Not applicable.
1. Field of the Invention
The present invention relates to a central control apparatus, a signal transmission apparatus and a signal forwarding apparatus for use in a multi-hop wireless network. More specifically, the present invention relates to a central control apparatus, a signal transmission apparatus and a signal forwarding apparatus for use in a multi-hop wireless network based on an IEEE 802.16 standard.
2. Descriptions of the Related Art
Wireless networks based on an IEEE 802.16e/j standard have the following evident disadvantages: the overhead of uplink (UL) control signals and the delay of transmission of control messages. Therefore, an IEEE 802.16m standard is developed to overcome those disadvantages.
Wireless networks based on the IEEE 802.16m standard (“802.16m network” for short) or LTE-Advanced are able to support high speed mobility and broadband access. Furthermore, the 802.16m or LTE-Advanced network may deploy relay stations (RSs) in the network architecture. The 802.16m or LTE-Advanced network should encounter numerous crucial issues, such as frequent handover, multi-hop relaying, synchronization, and so on. Relaying control signals from a base station (BS) to a mobile station (MS) via RSs and vice versa can be done straightforwardly in the 802.16m or LTE-Advanced networks; however they may not be done efficiently.
To explain more clearly, please refer to
Similarly, when the MS 15 intends to transmit a control signal 150 to the BS 11, it also has to transmit the control signal 150 to the RS 13 first. After receiving the control signal 150, the RS 13 generally decodes, demodulates or amplifies the control signal 150 to generate a control signal 132 comprising the content of the control signal 150, and forwards the control signal 132 to the MS 15. After receiving the control signal 132, the BS 11 may do some actions according to the content of the control signal 150. In other words, the control signal transmissions between the BS 11 and the MS 15 in the wireless network 1 based on the IEEE 802.16 are performed by the RS 13. If there are two or more RSs located in the transmission path of the control signal, the control signal must be relayed by the whole RSs located in the transmission path so that the control signal transmission must be delayed even though the control signal needs to be transmitted in real-time.
In summary, how to transmit the control signals of the 802.16/multi-hop wireless network effectively is still an objective for the industry to endeavor.
The primary objective of the present invention is to provide a central control apparatus for use in a multi-hop wireless network. The multi-hop wireless network includes at least one first station. The central control apparatus comprises a process module and a transceiver. The process module is configured to allocate a resource according to network resource information of the multi-hop wireless network and build a universal control (UC) channel between the central control apparatus and the at least one first station according to the allocated resource. The transceiver is configured to transmit a message about the UC channel to inform the at least one first station that the UC channel has been built so that the central control apparatus and the at least one first station may directly exchange at least one control signal through the UC channel, wherein each of the at least one first station may be considered as a signal transmission apparatus.
Another objective of the present invention is to provide a transmission method for use in the central control apparatus of the multi-hop wireless network. The multi-hop wireless network includes at least one first station. The central control apparatus stores network resource information of the multi-hop wireless network. The transmission method comprises the following steps of: allocating a resource according to the network resource information of the multi-hop wireless network; building a UC channel between the central control apparatus and the at least one first station according to the allocated resource; and transmitting a message about the UC channel to inform the least one first station that the UC channel has been built so that the central control apparatus and the at least one first station may directly exchange at least one control signal through the UC channel, wherein each of the at least one first station may he considered as a signal transmission apparatus.
Yet a further objective of the present invention is to provide a signal transmission apparatus for use in the multi-hop wireless network. The multi-hop wireless network includes a central control apparatus which is configured to build a UC channel between the signal transmission apparatus and the central control apparatus, and transmit a message about the UC channel. The signal transmission apparatus comprises a transceiver and a process module. The transceiver is configured to receive the message about the UC channel. The process module is configured to determine that the UC channel has been built between the signal transmission apparatus and the central control apparatus according to the message, and retrieve information, relating to the UC channel, from the message. The transceiver is further configured to directly exchange at least one control signal with the central control apparatus through the UC channel according to the information retrieved from the message.
Another objective of the present invention is to provide a transmission method for use in the signal transmission apparatus of the multi-hop wireless network. The multi-hop wireless network includes a central control apparatus. The central control apparatus is configured to build a UC channel between the signal transmission apparatus and the central control apparatus, and transmit a message about the UC channel. The transmission method comprises the following steps of: receiving the message about the UC channel; determining that the UC channel has been built between the signal transmission apparatus and the central control apparatus according to the message; retrieving information, relating to the UC channel, from the message; and exchanging at least one control signal with the central control apparatus through the UC channel according to the information retrieved from the message directly.
