Title: System and method for testing telecommunication devices
Abstract: An invention is provided for testing telecommunications devices. Broadly speaking, test data is encoded prior to testing a SUT. Then, during testing, the encoded test data is transmitted to the SUT, which processes the test data. The processed test data then is received back from the SUT. The processed test data is decoded in real-time, as opposed to the encoding of the test data, which is performed offline and prior to testing. In addition, a quality of the processed test data is analyzed. Typically, the test data is speech data, which is stored prior to testing the SUT. Optionally, the speech data can be encoded offline using a computer system separate from the testing system.
Patent Number: 6,898,272 Issued on 05/24/2005 to Talalai
| Inventors:
|
Talalai; Alexander (Palo Alto, CA)
|
| Assignee:
|
Spirent Communications (Rockville, MD)
|
| Appl. No.:
|
211715 |
| Filed:
|
August 1, 2002 |
| Current U.S. Class: |
379/10.03; 375/224; 375/242; 379/22.01; 379/22.02; 379/28; 379/29.01 |
| Intern'l Class: |
H04M 001/24; H04M003/08; H04M003/22 |
| Field of Search: |
379/101,102,906,100.1,100.3,150.1,220.2,260.1,290.1,290.2,31
375/220,221,222,224,225,242
714/715,716
|
References Cited [Referenced By]
U.S. Patent Documents
| 5535299 | Jul., 1996 | Riedel.
| |
| 5572570 | Nov., 1996 | Kuenzig.
| |
| 5633909 | May., 1997 | Fitch.
| |
| 5907827 | May., 1999 | Fang et al.
| |
| 5933475 | Aug., 1999 | Coleman.
| |
| 5940472 | Aug., 1999 | Newman et al.
| |
| 6189127 | Feb., 2001 | Fang et al.
| |
| 6304634 | Oct., 2001 | Hollier et al.
| |
| 6308065 | Oct., 2001 | Molinari et al.
| |
| 6411623 | Jun., 2002 | DeGollado et al.
| |
| 6574280 | Jun., 2003 | Liau et al.
| |
| 2003/0068982 | Apr., 2003 | Barrett et al.
| |
| 2004/0190494 | Sep., 2004 | Bauer.
| |
| 2004/0193974 | Sep., 2004 | Quan et al.
| |
Primary Examiner: Tieu; Binh
Attorney, Agent or Firm: Martine Penilla & Gencarella, LLP
Claims
1. A method for testing telecommunications devices, comprising the operations of:
encoding test data prior to testing a system under test (SUT);
transmitting the encoded test data to the SUT, the SUT processing the test data;
receiving the processed test data from the SUT;
decoding the processed test data in real-time; and
analyzing a quality of the processed test data,
wherein the method operation of encoding the test data includes compressing the
test data for transmission to the SUT.
2. A method as recited in claim 1, wherein the test data is speech data.
3. A method as recited in claim 2, further comprising the operation of storing
the encoded speech data prior to testing the SUT.
4. A method as recited in claim 1, wherein a testing system is used to decode
the processed test data.
5. A method as recited in claim 4, wherein the speech data is encoded offline
using a computer system separate from the testing system.
6. A method as recited in claim 1, further comprising the operation of comparing
the processed test data to reference speech data to obtain speech quality result data.
7. A method as recited in claim 6, further comprising the operation of storing
the speech quality result data to a quality of service (QoS) data file.
8. The method of claim 1 wherein the compressing the test data is defined by
one of a pulse code modulation (PCM) format and an adaptive differential PCM (ADPCM) format.
9. A system for testing telecommunication devices, comprising:
an encoder that encodes test data prior to testing a system under test (SUT),
the test data being compressed by the encoder for transmission to the SUT; and
a decoder that decodes processed test data received from the SUT in real-time
during testing of the SUT.
10. A system as recited in claim 9, further comprising memory that stores the
encoded test data prior to testing the SUT.
11. A system as recited in claim 10, wherein the stored encoded test data is
transmitted to the SUT during testing of the SUT, the SUT processing the test data
and transmitting the processed test data to the system.
12. A system as recited in claim 9, wherein the encoder is executed on a computer
separate from a computer executing the decoder.
13. A system as recited in claim 9, wherein the test data is speech data.
14. A system as recited in claim 13, further comprising speech quality comparison
logic that analyzes the quality of the processed speech data.
