U.S. patent application number 17/463268 was filed with the patent office on 2022-07-21 for system and methods to reclaim unused throughput in an sdars system.
The applicant listed for this patent is Sirius XM Radio, Inc.. Invention is credited to John Goslin, Carl Scarpa, Edward Schell.
Application Number | 20220231754 17/463268 |
Document ID | / |
Family ID | |
Filed Date | 2022-07-21 |
United States Patent
Application |
20220231754 |
Kind Code |
A1 |
Schell; Edward ; et
al. |
July 21, 2022 |
SYSTEM AND METHODS TO RECLAIM UNUSED THROUGHPUT IN AN SDARS
SYSTEM
Abstract
Systems, algorithms and methods for reclaiming unused portions
of a satellite broadcast service's bandwidth for new services,
utilizing higher performance coding techniques to yield better
throughput, are presented. These systems, algorithms and methods
achieve the reclaimed bandwidth in a way that is invisible to a
legacy receiver, and that does not interfere with its reception of
a legacy signal. In one embodiment, new data may be transmitted
within a legacy transmission frame, for example within its cluster
structure, using the same modulation and synchronization as used
for the legacy data. The new data may be inserted into a channel or
other subdivision at a head end. In another embodiment, one or more
clusters or subdivisions with only new data may be transmitted,
using the same modulation and synchronization as the legacy data
clusters, but now employing a higher performing FEC and data
interleaving structure on those clusters which contain only new
data to yield an increase in available throughput. Finally, in a
third embodiment, one or more clusters containing only new data may
be transmitted, and in said one or more all new data clusters,
different modulation and synchronization may be used then that of
the legacy data clusters, thus employing a higher performing FEC
and data interleaving structure than that of the legacy clusters.
Various combinations of these approaches are also presented, as
well as a set of novel receivers, or receiver configurations, to
implement them and their combinations
Inventors: |
Schell; Edward; (Jackson,
NJ) ; Scarpa; Carl; (Plainsboro, NJ) ; Goslin;
John; (Burlington, NJ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Sirius XM Radio, Inc. |
New York |
NY |
US |
|
|
Appl. No.: |
17/463268 |
Filed: |
August 31, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16168285 |
Oct 23, 2018 |
11108460 |
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17463268 |
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14845080 |
Sep 3, 2015 |
10110296 |
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16168285 |
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62045385 |
Sep 3, 2014 |
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International
Class: |
H04B 7/185 20060101
H04B007/185; H04L 27/34 20060101 H04L027/34 |
Claims
1. A method of reclaiming unused legacy bandwidth in a broadcasting
system having a broadcast transmission frame with at least two
divisions, comprising: inserting new content data into at least one
transmission frame division, of at least one transmission frame, at
the head end, the at least one division also containing legacy
data; transmitting the at least one transmission frame division
using the same modulation and synchronization as the legacy data in
the transmission frame, wherein said inserting and transmitting are
performed such that a legacy receiver would not see the new data,
but receivers configured to decode the new content data would.
2. The method of claim 1, wherein the legacy transmission frame
data is modulated using both a primary and a secondary layer of
modulation, the new content data is modulated at the primary layer
of modulation, and the secondary layer of modulation operates on
both legacy content and the new content data;
3. The method of claim 1, further comprising sending information
describing either the new content data or channels where the new
content data may be accessed, in a manner that legacy receivers
receiving the transmission frame will not decode it.
4. The method of claim 1, further comprising sending extraction
information relative to the new content data within the at least
one transmission frame, only decodable by specially configured
receivers.
5. The method of claim 1, further comprising sending extraction
information relative to the new content data through one or more
out of band messaging schemes.
6. The method of claim 2, further comprising sending extraction
information relative to the new content data within the at least
one transmission frame, said extraction information arranged to
instruct a specially configured receiver how to separate the new
content data from other data in any division during decoding.
7. The method of claims 1-6, wherein any division containing both
new content data and legacy data is interleaved with other
divisions of the transmission frame.
