U.S. patent application number 14/061142 was filed with the patent office on 2014-07-17 for signal reception apparatus, block decoding unit and method thereof in radio communication system.
This patent application is currently assigned to Samsung Electronics Co., Ltd.. The applicant listed for this patent is Samsung Electronics Co., Ltd.. Invention is credited to Deok-Hwan KIM, Seong-Wook SONG.
Application Number | 20140201605 14/061142 |
Document ID | / |
Family ID | 49585288 |
Filed Date | 2014-07-17 |
United States Patent
Application |
20140201605 |
Kind Code |
A1 |
KIM; Deok-Hwan ; et
al. |
July 17, 2014 |
SIGNAL RECEPTION APPARATUS, BLOCK DECODING UNIT AND METHOD THEREOF
IN RADIO COMMUNICATION SYSTEM
Abstract
A method for decoding a channel signal in a signal reception
apparatus is provided. The method includes performing a block
decoding operation on a channel signal block, and if the block
decoding for the channel signal block fails, re-performing a block
decoding operation on the channel signal block using a preset
pattern.
Inventors: |
KIM; Deok-Hwan; (Anseong-si,
KR) ; SONG; Seong-Wook; (Gwacheon-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Electronics Co., Ltd. |
Suwon-si |
|
KR |
|
|
Assignee: |
Samsung Electronics Co.,
Ltd.
Suwon-si
KR
|
Family ID: |
49585288 |
Appl. No.: |
14/061142 |
Filed: |
October 23, 2013 |
Current U.S.
Class: |
714/799 |
Current CPC
Class: |
H04L 1/0057 20130101;
H04L 1/0046 20130101; H03M 13/6356 20130101; H04L 1/0059 20130101;
G06F 11/08 20130101 |
Class at
Publication: |
714/799 |
International
Class: |
G06F 11/08 20060101
G06F011/08 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 16, 2013 |
KR |
10-2013-0004955 |
Claims
1. A method for decoding a channel signal in a signal reception
apparatus, the method comprising: performing a block decoding
operation on a channel signal block; and if the block decoding for
the channel signal block fails, re-performing a block decoding
operation on the channel signal block using a preset pattern.
2. The method of claim 1, wherein the re-performing of the block
decoding operation on the channel signal block using the preset
pattern comprises: changing a padding block except for an
information data block included in the channel signal block to a
reference padding block with a preset pattern; and re-performing a
block decoding operation on a channel signal block in which the
padding block is changed to the reference padding block.
3. The method of claim 1, wherein the re-performing of the block
decoding operation on the channel signal block using the preset
pattern comprises: detecting a length of an information data block
included in the channel signal block; and determining a remaining
part except for a part corresponding to the detected length in the
channel signal block as a padding block, and changing the
determined padding block to a reference padding block.
4. The method of claim 3, wherein the re-performing of the block
decoding operation on the channel signal block using the preset
pattern further comprises re-performing a block decoding operation
on a channel signal block in which the padding block is changed to
the reference padding block.
5. The method of claim 1, wherein the re-performing of the block
decoding operation on the channel signal block using the preset
pattern comprises: setting a length of an information data block
included in the channel signal block as an arbitrary length; and
determining a remaining part except for a part corresponding to the
set length in the channel signal block as a padding block, and
changing the determined padding block to a reference padding
block.
6. The method of claim 5, wherein the re-performing of the block
decoding operation on the channel signal block using the preset
pattern further comprises re-performing a block decoding operation
on a channel signal block in which the padding block is changed to
the reference padding block.
7. The method of claim 1, wherein the channel signal is a Paging
CHannel (PCH) signal.
8. A method for decoding a channel signal in a decoding unit of a
signal reception apparatus, the method comprising: performing a
block decoding operation on a channel signal block; and if the
block decoding for the channel signal block fails, re-performing a
block decoding operation on the channel signal block using a preset
pattern.
9. The method of claim 8, wherein the re-performing of the block
decoding operation on the channel signal block using the preset
pattern comprises: changing a padding block except for an
information data block included in the channel signal block to a
reference padding block with a preset pattern; and re-performing a
block decoding operation on a channel signal block in which the
padding block is changed to the reference padding block.
10. The method of claim 8, wherein the re-performing of the block
decoding operation on the channel signal block using the preset
pattern comprises: detecting a length of an information data block
included in the channel signal block; and determining a remaining
part except for a part corresponding to the detected length in the
channel signal block as a padding block, and changing the
determined padding block to a reference padding block.
11. The method of claim 10, wherein the re-performing of the block
decoding operation on the channel signal block using the preset
pattern further comprises re-performing a block decoding operation
on a channel signal block in which the padding block is changed to
the reference padding block.