15. A system as recited in claim 14, wherein the speech quality comparison logic
compares the processed speech data to reference speech data to obtain speech quality
result data.
16. A system as recited in claim 15, wherein the speech quality result data is
stored in a quality of service (QoS) data file.
17. A computer program embodied on a computer readable medium for testing telecommunication
devices, the computer program comprising:
an encoder code segment that encodes test data prior to testing a system under
test (SUT), the test data being compressed by the encoder code segment for transmission
to the SUT; and
a decoder code segment that decodes processed test data received from the SUT
in real-time during testing of the SUT.
18. A computer program as recited in claim 17, wherein the test data is speech data.
19. A computer program as recited in claim 18, further comprising a code segment
that stores the encoded speech data prior to testing the SUT.
20. A computer program as recited in claim 17, further comprising a code segment
that compares the processed test data to reference speech data to obtain speech
quality result data.
21. A computer program as recited in claim 20, further comprising a code segment
that stores the speech quality result data to a quality of service (QoS) data file.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to telecommunication, and more particularly
to high density telecommunication testing.
2. Description of the Related Art
Today, modern telecommunications systems often perform complex operations,
such as data compression, when transmitting signals through the telecommunications
network. These operations generally have non-linear effects on the signal inputs.
As a result, it is often not possible to model the effects of the network by simulating
the additive affect of each component of the network. In particular, the affect
of the network on speech is not easily derivable from studying the network's affect
on a simple test signal such as a sine wave.
Hence, voice communication signals generally are tested using voice generation
and analyzing equipment in the form of a telecommunication testing system. FIG.
1 is a block diagram showing an exemplary conventional telecommunication testing
configuration
100. As shown in FIG. 1, the telecommunication testing configuration
100 includes a system under test (SUT)
102, such as a telecommunication
system, in communication with a test system
104. As mentioned above, one
technique for testing the SUT
102 for voice QoS is call generation.
Call Generation is a testing mode in which the test system
104 creates
telephone traffic by executing compiled call sequences (scripts). To test the SUT
102, the test system
104 provides a maximal load on the SUT
102.
In particular, the test system
104 places data on the input channels of
the SUT
102, and receives and analyzes the output data quality of the SUT
102 in real time.
In order to reduce the amount of data passing through the communication lines,
the data is compressed before transmitting and decompressed after receiving using
speech codecs, often referred to as vocoders. As shown in FIG. 1, the SUT
102
includes a codec
106a, and the test system
104 includes a
similar codec
106b. In this manner, the test system
104 can
encode speech data using the codec
106b. The test system
104
then transmits the encoded speech data to the SUT
102, which decodes the
speech data using the codec
106a of the SUT
102. Similarly,
the SUT
102 encodes speech data using the codec
106a and transmits
the encoded speech data to the test system
104. The test system then decodes
the speech data using the codec 106b of the test system
104.
FIG. 2 shows an exemplary conventional speech codec
106 for encoding
and decoding speech data. The speech codec
200 is a hardware circuit (chip)
or software/firmware routine that converts the spoken word into digital code and
vice versa. In particular, a speech codec is an audio codec specialized for human
voice. By analyzing vocal tract sounds, a recipe for rebuilding the sound at the
other end is sent rather than the soundwaves themselves. As a result, the speech
codec is able to achieve a much higher compression ratio than regular audio codecs,
which yields a smaller amount of digital data for transmission.
As shown in FIG. 2, the speech codec
106 includes an encoder
200
and a decoder
202. The codec
106 both encodes and decodes speech
data using the encoder
200 and the decoder
202 respectively. For
example, in a SUT, the codec
106 can be used to transform data between Pulse
Code Modulation (PCM) format and Adaptive Differential PCM (ADPCM) format.
PCM is a technique for converting analog signals into digital form that is widely
used by the telephone companies in their T1 circuits. For example, telephone conversations,
as well as data transmissions via modem, are converted into digital via PCM for
transport over high-speed intercity trunks. In North America and Japan, PCM samples
the analog waves 8,000 times per second and converts each sample into an 8-bit
number, resulting in a 64 Kbps data stream (a single DS
0 channel). The sampling
rate is twice the 4 kHz bandwidth required for a toll-quality conversation. ADPCM
is an advanced PCM technique that converts analog sound into digital data and vice
versa. Instead of coding an absolute measurement at each sample point, it codes
the difference between samples and can dynamically switch the coding scale to compensate
for variations in amplitude and frequency.
