NOTIFICATION OF DELIVERY OF A RRLP MULTILATERATION TIMING ADVANCE REQUEST MESSAGE TO A BASE STATION SUBSYSTEM (BSS)
20200037279 ยท 2020-01-30
Inventors
Cpc classification
H04W72/29
ELECTRICITY
H04W28/24
ELECTRICITY
H04W64/00
ELECTRICITY
H04W68/00
ELECTRICITY
H04W56/0045
ELECTRICITY
International classification
H04W64/00
ELECTRICITY
H04W28/24
ELECTRICITY
Abstract
The present disclosure describes various techniques for enabling a Serving GPRS Support Node (SGSN) to provide a Base Station System (BSS) with an indication that a Logical Link Control (LLC) Protocol Data Unit (PDU) sent to a given wireless device contains a Radio Resource Location services Protocol (RRLP) Multilateration Timing Advance Request message such that the BSS after transmitting the LLC PDU to the given wireless device may invoke Timing Advance estimation algorithms for reception of uplink Packet Associated Control Channel (PACCH) acknowledgement block(s) (e.g., Extended Coverage (EC)-PACCH acknowledgment block(s)) from the given wireless device.
Claims
1. A Serving GPRS Support Node (SGSN) configured to interact with a Base Station Subsystem (BSS), the SGSN comprising: a processor; and, a memory that stores processor-executable instructions, wherein the processor interfaces with the memory to execute the processor-executable instructions, whereby the SGSN is operable to: transmit, to the BSS, a BSS General Packet Radio Service (GPRS) Protocol (BSSGP) Down Link (DL)-UNITDATA Packet Data Unit (PDU) which includes a Logical Link Control (LLC) PDU intended for a target wireless device, wherein the LLC PDU includes a Radio Resource Location Services Protocol (RRLP) PDU, wherein the RRLP PDU further includes a RRLP Multilateration Timing Advance (MTA) Request Message, wherein the BSSGP DL-UNITDATA PDU further includes a flag which indicates to the BSS a need to acquire timing advance information.
2. The SGSN of claim 1, wherein the flag is a code point in an information element.
3. A method implemented in a Serving GPRS Support Node (SGSN) configured to interact with a Base Station Subsystem (BSS), the method comprising: transmitting, to the BSS, a BSS General Packet Radio Service (GPRS) Protocol (BSSGP) Down Link (DL)-UNITDATA Packet Data Unit (PDU) which includes a Logical Link Control (LLC) PDU intended for a target wireless device, wherein the LLC PDU includes a Radio Resource Location Services Protocol (RRLP) PDU, wherein the RRLP PDU further includes a RRLP Multilateration Timing Advance (MTA) Request Message, wherein the BSSGP DL-UNITDATA PDU further includes a flag which indicates to the BSS a need to acquire timing advance information.
4. The method of claim 3, wherein the flag is a code point in an information element.
5. A Base Station Subsystem (BSS) configured to interact with a Serving GPRS Support Node (SGSN) and a target wireless device, the BSS comprising: a processor; and, a memory that stores processor-executable instructions, wherein the processor interfaces with the memory to execute the processor-executable instructions, whereby the BSS is operable to: receive, from the SGSN, a BSS General Packet Radio Service (GPRS) Protocol (BSSGP) Down Link (DL)-UNITDATA Packet Data Unit (PDU) which includes a Logical Link Control (LLC) PDU intended for the target wireless device, wherein the LLC PDU includes a Radio Resource Location Services Protocol (RRLP) PDU, wherein the RRLP PDU further includes a RRLP Multilateration Timing Advance (MTA) Request message; transmit, to the target wireless device, the LLC PDU which includes the RRLP PDU, wherein the RRLP PDU further includes the RRLP MTA Request Message; receive a Packet Associated Control Channel (PACCH) acknowledgment from the target wireless device; and, acquire timing advance information associated with the PACCH acknowledgment, wherein the BSS is informed of a need to acquire the timing advance information by a flag within the BSSGP DL-UNITDATA PDU.
6. The BSS of claim 5, wherein the flag is a code point in an information element.
7. The BSS of claim 5, wherein the BSS is further operable to transmit, to a Serving Mobile Location Center (SMLC), a BSSMAP Connection Oriented Message which includes (i) the acquired timing advance information; and (ii) accuracy information associated with the target wireless device.