8. The method of claim 7, wherein the transmission frame division
is one of a cluster, a cluster segment, a channel, or a physical
channel.
9. A method of reclaiming unused legacy bandwidth in a broadcasting
system having a broadcast transmission frame with at least two
divisions, comprising: inserting new content data into at least one
transmission frame division, of at least one transmission frame,
the at least one division only containing said new content data;
transmitting at least one additional transmission frame division
per transmission frame containing legacy data; transmitting any of
said transmission frame divisions containing only new content data
using the same modulation and synchronization as for legacy data,
but employing a higher performing FEC and data interleaving
structure so as to yield an increase in available throughput,
wherein said inserting and transmitting are performed such that a
legacy receiver would not see the divisions containing the new
content data, but receivers configured to decode the new content
data would.
10. The method of claim 9, wherein the legacy transmission frame
data is modulated using both a primary and a secondary layer of
modulation, the new content data in said new content data divisions
is modulated at the primary layer of modulation, and the secondary
layer of modulation operates on both divisions containing legacy
content and divisions containing only new content data.
11. The method of claim 9, further comprising additionally sending
new content data in one or more transmission frame divisions that
contain legacy data.
12. The method of claim 11, further comprising sending extraction
information relative to any new content data in any combined
division having both new content data and legacy data.
13. The method of claim 11, further comprising sending extraction
information relative to the new content data through one or more
out of band messaging schemes.
14. The method of claim 11, further comprising sending extraction
information relative to the new content data within the at least
one transmission frame, said extraction information arranged to
instruct a receiver how to separate the new content data from other
data during decoding.
15. The method of claim 9, wherein divisions containing solely new
content data are interleaved with other divisions containing wholly
or partially legacy data.
16. The method of claim 9, wherein the transmission frame division
is one of a cluster, a cluster segment, a channel, or a physical
channel.
17. The method of claim 9, wherein said higher performing FEC
includes one of Turbo or Low Density Parity Check codes, and
wherein said higher performing data interleaving structure includes
at least one of a programmable convolutional interleaver, or an
interleaver with significantly greater delay spreads over a fixed
duration of the legacy system.
18. A method of reclaiming unused legacy bandwidth in a
broadcasting system having a broadcast transmission frame with at
least two divisions, comprising: transmitting one or more
transmission frame divisions with only new content data;
transmitting one or more other transmission frame divisions that
contain legacy content data; wherein in said one or more
transmitted solely new content data divisions, different modulation
and synchronization schemes are used than those used on the other
transmission frame divisions that contain legacy content data, and
wherein said transmitting is performed such that a legacy receiver
would not see the divisions containing new data, but receivers
configured to decode the new content data would.
19. The method of claim 18, wherein the one or more transmission
frame divisions containing solely new content data are processed
using a higher performing FEC and data interleaving structure than
that of the other divisions that contain any legacy content
data.
20. The method of claim 18, wherein in addition to the divisions
containing solely new content data, transmitting additional new
data within at least one of the other transmission frame divisions
that contain legacy content data, using the same modulation and
synchronization as the legacy data divisions.
21. A system, comprising: a transmitter comprising a legacy
encoding module, a hierarchical modulation encoding module and a
multiplexer; and a receiver comprising a demodulator, a legacy
decoding module and a hierarchical modulation decoding module,
wherein the transmitter is configured to encode and transmit both
new content data and legacy content data that are combined in one
or more transmission frame divisions, and wherein the receiver is
configured to demodulate the data and then separate the new content
data from the legacy content data in the legacy decoder module
using received extraction information.
22. A system, comprising: a transmitter comprising a legacy
encoding module, a hierarchical modulation encoding module and a
multiplexer; and a receiver comprising a demodulator, a legacy
decoding module, a hierarchical modulation decoding module, and a
new data decoding module, wherein the transmitter is configured to
encode and transmit new content data and legacy content data, the
new content data sent in one or more transmission frame divisions
containing only new content data, and wherein the receiver is
configured to demodulate the data and then send the new content
data to the new content data decoder, and send the legacy content
data to the legacy decoder.