Thus, for example, the decoder
202 section of the codec
106 can
receive a PCM signal from the telecommunications network. Once received, the decoder
202 can decode the PCM signal and provide the uncompressed speech data to
the telecommunications system, which processes the signal. Thereafter, the telecommunications
system uses the encoder
200 to encode the uncompressed data into, for example,
an ADPCM signal and transmits. In this manner, the codec
106 allows a system
to receive and process PCM data and transmit ADPCM data. To test such a system,
the test system can include an encoder that encodes PCM data and a decoder that
decodes ADPCM data.
For example, referring back to FIG. 1, when testing the SUT
102, the test
system
104 encodes speech data using the codec
106b. For example,
the codec can encode uncompressed speech test data into PCM format. The test system
then transmits the encoded PCM data to the SUT
102, which uses the codec
106a to decode the PCM data for processing. The SUT
102 can
then encode the speech data into, for example, ADPCM format and transmit the encoded
data back to the test system
104. The test system then decodes the ADPCM
speech data using the codec
106b and analyses the speech data for quality.
Unfortunately, test systems
104 using call generation typically
cannot support a large amount of data channels without distorting the performance
of the SUT
102. For example, if the SUT
102 can support, for example,
300 simultaneous data channels, a typical testing system
104 can only support,
for example, about 100 simultaneous data channels. As a result, three testing systems
104 would be needed to test the performance of the SUT
102.
In view of the foregoing, there is a need for systems and methods for high density
telecommunication testing. The systems and methods should be capable of performing
quality of service (QoS) testing on the SUT, and further, should support an increased
number of simultaneous data channels without distorting the performance of the SUT.
SUMMARY OF THE INVENTION
Embodiments of the present invention fills these needs by providing a
telecommunications testing system that supports an increased number of simultaneous
data channels. To this end, embodiments of the present invention separate the encoder
and decoder of the testing system codec, which allows offline encoding of test
data, which greatly increases the density support of the testing system. In one
embodiment, a method is disclosed for testing telecommunications devices. Broadly
speaking, test data is encoded prior to testing a SUT. Then, during testing, the
encoded test data is transmitted to the SUT, which processes the test data. The
processed test data then is received back from the SUT. The processed test data
is decoded in real-time, as opposed to the encoding of the test data, which is
performed offline and prior to testing. In addition, a quality of the processed
test data is analyzed. Typically, the test data is speech data, which is stored
prior to testing the SUT. Optionally, the speech data can be encoded offline using
a computer system separate from the testing system.
In an additional embodiment, a system for testing telecommunication devices is
disclosed. The system includes an encoder that encodes test data prior to testing
a SUT, and a decoder that decodes processed test data received from the SUT in
real-time during testing of the SUT. Optionally, the system can include memory
that stores the encoded test data prior to testing the SUT. In this case, the stored
encoded test data can be transmitted to the SUT during testing of the SUT, where
the SUT processes the test data and transmits the processed test data to the system.
Further, speech quality comparison logic can be included that analyzes the quality
of the processed speech data. Optionally, the speech quality comparison logic can
compare the processed speech data to reference speech data to obtain speech quality
result data, which can be stored in a quality of service (QoS) data file.
A computer program embodied on a computer readable medium for testing telecommunication
devices is disclosed in a further embodiment of the present invention. The computer
program includes an encoder code segment that encodes test data prior to testing
a SUT, and a decoder code segment that decodes processed test data received from
the SUT in real-time during testing of the SUT. As above, the test data generally
is speech data. Optionally, the computer program can include a code segment that
stores the encoded speech data prior to testing the SUT, and a code segment that
compares the processed test data to reference speech data to obtain speech quality
result data. Similar to above, the computer program can further include a code
segment that stores the speech quality result data to a QoS data file.
Advantageously, by separating the encoding functions from the decoding
functions, embodiments of the present invention require approximately half the
resources required by conventional test systems, which utilize codecs to perform
SUT testing. As a result, embodiments of the present invention can increase by
approximately two times the number of data channels that the test system can support.