Yet a further objective of the present invention is to provide a signal forwarding apparatus for use in the multi-hop wireless network. The multi-hop wireless network includes a central control apparatus and a signal transmission apparatus. The central control apparatus is configured to build a UC channel between the central control apparatus, the signal transmission apparatus and the signal forwarding apparatus, and transmit a message about the UC channel. The signal transmission apparatus intends to transmit a first control signal to the central control apparatus. The signal forwarding apparatus comprises a transceiver and a process module. The transceiver is configured to receive the first control signal and the message about the UC channel. The process module is configured to determine that the UC channel has been built between the signal transmission apparatus and the central control apparatus according to the message, and retrieve information, relating to the UC channel, from the message. The transceiver is farther configured to transmit the first control signal to the central control apparatus through the UC channel according to the information retrieved from the message.
Another objective of the present invention is to provide a transmission method for use in the signal forwarding apparatus of the multi-hop wireless network. The multi-hop wireless network includes a central control apparatus and a signal transmission apparatus. The central control apparatus is configured to build a UC channel between the central control apparatus, the signal transmission apparatus and the signal forwarding apparatus, and transmit a message about the UC channel. The signal transmission apparatus intends to transmit a first control signal to the central control apparatus. The transmission method comprises the following steps of: receiving the first control signal; receiving the message about the UC channel; determining that the UC channel has been built between the signal transmission apparatus and the central control apparatus according to the message; retrieving information, relating to the UC channel, from the message; and transmitting the first control signal to the central control apparatus through the UC channel according to the information retrieved from the message.
According to the aforementioned descriptions, the present invention provides a UC channel built by the central control apparatus (may be a BS, an ASN gateway of the IEEE 802.16 standard) in the multi-hop wireless network. Through the UC channel, the signal transmission apparatus (may be an MS of the IEEE 802.16 standard), the signal forwarding apparatus (may be an RS of the IEEE 802.16 standard) and the central control apparatus may exchange the control signals with each others directly. Furthermore, the signal transmission apparatus may exchange the control signals with the central control apparatus via the signal forwarding apparatus through the UC channel. In other words, through the UC channel, the disadvantages of the conventional multi-hop wireless network can be overcome and the advantages thereof are also maintained.
The detailed technology and preferred embodiments implemented for the subject invention are described in the following paragraphs accompanying the appended drawings for people skilled in this field to well appreciate the features of the claimed invention.
In the following description, the present invention will be explained with reference to embodiments thereof. However, these embodiments are not intended to limit the present invention to any specific environment, applications or particular implementations described in these embodiments. Therefore, descriptions of these embodiments are only intended to illustrate rather than to limit the present invention. It should be appreciated that, in the following embodiments and the attached drawings, elements not related directly to the present invention are omitted from illustration; and dimensional relationships among individual elements in the attached drawings are illustrated only for ease of understanding, but not to limit the actual scale.
A first preferred embodiment of the present invention is illustrated in
The constructions of the central control apparatus 21, the signal forwarding apparatus 23 and the signal transmission apparatus 25 will be roughly introduced in
Please refer to
Basically, the UC channel can be presented by a frame structure. Please refer to
Please refer to
After building the UC channel, the process module 211 of the central control apparatus 21 generates an enable signal 218 to the transceiver 215. The transceiver 215 is configured to transmit a message 210 about the UC channel to inform the signal forwarding apparatus 23 and the signal transmission apparatus 25 that the UC channel has been built so that the central control apparatus 21, the signal forwarding apparatus 23 and the signal transmission apparatus 25 may directly exchange at least one control signal through the UC channel.
Please refer to FIG, 4 and
Similarly, the transceiver 251 of the signal transmission apparatus 25 is configured to receive the message 210 about the UC channel. The process module 253 of the signal transmission apparatus 25 is configure to determine that the UC channel has been built between the signal transmission apparatus 25, the signal forwarding apparatus 23 and the central control apparatus 21 according to the message 210, and retrieve information 252, relating to the UC channel, from the message 210. After that, the transceiver 251 of the signal transmission apparatus 25 may exchange at least one control signal with the central control apparatus 21 and the signal forwarding apparatus 23 according to the information 252 retrieved from the message 210.
Particularly, when the signal transmission apparatus 25 intends to transmit a first control signal 250 to the central control apparatus 21, as shown in
In another case, the transceiver 251 of the signal transmission apparatus 25 can transmit the first control signal 250 to the central control apparatus 21 via the signal forwarding apparatus 23 through the UC channel. Transmission delay of the first control signal 250 also can be reduced effectively because the signal forwarding apparatus 23 can forward the first control signal 250 to the central control apparatus 21 directly. In particular, the transceiver 231 of the signal forwarding apparatus 23 is configured to receive the first control signal 250, and transmit the first control signal 250 to the central control apparatus 21 through the UC channel according to the information 234 retrieved from the message 210.
When the central control apparatus 21 intends to transmit a second control signal 212 to the signal transmission apparatus 25, as shown in
In another case, the transceiver 215 of the central control apparatus 21 can transmit the second control signal 212 to the signal transmission apparatus 25 via the signal forwarding apparatus 23 through the UC channel. Transmission delay of the second control signal 212 also can be reduced effectively because the signal forwarding apparatus 23 can forward the second control signal 212 to the signal transmission apparatus 25 directly. In particular, the transceiver 231 of the signal forwarding apparatus 23 is configured to receive the second control signal 212, and transmit the second control signal 212 to the signal transmission apparatus 25 through the UC channel according to the information 234 retrieved from the message 210.