23. The system of claim 22, wherein the transmitter is further
configured to also encode and transmit combination divisions
containing both new content data and legacy content data.
24. The system of claim 23, wherein the transmitter is further
configured to send extraction information relative to any new
content data in any combination division.
25. The system of claim 23, further comprising sending extraction
information relative to the new content data through one or more
out of band messaging schemes.
26. The system of any of claims 23-25, wherein the receiver is
configured to demodulate the data in said combination divisions and
then, at the legacy decoder, separate the new content data from the
legacy content data using received extraction information.
27. The system of claim 22, wherein the transmitter is configured
to modulate all data in any division with a secondary modulation
layer containing hierarchical modulation content.
28. A system, comprising: a transmitter comprising a legacy
encoding module, a hierarchical modulation encoding module and a
multiplexer; and a receiver comprising a legacy demodulator, a new
data demodulator, a legacy decoding module, a hierarchical
modulation decoding module, and a new data decoding module, wherein
the transmitter is configured to encode and transmit new content
data and legacy content data, the new content data sent in one or
more transmission frame divisions containing only new content data,
and wherein the receiver is configured to: demodulate the legacy
content data divisions in a legacy demodulator and send the
demodulated data to a legacy decoder and a hierarchical modulation
decoder, and demodulate the new content data in a new data
demodulator, and send the demodulated new data divisions to the new
decoder.
29. The system of claim 28, wherein the only new content containing
divisions are modulated differently by the transmitter than the
other divisions containing legacy data.
30. The system of claim 29, wherein the only new content containing
divisions are modulated using include a combination of QPSK, 8PSK,
16QAM, C16QAM or other multi-symbol scheme.
31. The system of claim 29, wherein the only new content containing
divisions are not hierarchically modulated, but integrated as a
singly modulated division.
32. The system of claim 29, wherein the transmitter is further
configured to also encode and transmit combination divisions
containing both new content data and legacy content data.
33. The system of claim 32, wherein the transmitter is further
configured to send extraction information relative to any new
content data in any combination division.
34. The system of claim 32, wherein extraction information relative
to the new content data is sent through one or more in band or out
of band messaging schemes.
35. The system of any of claims 32-34, wherein the receiver is
configured to demodulate the data in said combination divisions and
then, at the legacy decoder, separate the new content data from the
legacy content data using received extraction information.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 16/168,285, filed Oct. 23, 2018, which is a
divisional of U.S. patent application Ser. No. 14/845,080, filed
Sep. 3, 2015, which claims the benefit of U.S. Provisional Patent
Application 62/045,385, filed on Sep. 3, 2014, the disclosure of
which is hereby incorporated by reference herein in its
entirety.
TECHNICAL FIELD
[0002] This invention relates to digital satellite radio
transmission, and in particular to methods of leveraging extra
bandwidth in legacy transmission schemes to send content and/or
data modulated and framed using newer techniques.
BACKGROUND OF THE INVENTION
[0003] The present invention seeks to improve the efficiency of
bandwidth usage in Satellite Digital Audio Radio Services
("SDARS"), such as those provided by Sirius XM Radio, Inc. ("SXM").
It is thus noted that during the initial design phase of legacy
SDARS systems, Concatenated Reed-Solomon Convolutional Codes were
considered state of the art in Forward Error Correction (FEC)
techniques. Since then, great advances have been made on iterative
decoding schemes with the introduction of Turbo and LDPC codes,
which are now the common practice in all new system designs and
standards, such as, for example, 3gpp2, LTE, 802.11, etc. Thus, for
example, SXM has taken advantage of these iterative codes by
deploying Hierarchical Modulation ("HM") systems on their legacy
systems, thereby achieving an increased throughput of at least 25%
over the original legacy design. Various SXM HM systems are
described in U.S. Pat. Nos. 8,184,743, 9,036,720 and the various
patent applications and references described therein, U.S. Pat. No.