12. The method of claim 8, wherein the re-performing of the block
decoding operation on the channel signal block using the preset
pattern comprises: setting a length of an information data block
included in the channel signal block as an arbitrary length; and
determining a remaining part except for a part corresponding to the
set length in the channel signal block as a padding block, and
changing the determined padding block to a reference padding
block.
13. The method of claim 12, wherein the re-performing of the block
decoding operation on the channel signal block using the preset
pattern further comprises re-performing a block decoding operation
on a channel signal block in which the padding block is changed to
the reference padding block.
14. The method of claim 8, wherein the channel signal is a Paging
CHannel (PCH) signal.
15. A signal reception apparatus comprising: a block decoding unit
for performing a block decoding operation on a channel signal
block, and if the block decoding for the channel signal block
fails, for re-performing a block decoding operation on the channel
signal block using a preset pattern.
16. The apparatus of claim 15, wherein the block decoding unit
changes a padding block except for an information data block
included in the channel signal block to a reference padding block
with a preset pattern, and re-performs a block decoding operation
on a channel signal block in which the padding block is changed to
the reference padding block.
17. The apparatus of claim 15, wherein the block decoding unit
detects a length of an information data block included in the
channel signal block, determines a remaining part except for a part
corresponding to the detected length in the channel signal block as
a padding block, and changes the determined padding block to a
reference padding block.
18. The apparatus of claim 17, wherein the block decoding unit
re-performs a block decoding operation on a channel signal block in
which the padding block is changed to the reference padding
block.
19. The apparatus of claim 15, wherein the block decoding unit sets
a length of an information data block included in the channel
signal block as an arbitrary length, determines a remaining part
except for a part corresponding to the set length in the channel
signal block as a padding block, and changes the determined padding
block to a reference padding block.
20. The apparatus of claim 19, wherein the block decoding unit
re-performs a block decoding operation on a channel signal block in
which the padding block is changed to the reference padding
block.
21. The apparatus of claim 15, wherein the channel signal is a
Paging CHannel (PCH) signal.
22. A block decoding unit in a signal reception apparatus, the
block decoding unit comprising: a block decoder for performing a
block decoding operation on a channel signal block, and if the
block decoding for the channel signal block fails, for
re-performing a block decoding operation on the channel signal
block using a preset pattern.
23. The block decoding unit of claim 22, further comprising: an
error correction controller for changing a padding block except for
an information data block included in the channel signal block to a
reference padding block with a preset pattern, wherein the block
decoder re-performs a block decoding operation on a channel signal
block in which the padding block is changed to the reference
padding block.
24. The block decoding unit of claim 22, further comprising: an
error correction controller for detecting a length of an
information data block included in the channel signal block, for
determining a remaining part except for a part corresponding to the
detected length in the channel signal block as a padding block, and
for changing the determined padding block to a reference padding
block.
25. The block decoding unit of claim 24, wherein the block decoder
re-performs a block decoding operation on a channel signal block in
which the padding block is changed to the reference padding
block.
26. The block decoding unit of claim 22, further comprising: an
error correction controller for setting a length of an information
data block included in the channel signal block as an arbitrary
length, for determining a remaining part except for a part
corresponding to the set length in the channel signal block as a
padding block, and for changing the determined padding block to a
reference padding block.
27. The block decoding unit of claim 26, wherein the block decoder
re-performs a block decoding operation on a channel signal block in
which the padding block is changed to the reference padding
block.
28. The block decoding unit of claim 22, wherein the channel signal
is a Paging CHannel (PCH) signal.
Description
PRIORITY
[0001] This application claims the benefit under 35 U.S.C.
.sctn.119(a) of a Korean patent application filed on Jan. 16, 2013
in the Korean Intellectual Property Office and assigned Serial No.
10-2013-0004955, the entire disclosure of which is hereby
incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a signal reception
apparatus, a block decoding unit and a method thereof in a radio
communication system. More particularly, the present invention
relates to a signal reception apparatus, a block decoding unit and
a method thereof in a radio communication system thereby enhancing
a block decoding performance for a channel signal block using a
preset pattern.
[0004] 2. Description of the Related Art
[0005] In a radio communication system of the related art, a Mobile
Station (MS) transits into a sleep mode in order to minimize power
consumption if the MS does not transmit/receive a data channel
signal to/from a Base Station (BS) during a preset time
interval.
[0006] The MS which has transited into the sleep mode may receive a
control channel signal during a preset listening interval. If the
MS's reception performance is less than a threshold reception
performance during the preset listening interval, the MS may not
properly receive the control channel signal, and detect important
control information included in the control channel signal.