Thus, embodiments of the present invention can support twice the data channels
that can be supported using conventional telecommunication testing systems. Other
aspects and advantages of the invention will become apparent from the following
detailed description, taken in conjunction with the accompanying drawings, illustrating
by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention, together with further advantages thereof, may best be understood
by reference to the following description taken in conjunction with the accompanying
drawings in which:
FIG. 1 is a block diagram showing an exemplary conventional telecommunication
testing configuration;
FIG. 2 shows an exemplary conventional speech codec for encoding and decoding
speech data;
FIG. 3A is a block diagram showing an exemplary telecommunication testing configuration,
in accordance with an embodiment of the present invention;
FIG. 3B is a block diagram showing an exemplary telecommunication testing configuration
having a separated encoder, in accordance with an embodiment of the present invention;
FIG. 4 is a block diagram showing a telecommunication test system, in accordance
with an embodiment of the present invention;
FIG. 5 is a flowchart showing a method for preprocessing test data for testing
telecommunications devices, in accordance with an embodiment of the present invention; and
FIG. 6 is a flowchart showing a method for testing a telecommunication device,
in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An invention is disclosed for a telecommunications testing system that supports
an increased number of simultaneous data channels. Broadly speaking, embodiments
of the present invention separate the encoder and decoder of the testing system
codec, thus allowing offline encoding of testing data, which greatly increases
the density support of the testing system. In the following description, numerous
specific details are set forth in order to provide a thorough understanding of
the present invention. It will be apparent, however, to one skilled in the art
that the present invention may be practiced without some or all of these specific
details. In other instances, well known process steps have not been described in
detail in order not to unnecessarily obscure the present invention.
FIG. 3A is a block diagram showing an exemplary telecommunication testing configuration
300, in accordance with an embodiment of the present invention. The telecommunication
testing configuration
300 includes a testing system
302 in communication
with a SUT
102, which includes, as discussed above, a codec
106 that
provides encoding and decoding of speech data.
In place of a conventional codec, the test system
302 includes an encoder
304 and a decoder
306, which operate independent of each other. Broadly
speaking, the encoder
304 encodes test data prior to testing the SUT
102.
Then, during testing of the SUT, the decoder
306 decodes, in real-time,
processed test data received from the SUT.
More particularly, prior to testing the SUT
102, test data is provided
to the encoder
304. As mentioned above, one technique for testing the SUT
102 for voice QoS is call generation, which is a testing mode in which the
test system
302 creates telephone traffic by executing compiled call sequences.
To test the SUT
102, the test system
302 places data on the input
channels of the SUT
102, and receives and analyzes the output data quality
of the SUT
102 in real-time.
As mentioned above, the test data is compressed before transmitting and decompressed
after being received in order to reduce the amount of data passing through the
communication lines. Generally, the task of encoding data is much more computationally
expensive than the task of decoding data. For example, in most cases a decoder
can execute five to ten times faster than an encoder. Moreover, a decoder generally
utilizes less memory for program body and data. Furthermore, an encoding task can
utilize more resources than a decoding task and quality evaluation task together.
Hence, embodiments of the present invention separate the task of encoding
the test data from the task of decoding the test data. In particular, the encoding
is performed offline, prior to testing the SUT, when encoder processing time is
not an issue. For example, reference test data, such as speech data is provided
to the encoder
304, which encodes the test data. The encoded test data is
then stored for future testing. As will be appreciated, the encoder
304
can perform encoding operations at any time prior to testing the SUT. For example,
the encoder
304 can encode the test data hours or days before actual testing
of the SUT
102. Once the test data is encoded, the encoder
304 generally
is no longer utilized during testing of the SUT
102.
Specifically, during actual testing of the SUT
102, the stored
test data is transmitted to the SUT
102. Because the test data has been
previously encoded prior to testing the SUT
102, the encoder
304
is not required to perform any encoding operations during testing of the SUT
102.
As a result, embodiments of the present invention perform decoding operations,
which are five to ten times faster than encoding operations, during testing of
the SUT
102 without requiring encoding operations.
Thus, the test system
302 transmits the encoded speech data to the SUT
102, which decodes the speech data using the codec
106 and processes
the decoded speech data. The SUT
102 then encodes the processed speech data
using the codec
106 and transmits the encoded speech data to the test system
302. The test system then decodes the speech data using the decoder
306
of the test system
302. Thereafter, the test system
302 analyzes
the speech data.