8,139,689, and PCT/US2011/000143, now published as WO 2011/094001,
the disclosure of each of which is hereby incorporated herein by
reference in its entirety. While the addition of HM was a great
improvement as regards bandwidth efficiencies, the modulation and
FEC coding used (since the beginning) in the legacy systems still
present a major roadblock to any further advances in overall
bandwidth efficiency. Moreover, any changes made to a legacy system
would also need to maintain backwards compatibility with the
millions of existing satellite radios in the market.
[0004] What is needed in the art are ways to overcome these
problems to obtain additional bandwidth without sacrificing
backwards compatibility of existing receivers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 illustrates insertion, transmission and extraction of
new content data into an SDARS broadcast according to an exemplary
embodiment of the present invention;
[0006] FIG. 2 illustrates an exemplary cluster structure as used in
the Sirius Satellite Radio legacy system;
[0007] FIG. 3 illustrates an exemplary novel receiver to be used in
connection with an alternate exemplary embodiment of the present
invention; and
[0008] FIG. 4 illustrates a novel modulation approach with both a
legacy demodulator and a new signal demodulator, where the legacy
demodulator operates on both legacy content as well as new partial
cluster content, according to an exemplary embodiment of the
present invention.
SUMMARY OF THE INVENTION
[0009] Systems, algorithms and methods for reclaiming unused
portions of a satellite broadcast service's bandwidth for new
services, utilizing higher performance coding techniques to yield
better throughput, are presented. These systems, algorithms and
methods achieve the reclaimed bandwidth in a way that is invisible
to a legacy receiver, and that does not interfere with its
reception of a legacy signal. In one embodiment, new data may be
transmitted within a legacy transmission frame, for example within
its cluster structure, using the same modulation and
synchronization as used for the legacy data. The new data may be
inserted into a channel or other subdivision at a head end. In
another embodiment, one or more clusters or subdivisions with only
new data may be transmitted, using the same modulation and
synchronization as the legacy data clusters, but now employing a
higher performing FEC and data interleaving structure on those
clusters which contain only new data to yield an increase in
available throughput. Finally, in a third embodiment, one or more
clusters containing only new data may be transmitted, and in said
one or more all new data clusters, different modulation and
synchronization may be used then that of the legacy data clusters,
thus employing a higher performing FEC and data interleaving
structure than that of the legacy clusters. Various combinations of
these approaches are also presented, as well as a set of novel
receivers, or receiver configurations, to implement them and their
combinations.
DETAILED DESCRIPTION OF THE INVENTION
[0010] In exemplary embodiments of the present invention, unused
portions of a legacy SDARS broadcast bandwidth may be reclaimed and
used for new content/data services, utilizing higher performance
coding techniques to yield better throughput. It is noted that
while the systems and methods presented below are illustrated with
reference to the lower frequency Sirius SDARS band, this is for
purposes of illustration only, and the disclosed methods are
understood to not be limited thereto, or for that matter, to any
particular system or service. A similar approach may thus also be
applied to the upper frequency XM band, or any other satellite
radio service or similar context where bandwidth in a legacy system
may be reclaimed and used to transmit new content or data using
both more efficient (i) modulation techniques, and (ii) error
correction coding, than that used in the original legacy
system.
[0011] The elimination of redundancy in channel content, as well as
improvements in audio compression have been able to free up
portions of available throughput in legacy systems, such as, for
example, the SiriusXM SDARS "low band" (this is the "Sirius"
branded service). In the case of this band, since current
radios/receivers in production will still be receiving the same
comparable content as before (i.e., the "legacy signal"), there is
no need to make the newly liberated ("New") bandwidth available to
legacy radios. They currently receive all that they can. This state
of affairs also provides freedom on how the new throughput may be
utilized, for content that a legacy radio may not be capable of
processing. Thus, a goal or motivation of various exemplary
embodiments of the present invention is the ability to siphon off
unused legacy throughput (achieved due to such eliminations of
redundancy and improved audio compression) for new content and
services that are only made available to future radios, thus
allowing an SDARS provide to better monetize the streams and obtain
greater bandwidth efficiency from its spectrum.