[0007] If the control channel signal is a Paging CHannel (PCH)
signal and the MS's reception performance is less than the
threshold reception performance during the preset listening
interval, the MS may not receive the PCH signal. Accordingly, the
MS may not receive a call even though a calling party MS
continuously tries to call.
[0008] An example of the radio communication system is a Global
System for Mobile communications (GSM) communication system, and an
example of the control channel signal is the PCH signal. A PCH
signal transmission/reception processes in the GSM communication
system will be followed.
[0009] If paging information data targeting an MS occurs, a BS
generates a final PCH signal, i.e., a PCH data block by encoding
the paging information data using preset encoding schemes, e.g., a
block encoding scheme and a convolutional encoding scheme,
performing an interleaving operation on the encoded paging
information data using a preset interleaving scheme, and modulating
the interleaved paging information data using a preset modulation
scheme, e.g., a Gaussian filtered Minimum Shift Keying (GMSK)
scheme, and transmits the PCH data block to the MS. Since a size of
the paging information data is relatively small, the PCH data block
includes a preset pattern, e.g., a 0x2B padding block as well as
the paging information data, i.e., a paging information data
block.
[0010] The MS detects a final PCH data block by receiving a PCH
signal from the BS, de-modulating the PCH signal corresponding to
the modulation scheme used in the BS, i.e., the GMSK scheme,
de-interleaving the de-modulated PCH signal corresponding to the
interleaving scheme used in the BS, and decoding the de-interleaved
PCH signal using a Viterbi decoding scheme and a Fire decoding
scheme.
[0011] If the control channel signal, such as the PCH signal, is
not received ordinarily, serious performance degradation in a total
radio communication system may occur.
[0012] Therefore, there is a need for enhancing an error correction
performance and an error detection performance for the control
channel signal.
[0013] The above information is presented as background information
only to assist with an understanding of the present disclosure. No
determination has been made, and no assertion is made, as to
whether any of the above might be applicable as prior art with
regard to the present invention.
SUMMARY OF THE INVENTION
[0014] Aspects of the present invention are to address at least the
above-mentioned problems and/or disadvantages and to provide at
least the advantages described below. Accordingly, an aspect of the
present invention is to provide a signal reception apparatus, a
block decoding unit and a method thereof in a radio communication
system.
[0015] Another aspect of the present invention proposes a signal
reception apparatus, a block decoding unit and a method thereof in
a radio communication system thereby enhancing an error detection
performance.
[0016] Another aspect of the present invention proposes an
apparatus and a method for decoding a signal including a pattern
known between a signal transmission apparatus and a signal
reception apparatus in a radio communication system.
[0017] Another aspect of the present invention proposes an
apparatus and a method for decoding a signal by performing an
additional decoding operation using a pattern known between a
signal transmission apparatus and a signal reception apparatus in a
radio communication system thereby enhancing an error detection
performance.
[0018] In accordance with an aspect of the present invention, a
signal reception apparatus is provided. The apparatus includes a
block decoding unit for performing a block decoding operation on a
channel signal block, and if the block decoding for the channel
signal block fails, for re-performing a block decoding operation on
the channel signal block using a preset pattern.
[0019] In accordance with another aspect of the present invention,
a block decoding unit in a signal reception apparatus is provided.
The block decoding unit includes a block decoder for performing a
block decoding operation on a channel signal block, and if the
block decoding for the channel signal block fails, for
re-performing a block decoding operation on the channel signal
block using a preset pattern.
[0020] In accordance with another aspect of the present invention,
a method for decoding a channel signal in a signal reception
apparatus is provided. The method includes performing a block
decoding operation on a channel signal block, and if the block
decoding for the channel signal block fails, re-performing a block
decoding operation on the channel signal block using a preset
pattern.
[0021] In accordance with another aspect of the present invention,
a method for decoding a channel signal in a decoding unit of a
signal reception apparatus is provided. The method includes
performing a block decoding operation on a channel signal block,
and if the block decoding for the channel signal block fails,
re-performing a block decoding operation on the channel signal
block using a preset pattern.