8. A method implemented in a Base Station Subsystem (BSS) configured to interact with a Serving GPRS Support Node (SGSN) and a target wireless device, the method comprising: receiving, from the SGSN, a BSS General Packet Radio Service (GPRS) Protocol (BSSGP) Down Link (DL)-UNITDATA Packet Data Unit (PDU) which includes a Logical Link Control (LLC) PDU intended for the target wireless device, wherein the LLC PDU includes a Radio Resource Location Services Protocol (RRLP) PDU, wherein the RRLP PDU further includes a RRLP Multilateration Timing Advance (MTA) Request message; transmitting, to the target wireless device, the LLC PDU which includes the RRLP PDU, wherein the RRLP PDU further includes the RRLP MTA Request Message; receiving a Packet Associated Control Channel (PACCH) acknowledgment from the target wireless device; and, acquiring timing advance information associated with the PACCH acknowledgment, wherein the BSS is informed of a need to acquire the timing advance information by a flag within the BSSGP DL-UNITDATA PDU.
9. The method of claim 8, wherein the flag is a code point in an information element.
10. The method of claim 8, further comprising transmitting, to a Serving Mobile Location Center (SMLC), a BSSMAP Connection Oriented Message which includes (i) the acquired timing advance information; and (ii) accuracy information associated with the target wireless device.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] A more complete understanding of the present disclosure may be obtained by reference to the following detailed description when taken in conjunction with the accompanying drawings:
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DETAILED DESCRIPTION
[0039] A discussion is provided first herein to describe an exemplary wireless communication network that includes a CN node (e.g., SGSN, MME), multiple RAN nodes (e.g., BSSs, NodeBs, eNodeBs), and multiple wireless devices (e.g., mobile stations, IoT devices) in accordance with an embodiment of the present disclosure (see
Exemplary Wireless Communication Network 300
[0040] Referring to
[0041] The wireless communication network 300 includes the RAN nodes 302.sub.1 and 302.sub.2 (wireless access nodesonly two shown) which provide network access to the wireless devices 304.sub.1, 304.sub.2, 304.sub.3 . . . 304.sub.n. In this example, the RAN node 302.sub.1 is providing network access to wireless device 304.sub.1 while the RAN node 302.sub.2 is providing network access to wireless devices 304.sub.2, 304.sub.3 . . . 304.sub.n. The RAN nodes 302.sub.1 and 302.sub.2 are connected to the core network 306 (e.g., SGSN core network 306) and, in particular, to the CN node 307 (e.g., SGSN 307). The core network 306 is connected to an external packet data network (PDN) 308, such as the Internet, and a server 310 (only one shown). The wireless devices 304.sub.1, 304.sub.2, 304.sub.3 . . . 304n may communicate with one or more servers 309 (only one shown) connected to the core network 306 and/or the PDN 308. In this example, the RAN node 302.sub.2 and the CN node 307 are both connected to a positioning server 311 (e.g., Serving Mobile Location Center 311). The other RAN node 302.sub.2 can be connected to the same positioning server 311 (e.g., Serving Mobile Location Center 311) or to a different positioning server 311 (e.g., Serving Mobile Location Center 311).
[0042] The wireless devices 304.sub.1, 304.sub.2, 304.sub.3 . . . 304.sub.n may refer generally to an end terminal (user) that attaches to the wireless communication network 300, and may refer to either a MTC device (e.g., a smart meter) or a non-MTC device. Further, the term wireless device is generally intended to be synonymous with the term mobile device, mobile station (MS). User Equipment, or UE, as that term is used by 3GPP, and includes standalone wireless devices, such as terminals, cell phones, smart phones, tablets, cellular IoT devices, IoT devices, and wireless-equipped personal digital assistants, as well as wireless cards or modules that are designed for attachment to or insertion into another electronic device, such as a personal computer, electrical meter, etc.
[0043] Likewise, unless the context clearly indicates otherwise, the term RAN node 302.sub.1 and 302.sub.2 (wireless access node 302.sub.1 and 302.sub.2) is used herein in the most general sense to refer to a base station subsystem (BSS), a wireless access node, or a wireless access point in a wireless communication network 300, and may refer to RAN nodes 302.sub.1 and 302.sub.2 that are controlled by a physically distinct radio network controller as well as to more autonomous access points, such as the so-called evolved Node Bs (eNodeBs) in Long-Term Evolution (LTE) networks.