In one embodiment, as will be described in greater detail below, the test system
302 includes speech quality comparison logic that analyzes the quality of
the processed speech data. The speech quality comparison logic compares the processed
speech data to reference speech data to obtain speech quality result data, which
then can be stored in a quality of service (QoS) data file for later use.
Since the encoder
304 and decoder
306 are separate, embodiments
of the present invention can execute the encoder
304 on a separate computer
system than that executing the decoder
306, as shown in FIG.
3B.
FIG. 3B is a block diagram showing an exemplary telecommunication testing configuration
350 having a separated encoder
304, in accordance with an embodiment
of the present invention. The telecommunication testing configuration
350
includes a testing system
352 in communication with a SUT
102, which
includes, as discussed above, a codec
106 that provides encoding and decoding
of speech data.
As shown in FIG. 3B, the encoder
304 can be separated from the test system
352 to provide additional flexibility in offline encoding of the speech
test data. For example, the encoder
304 can be executed on a general purpose
personal computer, which can be located separately from the test system
352.
Moreover, as mentioned above, the encoder
304 can be used to encode the
test data anytime prior to conducting the test on the SUT
102. For example,
the encoder
304 can be executed days before actual SUT testing using a personal
computer located at a separate location. Further, the encoded speech data can be
stored as one or more data files, which can be later transferred to the test system
352 using, for example, removable storage such as floppy disks, CD-Rs, CD-RWs,
and/or DVDs. Optionally, the encoded speech data can be transmitted to the test
system
352 using a network, such as a local area network (LAN) and/or a
wide area network (WAN), such as the Internet.
Similar to FIG. 3A, in the embodiment of FIG. 3B the stored test data is
transmitted to the SUT
102 during actual testing of the SUT
102.
Because the test data has been previously encoded prior to testing the SUT
102,
the encoder
304 is not required to perform any encoding operations during
testing of the SUT
102. As a result, embodiments of the present invention
perform decoding operations, which are five to ten times faster than encoding operations,
during testing of the SUT
102 without requiring encoding operations.
Thus, once the test system
352 receives the encoded speech data, the
test system
352 transmits the encoded speech data to the SUT
102,
which decodes the speech data using the codec
106 and processes the decoded
speech data. The SUT
102 then encodes the processed speech data using the
codec
106 and transmits the encoded speech data to the test system
352.
The test system then decodes the speech data using the decoder
306 of the
test system
352. Thereafter, the test system
352 analyzes the speech data.
Advantageously, by separating the encoding functions from the decoding
functions, as described above with reference to FIGS. 3A and 3B, embodiments of
the present invention require approximately half the resources required by conventional
test systems, which utilize codecs to perform SUT testing. As a result, embodiments
of the present invention can increase by approximately two times the number of
data channels that the test system can support. Thus, embodiments of the present
invention can support twice the data channels that can be supported using conventional
telecommunication testing systems.
FIG. 4 is a block diagram showing a telecommunication test system
302,
in accordance with an embodiment of the present invention. The test system
302
includes an encoder
304 and a decoder
306. In communication with
both the encoder
304 and the decoder
306 is processing logic
400
that coordinates the processing flow of the various system components. Further,
speech quality comparison logic
402 is included that determines the QoS
of the SUT. Coupled to the encoder
304 is a data bank
408, which
is used to store the encoded speech data
410.
As mentioned above, embodiments of the present invention preprocess the test
data
prior to testing the SUT. In one embodiment, the encoder
304 receives a
test data file
404, which includes speech data that will be utilized as
test data for the SUT. For example, the speech data can comprise a plurality of
spoken sentences specifically selected to test various aspects of the SUT. To reduce
the amount of data transmitted on the data channels, the speech data from the test
data file
404 is compressed using the encoder
304, which encodes
the speech data into a format the SUT will expect to receive. The encoded speech
data
410 then is stored in the data bank
408 for later use during
testing of the SUT. As mentioned previously, the encoder
304 can perform
encoding operations at any time prior to testing the SUT. For example, the encoder
304 can encode the test data hours or days before actual testing of the
SUT. Once the test data is encoded, the encoder
304 generally is no longer
utilized during testing of the SUT.