[0012] In exemplary embodiments of the present invention, siphoning
off "New" bandwidth can be accomplished in multiple ways. These are
next described, with reference to three options
Option 1: Insertion of New Content into Existing Clusters
[0013] A first exemplary method is to utilize an entire legacy
delivery system. In this case, the "New" content can be inserted
into the Legacy baseband layer at the Head End system, where
current content is inserted. The content may be, for example,
divided and segmented into physical channels of varying size or
other useful divisions. The new content can, for example, occupy
one or more physical channels. However, no information about the
"New" content need be provided via the legacy channel mapping (as
legacy receivers cannot decode it), thus leaving legacy radios
unaware of the new content. The "New" content can go through the
same physical layer synchronization and FEC processing as the
legacy path does. Moreover, at the receiver, only new radio
platforms with knowledge of the "New" content will be able to
provide the necessary extraction information to receive the New
data. This contemplates more modern, and more advanced, receivers
being made available to the public that can decode the new content
inserted in the broadcast given the techniques of the present
invention, but said new content having no effect--and not being
"seen"--by older receivers, i.e. those designed to simply receive
the legacy transmission. Thus, the extraction information may be
directed only towards such capable receivers through various
messaging schemes. In some embodiments, the measured benefit of
this approach will generally be limited by the amount of throughput
made available through added efficiencies of the existing legacy
content, as described above.
[0014] FIG. 1 is a simplified drawing showing the insertion and
extraction of "New" content in exemplary embodiments of the present
invention according to this first option. With reference thereto,
at the transmitter side, a New Transmitter 100 is shown, where New
Content 111 is input to a Legacy Encoding Module 105, together with
standard Legacy Content 113. The New Transmitter 100 also has a HM
Encoding Module 110, whose operation and inputs remain unchanged by
any of the New data in this example. On the receiver side, a New
Receiver(1) 150 is shown. There is a single DEMOD 155 signal path,
because, in this example, the legacy demodulation scheme has not
changed, and the new data may simply be sent within that existing
modulation scheme inserted in one or more clusters. However, the
Legacy Decode Module 160 now outputs two datastreams. A New Content
171 datastream, coming from the New data 111 inserted into one (or
more than one) of the legacy clusters, and a regular Legacy Content
173 datastream, as in the standard legacy transmission. To
correctly extract the "New" Content 171, "New" Extraction
Information 170 may be accessed by the Legacy Decode Module 160,
which should be sent to the receiver, for example, in the same
fashion as the channel mapping.
[0015] As an illustrative example, the throughput of the Sirius
broadcast legacy system, for example, is evenly divided into five
individual groupings, called clusters. Each cluster is associated
with data for a number of channels, e.g. 20. Each of these clusters
is independent of the others and is transmitted in a time-sliced,
e.g., Time Division Multiplexing, approach. Each cluster is itself
divided into 255 subsections. These subsections are interleaved
with those of the remaining clusters, as shown in FIG. 2.
[0016] So, as shown in FIG. 2, taking, for example, Cluster 1 200,
its 255 subsections are interleaved with the 255 subsections of
Clusters 2, 3, 4 and 5 to generate a transmission frame. This
structure is described in detail in U.S. Pat. No. 6,618,367 which
is fully incorporated by reference herein. So, at a beginning
portion 210 of a transmission frame, a first subsection of Cluster
1, C1(1), is placed at the beginning of the transmission frame, as
shown by arrow 230. It is noted that in U.S. Pat. No. 6,618,367,
the subsections spoken of here are referred to as "Segments", but
can be any subdivision or division of a transmission frame
Similarly, following arrow 233, the second subsection of Cluster 1,
C1(2), is placed in the transmission frame after the remaining
first subsections of each of Clusters 2-5, namely C2(1), C3(1),
C4(1) and C5(1), have been placed. This process continues, where
all subsections N for a Cluster M are interleaved with the
corresponding subsections CN(M) of all clusters M, until the last
subsection, subsection 255 of Cluster 1, i.e. C1 (255) in FIG. 2,
is placed, as shown by arrow 235, and is then followed by
subsections C2(255), C3(255), C4(255) and C5(255) as shown at
220.