[0022] Other aspects, advantages, and salient features of the
invention will become apparent to those skilled in the art from the
following detailed description, which, taken in conjunction with
the annexed drawings, discloses exemplary embodiments of the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The above and other aspects, features, and advantages of
certain exemplary embodiments of the present invention will be more
apparent from the following description taken in conjunction with
the accompanying drawings, in which:
[0024] FIG. 1 is a block diagram of an inner structure of a signal
reception apparatus in a radio communication system according to an
exemplary embodiment of the present invention;
[0025] FIG. 2 schematically illustrates an inner structure of a
block decoding unit according to an exemplary embodiment of the
present invention;
[0026] FIG. 3 is a flowchart illustrating a process of a block
decoding unit according to an exemplary embodiment of the present
invention;
[0027] FIG. 4 is a flowchart illustrating a process of a block
decoding unit according to an exemplary embodiment of the present
invention;
[0028] FIG. 5 is a performance gain graph of a block decoding in an
Additive White Gaussian Noise (AWGN) environment of a Global System
for Mobile communications (GSM) communication system according to
an exemplary embodiment of the present invention; and
[0029] FIG. 6 is a performance gain graph of a block decoding in a
channel environment of a GSM communication system according to an
exemplary embodiment of the present invention.
[0030] Throughout the drawings, it should be noted that like
reference numbers are used to depict the same or similar elements,
features, and structures.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0031] The following description with reference to the accompanying
drawings is provided to assist in a comprehensive understanding of
exemplary embodiments of the invention as defined by the claims and
their equivalents. It includes various specific details to assist
in that understanding but these are to be regarded as merely
exemplary. Accordingly, those of ordinary skill in the art will
recognize that various changes and modifications of the embodiments
described herein can be made without departing from the scope and
spirit of the invention. In addition, descriptions of well-known
functions and constructions may be omitted for clarity and
conciseness.
[0032] The terms and words used in the following description and
claims are not limited to the bibliographical meanings, but, are
merely used by the inventor to enable a clear and consistent
understanding of the invention. Accordingly, it should be apparent
to those skilled in the art that the following description of
exemplary embodiments of the present invention is provided for
illustration purpose only and not for the purpose of limiting the
invention as defined by the appended claims and their
equivalents.
[0033] It is to be understood that the singular forms "a," "an,"
and "the" include plural referents unless the context clearly
dictates otherwise. Thus, for example, reference to "a component
surface" includes reference to one or more of such surfaces.
[0034] By the term "substantially" it is meant that the recited
characteristic, parameter, or value need not be achieved exactly,
but that deviations or variations, including for example,
tolerances, measurement error, measurement accuracy limitations and
other factors known to those of skill in the art, may occur in
amounts that do not preclude the effect the characteristic was
intended to provide.
[0035] An exemplary embodiment of the present invention proposes a
signal reception apparatus, a block decoding unit and a method
thereof in a radio communication system.
[0036] An exemplary embodiment of the present invention proposes a
signal reception apparatus, a block decoding unit and a method
thereof in a radio communication system thereby enhancing a block
decoding performance for a channel signal block using a preset
pattern.
[0037] An exemplary embodiment of the present invention proposes a
signal reception apparatus, a block decoding unit and a method
thereof in a radio communication system thereby enhancing an error
detection performance.
[0038] An exemplary embodiment of the present invention proposes an
apparatus and a method for decoding a signal including a pattern
known between a signal transmission apparatus and a signal
reception apparatus in a radio communication system.
[0039] Exemplary embodiments of the present invention propose an
apparatus and a method for decoding a signal by performing an
additional decoding operation using a pattern known between a
signal transmission apparatus and a signal reception apparatus in a
radio communication system thereby enhancing an error detection
performance.
[0040] Exemplary embodiments of the present invention will be
described below with reference to a Global System for Mobile
communications (GSM) communication system. However, it will be
understood by those of ordinary skill in the art that exemplary
embodiments of the present invention may be applied to any one of a
Long-Term Evolution (LTE) mobile communication system, an
LTE-Advanced (LTE-A) mobile communication system, an Evolved Packet
System (EPS), an Institute of Electrical and Electronics Engineers
(IEEE) 802.16m mobile communication system, and the like.
[0041] For convenience, it will be assumed that the signal is a
Paging CHannel (PCH) signal. However, it will be understood by
those of ordinary skill in the art that exemplary embodiments of
the present invention may be applied to any one of all signals
including a padding block with a pattern which has been known
between a signal transmission apparatus and a signal reception
apparatus included in a related block.
[0042] For convenience, it will be assumed that a signal reception
apparatus proposed in exemplary embodiments of the present
invention is implemented in a Mobile Station (MS). However, it will
be understood by those of ordinary skill in the art that an entity
in which the signal reception apparatus is implemented is not
limited.
[0043] FIG. 1 schematically illustrates an inner structure of a
signal reception apparatus in a radio communication system
according to an exemplary embodiment of the present invention.
[0044] Referring to FIG. 1, the signal reception apparatus includes
a de-modulator 111, a de-interleaver 113, a convolutional decoder
115, and a block decoding unit 117.