During actual testing of the SUT, the stored encoded speech data
410
is transmitted to the SUT. Because the speech data has been previously encoded
prior to testing the SUT, the encoder
304 is not required to perform any
encoding operations during SUT testing. As a result, embodiments of the present
invention, without requiring encoding operations, are free to perform decoding
operations, which are five to ten times faster than encoding operations, during
testing of the SUT.
Thus, the test system
302 transmits the encoded speech data
410
to the SUT, which decodes and processes the decoded speech data. The SUT then encodes
the processed speech data using a codec and transmits the encoded speech data to
the test system
302. The test system then decodes the speech data using
the decoder
306 of the test system
302. The test system
302
can then analyze the speech data using the speech quality comparison logic
402.
The speech quality comparison logic compares the processed speech data to reference
speech data, such as the test data file
404, to obtain speech quality result
data, which can then be is stored in a QoS data file
406 for later use.
The QoS data file
406 can be stored, for example, on mass storage and/or
removable storage such as floppy disks, CD-Rs, CD-RWs, and/or DVDs. Optionally,
the QoS data file
406 can be transmitted to other computer systems using
a network, such as a local area network (LAN) and/or a wide area network (WAN),
such as the Internet.
As discussed above, embodiments of the present invention advantageously require
approximately half the resources required by conventional test systems, which utilize
codecs to perform SUT testing. As a result, embodiments of the present invention
can support twice the data channels that can be supported using conventional telecommunication
testing systems.
As will be appreciated, a test system of the embodiments of the present invention
can originate and terminate a call through a switch or similar telecommunication
device. Moreover, the circuit type of the originating channel can be the same as
or different from that of the terminating channel. That is, the encoder
304
can encode the speech data into one particular format, such as PCM, and the decoder
306 can be designed to receive and decode data encoded in a different format,
such as ADPCM. As such, embodiments of the present invention can be utilized to
create multiple telephone calls, answer calls, confirm that calls are correctly
established, create and respond to unique tones, measure and display call statistics
in real time, and generate calls on one circuit type and terminate calls on another
circuit type.
FIG. 5 is a flowchart showing a method
500 for preprocessing test data
for testing telecommunications devices, in accordance with an embodiment of the
present invention. As discussed above, embodiments of the present invention separate
the encoder and decoder of the testing system codec. This allows offline encoding
of testing data, which greatly increases the density support of the testing system.
In an initial operation
502, preprocess operations are performed. Preprocess
operations can include, for example, defining a test job, provisioning the test
system into the system having the SUT, and other preprocess operations that will
be appreciated with those skilled in the art after a careful reading of the present disclosure.
In operation
504, a test job is received that defines a set of data and
data compression types. Generally, embodiments of the present invention utilize
call generation to test the SUT. As such, the test job defines the set of speech
data that will be encoded and sent to the SUT and later analyzed for QoS. In addition
to the speech data, the data compression types that will be utilized during the
test are defined in the test job. The data compression types can vary from input
to output as mentioned above with reference to FIG.
4. For example, a particular
SUT may expect data encoded as PCM as an input and may encode speech data in ADPCM
format at the output.
The speech data is then encoded offline and stored in memory prior to testing
the SUT, in operation
506. As mentioned above with reference to FIG. 3B,
the encoder can be separated from the test system to provide additional flexibility
in offline encoding of the speech test data. For example, the encoder can be executed
on a general purpose personal computer, which can be located separately from the
test system. Moreover, as mentioned above, the encoder can be used to encode the
test data anytime prior to conducting the test on the SUT. For example, the encoder
can be executed days before actual SUT testing using a personal computer located
at a separate location. Furthermore, the encoded speech data can be stored as one
or more data files, which can be later transferred to the test system using, for
example, removable storage such as floppy disks, CD-Rs, CD-RWs, and/or DVDs. Optionally,
the encoded speech data can be transmitted to the test system using a network,
such as a local area network (LAN) and/or a wide area network (WAN), such as the Internet.
Post process operations are performed in operation
508. Post process
operations can included, for example, testing the SUT, analyzing test results,
and other post process operations that will be apparent to those skilled in the
art after a careful reading of the present disclosure. Because the speech data
has been previously encoded prior to testing the SUT, the encoder is not required
to perform any encoding operations during SUT testing. As a result, embodiments
of the present invention, without requiring encoding operations, are free to perform
decoding operations, which are five to ten times faster than encoding operations,
during testing of the SUT.