[0017] Thus, if the liberated throughput from the legacy
transmission is greater than or equal to the size of one cluster or
subdivision, an opportunity arises to improve on the overall
bandwidth efficiency by claiming one or more entire clusters to be
used in a new coding scheme. This is next described.
Option 2: Full Cluster Reclamation Using Legacy Synchronization and
Modulation
[0018] A second option thus involves reclaiming an entire cluster
for "New" content and services. This approach is to utilize the
same legacy synchronization and modulation, but now employ a higher
performing FEC and data interleaving structure to yield an increase
in available throughput. In this case, an entire cluster, or
multiple entire clusters, can be replaced with the newly encoded
content. As with the existing legacy scheme, the "New" cluster will
be similarly segmented and interleaved with the remaining clusters
using the same scheme as the legacy transmission. Such as, for
example, the scheme illustrated in U.S. Pat. No. 6,618,367, as
noted. Since there are no changes to the legacy synchronization and
modulation, there will be no impact on legacy radios. Any use of HM
will also be unaffected, as the New data will only be placed on the
legacy QPSK symbol mapping, leaving the mapping of the HM intact.
The choice of Forward Error Correction ("FEC") for the New Content
clusters can be, but is not limited to, Turbo or LDPC codes, for
example. The interleaver structure for said New clusters can be,
for example, a programmable convolutional interleaver, which is
capable of much greater delay spreads over the fixed duration of
the legacy system. As more than one entire cluster is freed up,
multiple instantiations of this technique can be used to reclaim
additional clusters until finally all five clusters have been
reclaimed and used for New content.
[0019] It is noted that this "reclamation of entire cluster"
approach may also be used in conjunction with the previously
mentioned approach of FIG. 1, where only a portion of a cluster is
reclaimed using the existing legacy coding scheme. Such a
combination provides interim increases in throughput, until full
clusters become available, at which time another instance of Option
2 would be implemented. In addition to the partial cluster
throughput, for the SXM Sirius band case, new FEC coding is
generally expected to provide as much as a 25% increase over the
current legacy cluster throughput, resulting in, for example, an
additional 200 Kbps per cluster.
[0020] FIG. 3 illustrates a simplified drawing of an exemplary
"New" receiver called "New Receiver (2)" 350 which may be used in a
combination of a "partial cluster" reclamation of throughput as per
Option 1 with a "full cluster" reclamation of throughput as per
Option 2. With reference thereto, signal enters at antenna 325 and
from there is a single DEMOD 355 signal path, because the legacy
demodulation scheme has not changed. However, a full "New" cluster
is decoded at the NEW Decode module 367, the HM data 375 is decoded
at HM Decode 365, as in a standard legacy receiver, and the Legacy
Decode module 360 outputs two datastreams, just as in the case of
FIG. 1. These include a New Partial Cluster Content 371 datastream,
coming from the New data inserted into one of the legacy clusters
as per Option 1, and a regular Legacy Content 373, as in the
standard legacy transmission. To correctly extract the "New"
Partial Cluster Content 371, "New" extraction information 370 is
accessed by the Legacy Decode module 360, as was also the case in
FIG. 1. Here, the novel aspect is that New Full Cluster Content 377
is extracted by New Decode module 367.