[0044] Each wireless device 304.sub.1, 304.sub.2, 304.sub.3 . . . 304.sub.n may include a transceiver circuit 310.sub.1, 310.sub.2, 310.sub.3 . . . 310n for communicating with the RAN nodes 302.sub.1 and 302.sub.2, and a processing circuit 312.sub.1, 312.sub.2, 312.sub.3 . . . 312.sub.n for processing signals transmitted from and received by the transceiver circuit 310.sub.1, 310.sub.2, 310.sub.3 . . . 310.sub.n and for controlling the operation of the corresponding wireless device 304.sub.1, 304.sub.2, 304.sub.3 . . . 304.sub.n. The transceiver circuit 310.sub.1, 310.sub.2, 310.sub.3 . . . 310.sub.n may include a transmitter 314.sub.1, 314.sub.2, 314.sub.3 . . . 314.sub.n and a receiver 316.sub.1, 316.sub.2, 316.sub.3 . . . 316.sub.n, which may operate according to any standard, e.g., the GSM/EDGE standard. The processing circuit 312.sub.1, 312.sub.2, 312.sub.3 . . . 312.sub.n may include a processor 318.sub.1, 318.sub.2, 318.sub.3 . . . 318.sub.n and a memory 320.sub.1, 320.sub.2, 320.sub.3 . . . 320.sub.n for storing program code for controlling the operation of the corresponding wireless device 304.sub.1, 304.sub.2, 304.sub.3 . . . 304.sub.n. The program code may include code for performing the procedures as described hereinafter.
[0045] Each RAN node 302.sub.1 and 302.sub.2 (BSS 302.sub.1 and 302.sub.2) may include a transceiver circuit 322.sub.1 and 322.sub.2 for communicating with wireless devices 304.sub.1, 304.sub.2, 304.sub.3 . . . 304.sub.n, a processing circuit 324.sub.1 and 324.sub.2 for processing signals transmitted from and received by the transceiver circuit 322.sub.1 and 322.sub.2 and for controlling the operation of the corresponding RAN node 302.sub.1 and 302.sub.2, and a network interface 326.sub.1 and 326.sub.2 for communicating with the core network 306. The transceiver circuit 322.sub.1 and 322.sub.2 may include a transmitter 328.sub.1 and 328.sub.2 and a receiver 330.sub.1 and 330.sub.2, which may operate according to any standard, e.g., the GSM/EDGE standard. The processing circuit 324.sub.1 and 324.sub.2 may include a processor 332.sub.1 and 332.sub.2, and a memory 334.sub.1 and 334.sub.2 for storing program code for controlling the operation of the corresponding RAN node 302.sub.1 and 302.sub.2. The program code may include code for performing the procedures as described hereinafter.
[0046] The CN node 307 (e.g., SGSN 307, MME 307) may include a transceiver circuit 336 for communicating with the RAN nodes 302.sub.1 and 302.sub.2, a processing circuit 338 for processing signals transmitted from and received by the transceiver circuit 336 and for controlling the operation of the CN node 307, and a network interface 340 for communicating with the RAN nodes 302.sub.1 and 302.sub.2. The transceiver circuit 336 may include a transmitter 342 and a receiver 344, which may operate according to any standard, e.g., the GSM/EDGE standard. The processing circuit 338 may include a processor 346 and a memory 348 for storing program code for controlling the operation of the CN node 307. The program code may include code for performing the procedures as described hereinafter.