[0045] A PCH signal received through an antenna, i.e., a PCH data
block, is input to the de-modulator 111, and the de-modulator 111
de-modulates the PCH data block based on a modulation scheme which
has been used in a modulator included in a signal transmission
apparatus, i.e., a Gaussian filtered Minimum Shift Keying (GMSK)
scheme, and outputs the de-modulated PCH data block to the
de-interleaver 113. The de-interleaver 113 de-interleaves the
de-modulated PCH data block based on an interleaving scheme which
has been used in an interleaver included in the signal transmission
apparatus, and outputs the de-interleaved PCH data block to the
convolutional decoder 115.
[0046] The convolutional decoder 115 performs an error correction
operation by performing a Viterbi decoding operation on the
de-interleaved PCH data block based on a convolutional encoding
scheme which has been used in a convolutional encoder included in
the signal transmission apparatus, and outputs the Viterbi decoded
PCH data block to the block decoding unit 117.
[0047] The block decoding unit 117 block decodes the Viterbi
decoded PCH data block based on a block encoding scheme which has
been used in a block encoder included in the signal transmission
apparatus. The block decoding unit 117 performs an additional error
correction operation as well as the error correction operation
performed in the convolutional decoder 115 until a preset criterion
is satisfied. Accordingly, if a block decoding is succeeded, the
block decoding unit 117 transfers a PCH data block which is
succeeded in the block decoding to an upper layer.
[0048] FIG. 2 schematically illustrates an inner structure of a
block decoding unit according to an exemplary embodiment of the
present invention.
[0049] Prior to the description of FIG. 2, a PCH signal received in
a signal reception apparatus will be described. First, it will be
assumed that paging information data includes 184 bits. According
to a block encoding for the paging information data with 184 bits,
40 parity bits and 4 tail bits are generated, so a block encoding
sequence with a total of 224 bits including the paging information
data with 184 bits, 40 parity bits and 4 tail bits is generated.
For example, a block encoding sequence with 224 bits is generated
as a coded bit sequence with 456 bits by performing a 1/2 code rate
convolutional encoding operation. The coded bit sequence with 456
bits is divided into a total of 4 bursts, each burst having 114
bits, and a burst with a total of 142 bits is generated by adding a
training sequence with 26 bits and 2 stealing flag bits to each of
4 bursts. The generated 4 bursts as a PCH signal are transmitted
through 4 GSM frames, respectively. A type of a PCH data block in a
GSM communication system according to an exemplary embodiment of
the present invention will be described with reference to Tables 1
to 3. A structure of the first type PCH data block in the GSM
communication system according to an exemplary embodiment of the
present invention is expressed in Table 1.
TABLE-US-00001 TABLE 1 Information element Type/Reference Presence
Format length L2 Pseudo Length L2 Pseudo Length M V 1 Radio
Resource (RR) Protocol M V 1/2 management Protocol Discriminator
Discriminator Skip Indicator Skip Indicator M V 1/2 Paging Request
Type 1 Message Type M V 1 Message Type Page Mode Page Mode M V 1/2
Channels Needed for Channel Needed M V 1/2 Mobiles 1 and 2 Mobile
Identity 1 Mobile Identity M LV 2-9 Mobile Identity 2 Mobile
Identity O TLV 3-10 P1 Rest Octets P1 Rest Octets M V 0-17
[0050] Prior to the description for Table 1, a PCH data block has
different types from the first to the third types according to the
number of PCH signals which a Base Station (BS) simultaneously
transmits to an MS. The first type PCH data block structure in
Table 1 represents a PCH data block structure used if the BS
transmits a PCH signal to a maximum of two MSs. As expressed in
Table 1, "Mobile Identity" fields are included in the first type
PCH data block. The number of "Mobile Identity" fields is equal to
the number of the PCH signals which the BS simultaneously
transmits. For example, the first type PCH data block includes a
total of two Mobile Identity fields, i.e., a Mobile Identity 1
field and a Mobile Identity 2 field, since a BS may simultaneously
transmit a maximum of two PCH signals.
[0051] In Table 1, an L2 Pseudo Length field indicates a length of
a paging information data block, a Radio Resource (RR) management
Protocol Discriminator field indicates an identification code of a
protocol processing a related message, a Skip Indicator field
indicates whether a related message may be omitted, a Paging
Request Type 1 Message Type field indicates a message type
identified in an upper layer protocol layer, a Page Mode field
indicates an operation mode of an MS included in a paging subgroup
which receives a paging message, a Channels Needed for Mobiles 1
and 2 field indicates a type of a logical channel for processing a
paging transaction, a P1 Rest Octets field indicates dummy bits for
padding a remaining part except for the fields, i.e., the L2 Pseudo
Length field, the RR management Protocol Discriminator field, the
Skip Indicator field, the Paging Request Type 1 Message Type field,
the Page Mode field, the Channels Needed for Mobiles 1 and 2 field,
the Mobile Identity 1 field, the Mobile Identity 2 field, and the
P1 Rest Octets field from the first type PCH data block.