Option 3: Full Cluster Reclamation and Remodulation
[0021] In exemplary embodiments of the present invention, a third
option also involves the reclaiming of an entire cluster just as in
Option 2. However, in this third exemplary approach, a complete
re-modulation of the transmitted symbols for a given cluster is
also performed. In this scheme, both the original Legacy and the HM
coding can be replaced with a single, more efficient, coding scheme
for a New cluster. In exemplary embodiments, a first assumption
that may be made is that any HM system will also be clusterized in
similar fashion to the legacy path. Therefore, the HM system may be
designed in conjunction with this approach, alleviating any need
for backwards compatibility. The loss of throughput from removing a
cluster of HM data can be accounted for in the "New" integrated
(Legacy and HM) cluster. Thus in this option, full access to the
symbols during the cluster period is provided, allowing it to
deploy any sort of modulation, synchronization, and FEC most
appropriate. For example, synchronization symbols may be common,
but not limited to, the legacy synchronization patterns to minimize
impact to the legacy service. The modulation may include a
combination of, but again, is not limited to, QPSK, 8PSK, 16QAM,
C16QAM or other multi-symbol scheme. Any data dispersion (i.e.
interleaver, mixer, etc.) may be unique to the new system. Also,
for example, the FEC may be, but is not limited to, Turbo or LDPC
codes. The main advantage to the exemplary approach of this third
option is the added efficiency gained by combining the coding of
the older Legacy and HM datastreams into a single New scheme as for
each New cluster. As with the previous example (i.e., the second
approach, as shown in FIG. 3), this third optional approach can
also have multiple instantiations as multiple clusters become
available (i.e. multiple full clusters remodulated), and may
additionally have the added interim throughput of a partial
cluster, as described in the first exemplary approach, as shown in
FIG. 1. In addition to the partial cluster throughput, the new
modulation and FEC coding of Option 3 is expected to provide as
much as a 45% increase over the combined Legacy/HM Cluster
throughput, resulting in, for example, an additional 500 Kbps of
throughput per cluster.
[0022] FIG. 4 illustrates a simplified drawing of the new
modulation approach of this exemplary third approach, in a new
hybrid receiver shown as "New Receiver (3)" 450. With reference
thereto, downstream of antenna 425, the novel receiver 450 has both
a legacy DEMOD signal path 455 and a NEW DEMOD signal path 457, and
the input signal coming off the air and through antenna 425 is fed
to each of them. The NEW DEMOD signal path 457 has, as noted, a
different modulation scheme than the legacy data clusters. Thus,
full "New" clusters 477 are decoded at the NEW DEMOD module 457 of
the receiver, and "New" Full Cluster Content 477 is obtained.
Additionally, at the legacy DEMOD signal path 455, both Legacy
Content 473 and HM Content 475 are extracted as these clusters were
modulated under the old legacy format. In the depicted example,
there is also New content that is sent within one of the legacy
clusters (but where that whole cluster is not dedicated to New
Content) as per Option 1, above, and thus the output of Legacy
Decode 460 is both (i) "New" Partial Cluster Content 471 as well as
(ii) Legacy Content 473. To correctly extract the "New" Partial
Cluster Content 471 from those combined clusters as per Option 1,
as above, "New" extraction information 470 may be accessed by the
Legacy Decode module 460, as was the case in FIGS. 1 and 3 (Index
Nos. 170 and 370, respectively).
[0023] Thus, the proposed systems and methods described herein
provide a clear approach to achieving better spectral efficiency,
while maintaining backwards compatibility with a legacy
transmission structure. As the complexity of each option increases,
so does the added benefit of additional throughput.
Non-Limiting Software and Hardware Examples
[0024] Various exemplary embodiments of the invention as described
above can be implemented as one or more program products, software
applications and the like, for use with a computer system, both as
to transmission from preparation and as to receiver operations and
processes. The terms program, software application, and the like,
as used herein, are defined as a sequence of instructions designed
for execution on a computer system or data processor. A program,
computer program, or software application may include a subroutine,
a function, a procedure, an object method, an object
implementation, an executable application, an applet, a servlet, a
source code, an object code, a shared library/dynamic load library
and/or other sequence of instructions designed for execution on a
computer system.