Techniques for Enabling the RAN Node 302.SUB.2 .(for Example) to Estimate a Timing Advance Value
[0047] As discussed in the Background Section, at the 3GPP TSG-RANG Meeting #3 it had been proposed (but no solutions presented) that in
[0048] The problem with the prior art process can be seen with reference to
[0049] In the present disclosure with reference to
[0052] The BSS 302.sub.2 upon reception of the enhanced BSSGP DL-UNITDATA PDU 410 containing the new flag 420 can estimate the serving cell's Timing Advance by invoking advanced Timing Advance estimation algorithms such as oversampling and interpolation on the one or more PACCH Packet Downlink Acks 422 ((EC-)PACCH Packet Downlink Acks 422) received from the wireless device 304.sub.3 after sending the wireless device 304.sub.3 the LLC PDU 406 (containing the RRLP PDU 402 which contains the RRLP MTA Request message 404) using a downlink Temporary Block Flow (TBF) (EC-TBF)(see
[0053] In one embodiment, to ensure that the BSS 302.sub.2 is aware that the BSSGP DL-UNITDATA PDU 410 contains a RRLP PDU 402 (which contains a RRLP Multilateration Timing Advance Request message 404) inside an LLC PDU 406, it has been proposed to add the aforementioned new information element 420a referred to herein as the Message Indicator IE 420a to the BSSGP DL-UNITDATA PDU 410.
[0054] The SGSN 307 needs to know that the target wireless device 304.sub.3 is being requested to perform a MTA positioning procedure before the SGSN 307 is able to generate and transmit the BSSGP DL-UNITDATA PDU 410 which includes (i) the LLC PDU 406 (which includes the RRLP PDU 402 which includes the RRLP MTA Request message 404), and (ii) the flag 420 which indicates to the BSS 302.sub.2 that it needs to estimate TA information 413 when receiving a PACCH acknowledgment 422 from the target wireless device 304.sub.3 (see
[0055] In a first technique, to ensure that the SGSN 307 is aware that a RRLP MTA Request message 404 is being sent to a given wireless device 304.sub.3 (for example), the BSSGP POSITION-COMMAND PDU 400 sent by the BSS 302.sub.2 to the SGSN 307 is enhanced with a new Multilateration Timer IE 520 that provides the SGSN 307 with an indication 522 that the BSSGP POSITION-COMMAND PDU 400 is associated with a given wireless device 304.sub.3 (for example) that is going perform the MTA procedure. In its simplest form the new Multilateration Timer IE 520 may have an indication 522 which is a single bit flag. In addition, this indication 522 can trigger the SGSN 307 to start a timer 508 (e.g., MTA timer 508). In exemplary applications, the MTA timer 508 can be used by the SGSN 307 to (a) suspend downlink data delivery to the wireless device 304.sub.3 while the wireless device 304.sub.3 is performing the MTA procedure (b) guard against the SGSN 307 being asked to start another MTA positioning procedure with the wireless device 304.sub.3 (for example) by sending a paging message to the wireless device 304.sub.3 while the wireless device 304.sub.3 already has an ongoing MTA positioning procedure, and (c) allow the SGSN 307 to know the maximum time that it should allow for the MTA positioning procedure to be completed by the wireless device 304.sub.3.
[0056] In a second technique, to ensure that the SGSN 307 is aware that a RRLP MTA Request message 404 is being sent to a given wireless device 304.sub.3 (for example), the BSSGP POSITION-COMMAND PDU 400 sent by the BSS 302.sub.2 to the SGSN 307 is enhanced with a new Multilateration Timer IE 520 that not only indicates to the SGSN 307 that the BSSGP POSITION-COMMAND PDU 400 is associated with a given wireless device 304.sub.3 (for example) that is going perform the MTA procedure but also provides the SGSN 307 with a timer value 509 (e.g., MPM timer value 509) which is used to set the MTA timer 508. In exemplary applications, the MTA timer 508 can be used by the SGSN 307 to (a) suspend downlink data delivery to the wireless device 304.sub.3 while the wireless device 304.sub.3 is performing the MTA procedure (b) guard against the SGSN 307 being asked to start another MTA positioning procedure with the wireless device 304.sub.3 (for example) by sending a paging message to the wireless device 304.sub.3 while the wireless device 304.sub.3 already has an ongoing MTA positioning procedure, and (c) allow the SGSN 307 to know the maximum time that it should allow for the MTA positioning procedure to be completed by the wireless device 304.sub.3. The timer value 509 which is provided in the new Multilateration Timer IE 520 to the SGSN 307 is the same timer value which is associated with a Multilateration Positioning Method (MPM) timer 530 that the SMLC 311 transmits in a BSSMAP-LE CONNECTION ORIENTED INFORMATION message 504 (see
[0057] In a third technique, to ensure that the SGSN 307 is aware that a RRLP MTA Request message 404 is being sent to a given wireless device 304.sub.3 (for example), the BSSGP POSITION-COMMAND PDU 400 sent by the BSS 302.sub.2 to the SGSN 307 is enhanced where a RRLP Flags IE 535 is modified to not only indicate to the SGSN 307 that the BSSGP POSITION-COMMAND PDU 400 is associated with a given wireless device 304.sub.3 (for example) that is going perform the MTA procedure but also provides the SGSN 307 with a timer value 509 which is used to set the MTA timer 508. The timer value 509 which is provided in the RRLP Flags IE 535 to the SGSN 307 is the same timer value 509 which is associated with a Multilateration Positioning Method (MPM) timer 530 that the SMLC 311 provides in the BSSMAP-LE CONNECTION ORIENTED INFORMATION message 504 (see
[0058] The modified BSSGP POSITION-COMMAND PDU 400 and the aforementioned three techniques are also described in the co-filed U.S. patent application Ser. No. 15/886,616 entitled Notification of Ongoing Multilateration Timing Advance (MTA) Procedure to a Serving GPRS Support Node (SGSN), which claims the benefit of priority to U.S. Provisional Application Ser. No. 62/453,843, filed on Feb. 2, 2017. The entire contents of each of these documents are hereby incorporated herein by reference for all purposes.