[0052] A structure of the second type PCH data block in the GSM
communication system according to an exemplary embodiment of the
present invention is expressed in Table 2.
TABLE-US-00002 TABLE 2 Information element Type/Reference Presence
Format length L2 Pseudo Length L2 Pseudo Length M V 1 RR management
Protocol M V 1/2 Protocol Discriminator Discriminator Skip
Indicator Skip Indicator M V 1/2 Paging Request Type 2 Message Type
M V 1 Message Type Page Mode Page Mode M V 1/2 Channels Needed for
Channel Needed M V 1/2 Mobiles 1 and 2 Mobile Identity 1 Temporary
M V 4 Mobile Sub- scriber Iden- tity (TMSI)/ Packet domain TMSI
(P-TMSI) Mobile Identity 2 TMSI/P-TMSI M V 4 Mobile Identity 3
Mobile Identity O TLV 3-10 P2 Rest Octets P2 Rest Octets M V
1-11
[0053] The second type PCH data block structure in Table 2
represents a PCH data block structure used if the BS transmits a
PCH signal to a maximum of three MSs.
[0054] As expressed in Table 2, "Mobile Identity" fields are
included in the second type PCH data block. The number of "Mobile
Identity" fields is equal to the number of the PCH signals which
the BS simultaneously transmits. For example, the second type PCH
data block includes a total of three Mobile Identity fields, i.e.,
a Mobile Identity 1 field, a Mobile Identity 2 field, and a Mobile
Identity 3 field since the BS may simultaneously transmit a maximum
of three PCH signals.
[0055] In Table 2, an L2 Pseudo Length field indicates a length of
a paging information data block, an RR management Protocol
Discriminator field indicates an identification code of a protocol
processing a related message, a Skip Indicator field indicates
whether a related message may be omitted, a Paging Request Type 2
Message Type field indicates a message type identified in an upper
layer protocol layer, a Page Mode field indicates an operation mode
of an MS included in a paging subgroup which receives a paging
message, a Channels Needed for Mobiles 1 and 2 field indicates a
type of a logical channel for processing a paging transaction, a P2
Rest Octets field indicates dummy bits for padding a remaining part
except for the fields, i.e., the L2 Pseudo Length field, the RR
management Protocol Discriminator field, the Skip Indicator field,
the Paging Request Type 2 Message Type field, the Page Mode field,
the Channels Needed for Mobiles 1 and 2 field, the Mobile Identity
1 field, the Mobile Identity 2 field, the Mobile Identity 3 field,
and the P2 Rest Octets field from the second type PCH data
block.
[0056] A structure of the third type PCH data block in the GSM
communication system according to an exemplary embodiment of the
present invention is expressed in Table 3.
TABLE-US-00003 TABLE 3 Information element Type/Reference Presence
Format length L2 Pseudo Length L2 Pseudo Length M V 1 RR management
Protocol M V 1/2 Protocol Discriminator Discriminator Skip
Indicator Skip Indicator M V 1/2 Paging Request Type 3 Message Type
M V 1 Message Type Page Mode Page Mode M V 1/2 Channels Needed for
Channel Needed M V 1/2 Mobiles 1 and 2 Mobile Identity 1
TMSI/P-TMSI M V 4 Mobile Identity 2 TMSI/P-TMSI M V 4 Mobile
Identity 3 TMSI/P-TMSI M V 4 Mobile Identity 4 TMSI/P-TMSI M V 4 P3
Rest Octets P3 Rest Octets M V 3
[0057] The third type PCH data block structure in Table 3
represents a PCH data block structure used if the BS transmits a
PCH signal to a maximum of four MSs. As expressed in Table 3,
"Mobile Identity" fields are included in the third type PCH data
block. The number of "Mobile Identity" fields is equal to the
number of the PCH signals which the BS simultaneously transmits.
For example, the third type PCH data block includes a total of four
Mobile Identity fields, i.e., a Mobile Identity 1 field, a Mobile
Identity 2 field, a Mobile Identity 3 field, and a Mobile Identity
4 field since a BS may simultaneously transmit a maximum of four
PCH signals.