[0025] The program(s) of the program product or software may define
functions of the embodiments (including the methods described
herein) and can be contained on a variety of computer readable
media. Illustrative computer readable media include, but are not
limited to: (i) information permanently stored on non-writable
storage medium (e.g., read-only memory devices within a computer
such as CD-ROM disk readable by a CD-ROM drive); (ii) alterable
information stored on writable storage medium (e.g., floppy disks
within a diskette drive or hard-disk drive); or (iii) information
conveyed to a computer by a communications medium, such as through
a computer or telephone network, including wireless communications.
The latter embodiment specifically includes information downloaded
from the Internet and other networks. Such computer readable media,
when carrying computer-readable instructions that direct the
functions of the present invention, represent embodiments of the
present invention.
[0026] In general, the routines executed to implement the
embodiments of the present invention, whether implemented as part
of an operating system or a specific application, component,
program, module, object or sequence of instructions may be referred
to herein as a "program." A computer program typically is comprised
of a multitude of instructions that will be translated by the
native computer into a machine-readable format and hence executable
instructions. Also, programs are comprised of variables and data
structures that either reside locally to the program or are found
in memory or on storage devices. In addition, various programs
described herein may be identified based upon the application for
which they are implemented in a specific embodiment of the
invention. However, it should be appreciated that any particular
program nomenclature that follows is used merely for convenience,
and thus the invention should not be limited to use solely in any
specific application identified and/or implied by such
nomenclature.
[0027] It is also clear that given the typically endless number of
manners in which computer programs may be organized into routines,
procedures, methods, modules, objects, and the like, as well as the
various manners in which program functionality may be allocated
among various software layers that are resident within a typical
computer (e.g., operating systems, libraries, API's, applications,
applets, etc.) It should be appreciated that the invention is not
limited to the specific organization and allocation or program
functionality described herein.
[0028] The present invention may be realized in hardware, software,
or a combination of hardware and software. A system according to a
preferred embodiment of the present invention can be realized in a
centralized fashion in one computer system on the transmit side,
and one receiver on the receive side, or in a distributed fashion
where different elements are spread across several interconnected
computer systems, including cloud connected computing systems and
devices. Any kind of computer system--or other apparatus adapted
for carrying out the methods described herein--is suited. A typical
combination of hardware and software could be a general purpose
computer system with a computer program that, when being loaded and
executed, controls the computer system such that it carries out the
methods described herein.
[0029] Each computer system may include, inter alia, one or more
computers and at least a signal bearing medium allowing a computer
to read data, instructions, messages or message packets, and other
signal bearing information from the signal bearing medium. The
signal bearing medium may include non-volatile memory, such as ROM,
Flash memory, Disk drive memory, CD-ROM, and other permanent
storage. Additionally, a computer medium may include, for example,
volatile storage such as RAM, buffers, cache memory, and network
circuits. Furthermore, the signal bearing medium may comprise
signal bearing information in a transitory state medium such as a
network link and/or a network interface, including a wired network
or a wireless network, that allow a computer to read such signal
bearing information.
[0030] Although specific embodiments of the invention have been
disclosed, those having ordinary skill in the art will understand
that changes can be made to the specific embodiments without
departing from the spirit and scope of the invention. The scope of
the invention is not to be restricted, therefore, to the specific
embodiments. The above-presented description and figures are
intended by way of example only and are not intended to limit the
present invention in any way except as set forth in the following
claims. For example, while this disclosure speaks in terms of
enhancing the bandwidth efficiency of satellite radio broadcasts,
its techniques and systems are applicable to any type of
communications system, transmitting, broadcasting or exchanging
audio, video or other data content. It is particularly noted that
persons skilled in the art can readily combine the various
technical aspects of the various elements of the various exemplary
embodiments that have been described above in numerous other ways,
all of which are considered to be within the scope of the
invention.
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