Basic Functionalities-Configurations of SGSN 307, the BSS 302.sub.2, and the Wireless Device 304.sub.3
[0059] Referring to
[0060] Referring to
[0061] As those skilled in the art will appreciate, the above-described modules 1202 and 1204 of the SGSN 307 may be implemented separately as suitable dedicated circuits. Further, the modules 1202 and 1204 can also be implemented using any number of dedicated circuits through functional combination or separation. In some embodiments, the modules 1202 and 1204 may be even combined in a single application specific integrated circuit (ASIC). As an alternative software-based implementation, the SGSN 307 may comprise a memory 348, a processor 346 (including but not limited to a microprocessor, a microcontroller or a Digital Signal Processor (DSP), etc.) and a transceiver 336. The memory 348 stores machine-readable program code executable by the processor 346 to cause the SGSN 307 to perform the steps of the above-described method 1100.
[0062] Referring to
[0063] Referring to
[0064] As those skilled in the art will appreciate, the above-described modules 1402, 1404, 1406, 1408, 1410, and 1412 may be implemented separately as suitable dedicated circuits. Further, the modules 1402, 1404, 1406, 1408, 1410, and 1412 can also be implemented using any number of dedicated circuits through functional combination or separation. In some embodiments, the modules 1402, 1404, 1406, 1408, 1410, and 1412 may be even combined in a single application specific integrated circuit (ASIC). As an alternative software-based implementation, the BSS 302.sub.2 may comprise a memory 334.sub.2, a processor 332.sub.1 (including but not limited to a microprocessor, a microcontroller or a Digital Signal Processor (DSP), etc.) and a transceiver 322.sub.2. The memory 334.sub.2 stores machine-readable program code executable by the processor 332.sub.2 to cause the BSS 302.sub.2 to perform the steps of the above-described method 1300.
[0065] Referring to
[0066] Referring to
[0067] As those skilled in the art will appreciate, the above-described modules 1602 and 1604 of the wireless device 304.sub.3 may be implemented separately as suitable dedicated circuits. Further, the modules 1602 and 1604 can also be implemented using any number of dedicated circuits through functional combination or separation. In some embodiments, the modules 1602 and 1604 may be even combined in a single application specific integrated circuit (ASIC). As an alternative software-based implementation, the wireless device 304.sub.3 may comprise a memory 320.sub.3, a processor 318.sub.3 (including but not limited to a microprocessor, a microcontroller or a Digital Signal Processor (DSP), etc.) and a transceiver 310.sub.3. The memory 320.sub.3 stores machine-readable program code executable by the processor 318.sub.3 to cause the wireless device 304.sub.3 to perform the steps of the above-described method 1500.