[0058] In Table 3, an L2 Pseudo Length field indicates a length of
a paging information data block, an RR management Protocol
Discriminator field indicates an identification code of a protocol
processing a related message, a Skip Indicator field indicates
whether a related message may be omitted, a Paging Request Type 3
Message Type field indicates a message type identified in an upper
layer protocol layer, a Page Mode field indicates an operation mode
of an MS included in a paging subgroup which receives a paging
message, a Channels Needed for Mobiles 1 and 2 field indicates a
type of a logical channel for processing a paging transaction, a P2
Rest Octets field indicates dummy bits for padding a remaining part
except for the fields, i.e., the L2 Pseudo Length field, the RR
management Protocol Discriminator field, the Skip Indicator field,
the Paging Request Type 3 Message Type field, the Page Mode field,
the Channels Needed for Mobiles 1 and 2 field, the Mobile Identity
1 field, the Mobile Identity 2 field, the Mobile Identity 3 field,
the Mobile Identity 4 field, and the P3 Rest Octets field from the
third type PCH data block.
[0059] As described above, a size of paging information data is
relatively small, so there is no data in a remaining part except
for a paging information data block in a PCH data block.
Accordingly, in a GSM communication system, a preset pattern, e.g.,
a padding block with 0x2B is included in a block except for the
paging information data block in the PCH data block. Here, a
padding block having a preset pattern will be called as a
"reference padding block".
[0060] Referring to FIG. 2, the block decoding unit 117 includes a
de-multiplexer 211, a block decoder 213, and an error correction
controller 215.
[0061] A PCH data block output from a convolutional decoder 115 is
input to the de-multiplexer 211. The de-multiplexer 211
de-multiplexes a PCH data block output from the error correction
controller 215 and a PCH data block output from the convolutional
decoder 115, and outputs the de-multiplexed signal to the block
decoder 213. The block decoder 213 decodes the signal output from
the de-multiplexer 211 and outputs the block decoded signal to the
error correction controller 215.
[0062] The error correction controller 215 determines whether the
PCH data block output from the block decoder 213 is succeeded for a
block decoding, and determines whether there is a need for
performing an additional block decoding on the PCH data block
output from the convolutional decoder 115 according to the
determined result. For example, the error correction controller 215
transfers the PCH data block to an upper layer if a block decoding
performed in the block decoder 213 has succeeded, whereas the error
correction controller 215 changes a padding block included in the
PCH data block to a reference padding block and performs an
additional block decoding on the reference padding block if the
block decoding performed in the block decoder 213 has failed.
[0063] While the de-multiplexer 211, the block decoder 213, and the
error correction controller 215 are shown in FIG. 2 as separate
units, it is to be understood that this is merely for convenience
of description. In other words, the de-multiplexer 211, the block
decoder 213, and the error correction controller 215 may be
incorporated into a single unit.
[0064] FIG. 3 is a flowchart illustrating a process of a block
decoding unit according to an exemplary embodiment of the present
invention.
[0065] Prior to the description of FIG. 3, an operation process of
a block decoding unit 117 as shown in FIG. 3 indicates an operation
process which the block decoding unit 117 performs in a case that
the block decoding unit 117 knows a length of paging information
data included in a paging data block beforehand.
[0066] Referring to FIG. 3, the block decoding unit 117 performs a
block decoding in step 311. The block decoding unit 117 determines
whether the block decoding has succeeded in step 313. If the block
decoding has succeeded, the block decoding unit 117 transfers a PCH
data block which has succeeded in the block decoding to an upper
layer in step 315.
[0067] If the block decoding has not succeeded, that is, if the
block decoding has failed, the block decoding unit 117 detects a
length of the PCH data block in step 317. The block decoding unit
117 changes a remaining padding block except for the paging
information data block from the PCH data block to a reference
padding block with a preset pattern in step 319. The block decoding
unit 117 re-performs a block decoding operation on the PCH data
block in which the remaining padding block has been changed to the
reference padding block in step 321. The block decoding unit 117
determines whether the block decoding has succeeded in step 323. If
the block decoding has succeeded, the block decoding unit 117
proceeds to step 315.
[0068] If the block decoding has not succeeded, that is, if the
block decoding has failed, the block decoding unit 117 transfers
only an error occurrence notification message indicating that the
PCH data block decoding has failed to the upper layer, and discards
the PCH data block without transferring the PCH data block to the
upper layer in step 325.
[0069] FIG. 4 is a flowchart illustrating a process of a block
decoding unit according to an exemplary embodiment of the present
invention.
[0070] Prior to the description of FIG. 4, an operation process of
a block decoding unit 117 as shown in FIG. 4 indicates an operation
process which the block decoding unit 117 performs in a case that
the block decoding unit 117 does not know a length of paging
information data included in a paging data block beforehand.