FIG. 6 is a flowchart showing a method
600 for testing a telecommunication
device, in accordance with an embodiment of the present invention. As discussed
above, embodiments of the present invention preprocess and encode test data prior
to testing the SUT. In this manner, computationally expensive encoding operations
are not required during SUT testing, which enables embodiments of the present invention
to use extra resources to facilitate decoding and analysis operations. As a result,
increased channel density can be achieved using the embodiments of the present
invention. In an initial operation
602, preprocess operations are performed.
Preprocess operations include encoding the test data in a format the SUT will expect,
storing the encoded data on the test system, and other preprocess operations that
will be apparent to those skilled in the art after a careful reading of the present disclosure.
In operation
604, the compressed speech data is transmitted to the SUT
using predefined data channels. During actual testing of the SUT, the stored speech
data is transmitted to the SUT. Because the test data has been previously encoded
prior to testing the SUT, the encoder is not required to perform any encoding operations
during testing of the SUT. As a result, embodiments of the present invention perform
decoding operations, which are five to ten times faster than encoding operations,
during testing of the SUT without requiring encoding operations.
The encoded processed speech data is received from the SUT and decoded using
the test system decoder, in operation
606. In response to receiving the
encoded speech data from the test system, the SUT decodes the speech data using
its codec and processes the decoded speech data. The SUT then uses the codec to
encode the processed speech data and transmits the encoded speech data to the test
system. Then, in operation
606, the test system receives and decodes the
speech data using the decoder of the test system.
In operation
608, the decoded speech data is compared to reference speech
data. The test system analyzes the QoS provided by the SUT by comparing the speech
data received from the SUT to reference speech data. In one embodiment, the test
system uses speech quality comparison logic to compare the processed speech data
to reference speech data, such as from a test data file, to obtain speech quality
result data.
The Comparison results are stored to a QoS data file in operation
610.
The speech quality result data is stored in a QoS data file, which can be stored,
for example, on mass storage and/or removable storage such as floppy disks, CD-Rs,
CD-RWs, and/or DVDs. Optionally, the QoS data file can be transmitted to other
computer systems using a network, such as a local area network (LAN) and/or a wide
area network (WAN), such as the Internet.
Post process operations are performed in operation
612. Post process
operations can include for example, analysis of the QoS data file, comparison of
the QoS data file to prior QoS data files, and other post process operations that
will be apparent to those skilled in the art after a careful reading of the present
disclosure. As discussed above, by separating the encoding functions from the decoding
functions, embodiments of the present invention require approximately half the
resources required by conventional test systems, which utilize codecs to perform
SUT testing. As a result, embodiments of the present invention advantageously can
increase by approximately two times the number of data channels that the test system
can support. Thus, embodiments of the present invention can support twice the data
channels that can be supported using conventional telecommunication testing systems.
The invention may employ various computer-implemented operations involving data
stored in computer systems. These operations are those requiring physical manipulation
of physical quantities. Usually, though not necessarily, these quantities take
the form of electrical or magnetic signals capable of being stored, transferred,
combined, compared, and otherwise manipulated. Further, the manipulations performed
are often referred to in terms, such as producing, identifying, determining, or comparing.
Any of the operations described herein that form part of the invention are useful
machine operations. The invention also relates to a device or an apparatus for
performing these operations. The apparatus may be specially constructed for the
required purposes, or it may be a general purpose computer selectively activated
or configured by a computer program stored in the computer. In particular, various
general purpose machines may be used with computer programs written in accordance
with the teachings herein, or it may be more convenient to construct a more specialized
apparatus to perform the required operations.
The invention can also be embodied as computer readable code on a computer readable
medium. The computer readable medium is any data storage device that can store
data, which can thereafter be read by a computer system. Examples of the computer
readable medium include read-only memory, random-access memory, CD-ROMs, CD-Rs,
CD-RWs, magnetic tapes, and other optical data storage devices. The computer readable
medium can also be distributed over network coupled computer systems so that the
computer readable code is stored and executed in a distributed fashion.
Although the foregoing invention has been described in some detail for purposes
of clarity of understanding, it will be apparent that certain changes and modifications
may be practiced within the scope of the appended claims. Accordingly, the present
embodiments are to be considered as illustrative and not restrictive, and the invention
is not to be limited to the details given herein, but may be modified within the
scope and equivalents of the appended claims.
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