[0068] In view of the foregoing, it will be appreciated by those skilled in the art that an objective of the present disclosure is to enable the SGSN 307 to provide the BSS 302.sub.2 (for example) with an indication, e.g., in the form of a flag 420, that the LLC PDU 406 sent to a given wireless device 304.sub.3 (for example) contains a RRLP Multilateration Timing Advance Request message 404 such that the BSS 302.sub.2 may invoke more advanced Timing Advance estimation algorithms for reception of the subsequent uplink (EC-) PACCH acknowledgment block(s) 422 received from the wireless device 304.sub.3. Recall: the BSS 302.sub.2 sends the wireless device 304.sub.3 an EC Downlink Assignment message to establish a downlink TBF which is then used to deliver the LLC PDU 406 to the wireless device 304.sub.3. When the EC Downlink Assignment message includes the Multilateration Information Request IE (see section 9.1.64 of 3GPP TS 44.018 v14.0.0 dated Dec. 23, 2016-12-23the contents of which are incorporated herein by reference for all purposes), it serves to inform the wireless device 304.sub.3 that it is to include MS Transmission Offset and MS Sync Accuracy information in the one or more PACCH acknowledgments 422 that the wireless device 304.sub.3 sends in response to receiving the LLC PDU 406, i.e., even though the BSS 302.sub.2 is informed of a need to estimate the timing advance information using advanced procedures by the flag 420 within the BSSGP DL-UNITDATA PDU 410 per
[0071] It should be appreciated that in the above described embodiments that these embodiments are exemplary and not mutually exclusive. For example, components from one embodiment may be tacitly assumed to be present in another embodiment and it will be obvious to a person skilled in the art how those components may be used in the other exemplary embodiments.
[0072] The exemplary embodiments described herein have been exemplified with Global System for Mobile telephony (GSM)/Enhanced Data rates for GSM Evolution (EDGE) as the communications network 300. The core network node 307 has been exemplified herein as being a Serving GPRS Support Node (SGSN) 307, but generally the core network node 307 may be any type of core network node that is serving the wireless device as well. For example, for NB-IoT the applicable core network node 307 may also be a Mobility Management Entity (MME). The radio access network node 302.sub.2 (controller node 302.sub.2) has been exemplified herein as being a BSS 302.sub.2 but generally the radio access network node 302.sub.2 may be any type of radio access network node 302.sub.2 that is serving the wireless device as well. The positioning node 311 has been exemplified herein as being a SMLC node 311 but may, e.g., for NB-IoT be an Evolved Serving Mobile Location Center (E-SMLC) node 311.
[0073] It should further be noted that, to anyone skilled in the art, there are several realizations of the embodiments described herein with principally equivalent functionality where e.g., introduced fields may be longer or shorter or coded in a different way. In addition, it should be noted that message names, parameters, and information elements may change during the course of the specification work, which implies the e.g., message names such as RRLP MULTILATERATION REQUEST message and RRLP Positioning Multilateration Timing Advance message shall be considered to be equivalent. This principle also applies to other messages, parameters, and information element names used herein so long as the principal use/function remain the same.
[0074] Those skilled in the art will appreciate that the use of the term exemplary is used herein to mean illustrative, or serving as an example, and is not intended to imply that a particular embodiment is preferred over another or that a particular feature is essential. Likewise, the terms first and second, and similar terms, are used simply to distinguish one particular instance of an item or feature from another, and do not indicate a particular order or arrangement, unless the context clearly indicates otherwise. Further, the term step, as used herein, is meant to be synonymous with operation or action. Any description herein of a sequence of steps does not imply that these operations must be carried out in a particular order, or even that these operations are carried out in any order at all, unless the context or the details of the described operation clearly indicates otherwise.
[0075] Of course, the present disclosure may be carried out in other specific ways than those herein set forth without departing from the scope and essential characteristics of the invention. One or more of the specific processes discussed above may be carried out in a cellular phone or other communications transceiver comprising one or more appropriately configured processing circuits, which may in some embodiments be embodied in one or more application-specific integrated circuits (ASICs). In some embodiments, these processing circuits may comprise one or more microprocessors, microcontrollers, and/or digital signal processors programmed with appropriate software and/or firmware to carry out one or more of the operations described above, or variants thereof. In some embodiments, these processing circuits may comprise customized hardware to carry out one or more of the functions described above. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.
[0076] Although multiple embodiments of the present disclosure have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it should be understood that the invention is not limited to the disclosed embodiments, but instead is also capable of numerous rearrangements, modifications and substitutions without departing from the present disclosure that as has been set forth and defined within the following claims.