[0071] Referring to FIG. 4, the block decoding unit 117 performs a
block decoding in step 411. The block decoding unit 117 determines
whether the block decoding has succeeded in step 413. If the block
decoding has succeeded, the block decoding unit 117 transfers a PCH
data block which has succeeded in the block decoding to an upper
layer in step 415.
[0072] If the block decoding has not succeeded, that is, if the
block decoding has failed, the block decoding unit 117 sets a
length K of the paging information data block as a maximum paging
information data block length since the block decoding unit 117
does not know the length K of the paging information data block in
step 417. The block decoding unit 117 changes a remaining padding
block except for paging information data block corresponding to the
length K of the paging information data block to a reference
padding block with a preset pattern in step 419. The block decoding
unit 117 re-performs a block decoding operation on the PCH data
block in which the remaining padding block has been changed to the
reference padding block in step 421. The block decoding unit 117
determines whether the block decoding has succeeded in step 423. If
the block decoding has succeeded, the block decoding unit 117
proceeds to step 415.
[0073] If the block decoding has not succeeded, that is, if the
block decoding has failed, the block decoding unit 117 determines
whether the length K of the paging information data block is equal
to `1` in step 425. If the length K of the paging information data
block is not equal to `1`, the block decoding unit 117 decreases
the length K of the paging information data block by a preset
value, e.g., `1` (K=K-1) in step 427, and proceeds to step 417.
[0074] If the length K of the paging information data block is
equal to `1`, the block decoding unit 117 transfers only an error
occurrence notification message indicating that the PCH data block
decoding has failed to the upper layer, and discards the PCH data
block without transferring the PCH data block to the upper layer in
step 429.
[0075] FIG. 5 is a performance gain graph of a block decoding in an
Additive White Gaussian Noise (AWGN) environment of a GSM
communication system according to an exemplary embodiment of the
present invention.
[0076] Referring to FIG. 5, a horizontal axis denotes a Signal to
Noise Ratio (SNR), and a vertical axis denotes a Frame Error Rate
(FER). In FIG. 5, `Org` indicates a block decoding performance in a
case that a normal block decoding scheme is used, `Length=17`
indicates a block decoding performance in a case that the first
type PCH data block is used and a length of a padding block is 17
bytes according to an exemplary embodiment of the present
invention, and `Length=13` indicates a block decoding performance
in a case that a length of a padding block is 13 bytes according to
an exemplary embodiment of the present invention.
[0077] As shown in FIG. 5, if a length of a padding block is 17
bytes and an FER is 10%, an approximate 0.8[dB] performance gain is
acquired as compared with a block decoding scheme of the related
art. Moreover, an approximate 0.5[dB] performance gain is acquired
if a length of a padding block is 13 bytes as compared with the
block decoding scheme of the related art. As shown in FIG. 5, a
block decoding performance is described as changing an SNR in an
AWGN environment.
[0078] FIG. 6 is a performance gain graph of a block decoding in a
channel environment of a GSM communication system according to an
exemplary embodiment of the present invention.
[0079] Referring to FIG. 6, a horizontal axis denotes a Carrier to
Interference Ratio (CIR), and a vertical axis denotes an FER.
[0080] As shown in FIG. 6, a performance gain approximate 1.8[dB]
may be acquired if a length of a padding block is 17, and a
performance gain approximate 1.3[dB] may be acquired if a length of
a padding block is 13. As shown in FIG. 6, a block decoding
performance is described as changing a Co-Channel Interference
(CCI) in a Typical Urban, 50 km/hr (TU50) channel environment.
[0081] As is apparent from the foregoing description, exemplary
embodiments of the present invention enable an enhancement for an
error detection performance by performing an additional decoding
operation using a pattern known between a signal transmission
apparatus and a signal reception apparatus in a radio communication
system. Exemplary embodiments of the present invention enable an
enhancement for a signal decoding performance in a radio
communication system, so a total performance of the radio
communication system may be enhanced.
[0082] Exemplary embodiments of the present invention enable proper
reception of a signal in a radio communication system by enhancing
a decoding performance even though an MS's reception performance is
less than a threshold reception performance in a case that the MS
operates in an operation mode in which the MS performs a limited
signal reception operation, such as a sleep mode not a normal
mode.
[0083] While the invention has been shown and described with
reference to certain exemplary embodiments thereof, it will be
understood by those skilled in the art that various changes in form
and details may be made therein without departing from the spirit
and scope of the invention as defined by the appended claims and
their equivalents.
* * * * *