim 76, wherein the selection order is further based on an ascending order of search space set identifiers within the selected aggregation level.

78. The method of claim 73, wherein a type of search space set is selected from the group consisting of: a common search space set comprising downlink control information, DCI, formats 0-0 and 1-0, a common search space set comprising DCI formats 2-0, a common search space set comprising other DCI formats, and one or more user equipment, UE, specific search space sets.

79. The method of claim 59, wherein selecting according to the selection order comprises:

a fourth selection step, subsequent to the third selection step and for a given value of the component carrier index, the fourth selection step being based on a period of a search space set and a number of occasions to search the space set in one slot; and

a fifth selection step, subsequent to the fourth selection step and for a given value of the period of a set of search spaces and a given value of the number of occasions of a set of search spaces, the fifth selection step being based on a descending order of aggregation levels.

80. The method of claim 59, wherein selecting according to the selection order comprises:

a first selection step, based on a common set of search spaces comprising downlink control information, DCI, formats 0-0 and DCI formats 1-0.

81. The method of claim 80, further comprising:

a second selection step, subsequent to the first selection step, based on another common set of search spaces that includes DCI format 2-0 and does not include DCI format 0-0 and DCI format 1-0.

82. The method of claim 81, further comprising:

83. The method of claim 82, further comprising:

84. The method of claim 59, wherein the selection order is further based on a descending order of aggregation levels.

85. The method of claim 84, wherein the selection order is further based on an ascending order of search space set identifiers for a given aggregation level.

86. The method of claim 59, wherein the selection order is further based on an ascending order of search space set identifiers.

87. The method of claim 59, wherein the selection order is further based on an ascending order of resource indices in the second set of resources per opportunity at a single set of search spaces and aggregation level.

88. The method of claim 59, wherein the interleaving is based on having two rows and ceil (O) _s /2) interleaver matrix of columns, where Os is the number of occasions of a single set of search spaces in a slot, and where ceil (x) returns the smallest integer greater than x.

89. The method of claim 59, wherein the interleaving is based on an interleaver matrix with opportunity indices of 0,1, \8230;, O _s Are written to the interleaver matrix in rows with timing indexes defined as 1, 1+ ceil (O) _s /2)、2、2+ceil(O _s /2)、……、floor(O _s /2)、floor(O _s /2)+ceil(O _s /2)、floor(O _s Column-wise read from the interleaver matrix for column order of/2) +1, and wherein O _s Is the number of occasions of the single set of search spaces in a time slot.

90. The method of claim 59 wherein the interleaving is based on an interleaver matrix with timing indices 0,1, \8230; \8230, os are written to the interleaver matrix in rows with timing indices defined as 1, 1+, O + _s /2、2、2+O _s /2、……、O _s /2、O _s Is read column by column from the interleaver matrix, and wherein O _s Is the number of occasions of the single set of search spaces in a time slot.

91. The method of claim 59, wherein the interleaving is based on an identity matrix.

92. The method of claim 59, wherein the interleaving is based on a definition of 0, ceil (O) _s /2)、1、1+ceil(O _s The sequence of the timing indexes of (2), \8230, wherein O _s Is the number of occasions of said single search space in a time slot.

93. The method of claim 59, wherein the interleaving is based on definitions of 0, O _s 、2、O _s -1, \8230 \ 8230, the sequence of timing indexes of wherein O _s Is the number of occasions of the single search space in a time slot.

94. The method of claim 59, wherein the subset of the third set of resources is selected sequentially from within a single set of search spaces and a single aggregation level, and wherein resources in each occasion are reordered at the single set of search spaces and the single aggregation level prior to sequential selection.

95. The method of claim 94, wherein the reordering comprises an ascending order of resource indices in each occasion.

96. The method of claim 94, wherein the reordering comprises interleaving of resource indices in each occasion.

97. The method of claim 96 wherein the interleaving is based on having two rows and

an interleaver matrix of columns, wherein>

98. The method of claim 96, wherein a cyclic shift of the interleaved output is performed prior to the sequential selection, and wherein the cyclic shift is based on a timing index.

99. According to claim 9The method of 6, wherein the interleaving is based on an interleaver matrix, wherein the resource indices

Is read column-wise from the interleaver matrix, wherein ∑ is @>

100. The method of claim 96, wherein the interleaving is based on an interleaver matrix, wherein resource indices

Is read column-wise from the interleaver matrix, wherein ∑ is @>

101. The method of claim 96, wherein the interleaving is defined based on

The ordering of the resource indices of (a) is, wherein->

102. The method of claim 96, wherein the interleaving is defined based on

The ordering of the indices of the resources of (c), wherein->

103. The method of claim 96, wherein the interleaving is defined based on

The ordering of the resource indices of (a) is, wherein->

104. The method of claim 96, wherein the interleaving is defined based on

The ordering of the resource indices of (a) is, wherein->

105. The method of claim 59, wherein the selection order is further based on

In an ascending order, wherein->

106. The method of claim 59, wherein the selection order is further based on

In descending order of, wherein->

107. The method of claim 59, wherein the selection order is further based on a decreasing order of the degree of overlap of the sub-resources of each of the selected resources.

108. The method of claim 59, wherein the selected resource from the third set of resources comprises a sub-resource that includes a minimal degree of overlap with sub-resources from one or more resources of the first set of resources.

109. The method of claim 108, wherein the aggregate level of the selected resource from the third set of resources is the same as the aggregate level of the one or more resources in the first set of resources that include the least degree of overlap.

110. The method of claim 59, further comprising:

determining a subset of resources from a third set of resources, wherein each of the subset of resources comprises a sub-resource that is furthest from sub-resources of one or more resources from the first set of resources, and wherein a pair of sub-resources is furthest apart when the separation between their corresponding frequency domain positions is greater than the separation of the other pair of sub-resources; and is

After the determination, the subset of resources is added to the first set of resources.

111. The method of claim 59, wherein priority values are assigned to one or more resources in the second set of resources, and wherein the selection order is based on an ascending, descending, or interleaved order of the priority values.

112. The method of claim 111, wherein the priority value is based on at least

And O _s Wherein->

Is the amount of resources under a single set of search spaces and a single aggregation level and in an opportunity, andwherein O is _s Is the number of occasions of the single set of search spaces in a time slot.

113. The method of claim 112, wherein the priority values of the first subset of the second set of resources are the same, and wherein the first set of resources are selected from the first subset of the second set of resources in descending order of aggregation level.

114. The method of claim 113, wherein the aggregation levels of the second subset of the second set of resources are the same, and wherein the first set of resources is selected from the second subset of the second set of resources in ascending order of the search space set identifier.

115. The method of claim 59, wherein starting symbol indices for different occasion indices of a set of search spaces are different from each other within the set of search spaces.

116. The method of claim 59, wherein the first set of resources corresponds to reserved physical control channel (PDCCH) candidates.

117. The method of claim 59, wherein a resource in the first set of resources corresponds to a reserved physical control channel (PDCCH) candidate, wherein each resource in the first set of resources comprises one or more sub-resources, and wherein the one or more sub-resources correspond to Control Channel Elements (CCEs).

118. The method of claim 59, wherein the wireless node is a base station, and wherein performing the communication operation comprises transmitting control information in one or more resources of a first set of resources.

119. The method of claim 59, wherein the wireless node is a user equipment, and wherein performing the communication operation comprises performing a detection in one or more resources of a first set of resources.

120. A wireless communication device comprising a processor, wherein the processor is configured to implement the method of any of claims 1-119.

121. A computer readable medium comprising computer readable program medium code stored thereon, which when executed by a processor, causes the processor to implement the method of any of claims 1 to 119.