To manifest the effect of the UL channel, please refer to
In addition, the signal forwarding apparatus 23 also can exchange the control signals with the central control apparatus 21 or the signal transmission apparatus 25 through the UC channel. In
A second preferred embodiment of the present invention is illustrated in
The signal transmission apparatus moves from a location 53 to another location 54. The UC channels 501, 502, 503, 504, 505, 506 exist in the multi-hop wireless network 5. The central control apparatuses 51, 52 and the signal forwarding apparatus 55 can listen to the handover signals transmitted through the UC channels 501, 502, 503, 504, 505, 506, and cooperate in process of fast handover or route switching between signal transmission apparatus and the central control apparatuses 51, 52.
A third preferred embodiment of the present invention is illustrated in
The multi-hop wireless network 6 has the UC channel channels 601, 602, 603, 604, 605 which are built by the central control apparatus 61. The central control apparatus 61, the signal transmission apparatus 67, and the signal forwarding apparatus 63, 65 can listen to the control signals transmitted through the UC channels 601, 602, 603, 604, 605. In other words, the transmission apparatus 67 may transmit a control signal to the central control apparatus 61 through any combination of the UC channels 601, 602, 603, 604, 605.
A fourth preferred embodiment of the present invention is illustrated in
Step 703 is executed to build the UC channel between the central control apparatus, the at least one signal transmission apparatus and the at least one signal forwarding apparatus according to the allocated resource. Step 704 is executed to generate an enable signal. Finally, Step 705 is executed to transmit the message about the UC channel according to the enable signal to inform the least one signal transmission apparatus and the at least one signal forwarding apparatus that the UC channel has been built so that the at least one signal transmission apparatus may exchange the at least one control signal with the central control apparatus via the at least one signal forwarding apparatus through the UC channel.
In addition to the steps shown in
A fifth preferred embodiment of the present invention is illustrated in
Step 803 is executed to retrieve information, relating to the UC channel, from the message. Step 804 is executed to exchange at least one control signal with the central control apparatus through the UC channel according to the information retrieved from the message directly. Step 805 is executed to exchange the at least one control signal with the central control apparatus via the at least one signal forwarding apparatus through the UC channel according to the information retrieved from the message.
In addition to the steps shown in
A sixth preferred embodiment of the present invention is illustrated in
The transmission method of this embodiment comprises the following steps. Step 901 is executed to receive the first control signal. Step 902 is executed to receive the message about the UC channel. Step 903 is executed to determine that the UC channel has been built between the central control apparatus, the signal forwarding apparatus, the signal transmission apparatus and another signal forwarding apparatus according to the message. Step 904 is executed to retrieve information, relating to the UC channel, from the message. Step 905 is executed to transmit the first control signal to the central control apparatus through the UC channel according to the information retrieved from the message.
Step 906 is executed to transmit the first control signal to the central control apparatus via the another signal forwarding apparatus through the UC channel according to the information retrieved from the message. Step 907 is executed to receive the second control signal. Step 908 is executed to transmit the second control signal to the signal transmission apparatus through the UC channel according to the information retrieved from the message. Step 909 is executed to transmit the second control signal to the signal transmission apparatus via the another signal forwarding apparatus through the UC channel according to the information retrieved from the message. Step 910 is executed to transmit a third control signal to the central control apparatus through the UC channel according to the information retrieved from the message. Step 911 is executed to transmit a fourth control signal to the signal transmission apparatus through the UC channel according to the information retrieved from the message.
In addition to the steps shown in
According to the aforementioned descriptions, the present invention provides a UC channel built by the central control apparatus (may be a BS, an ASN gateway of the IEEE 802.16 standard) in the multi-hop wireless network. Through the UC channel, the signal transmission apparatus (may be an MS of the IEEE 802.16 standard) and the signal forwarding apparatus (may be an RS of the IEEE 802.16 standard), and the central control apparatus may exchange the control signals with each others directly. Furthermore, the signal transmission apparatus may exchange the control signals with the central control apparatus via the signal forwarding apparatus through the UC channel. In other words, through the UC channel, the disadvantages of the conventional multi-hop wireless network can be overcome and the advantages thereof are also maintained.
The above disclosure is related to the detailed technical contents and inventive features thereof. People skilled in this field may proceed with a variety of modifications and replacements based on the disclosures and suggestions of the invention as described without departing from the characteristics thereof Nevertheless, although such modifications and replacements are not fully disclosed in the above descriptions, they have substantially been covered in the following claims as appended.
This application claims the benefit of priority based on U.S. Ser. No. 61/021,380 filed on Jan. 16, 2008, the disclosures of which are incorporated herein by reference in their entirety.
Number | Date | Country | |
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61021380 | Jan 2008 | US |