U.S. patent application number 09/775519 was filed with the patent office on 2001-06-28 for method and apparatus for feature configuration in remotely located ultrasound imaging system.
This patent application is currently assigned to General Electric Company. Invention is credited to Brackett, Charles Cameron, Johnson, Chandler A., Stratton, Gregory C..
Application Number | 20010005886 09/775519 |
Document ID | / |
Family ID | 22060806 |
Filed Date | 2001-06-28 |
United States Patent
Application |
20010005886 |
Kind Code |
A1 |
Stratton, Gregory C. ; et
al. |
June 28, 2001 |
Method and apparatus for feature configuration in remotely located
ultrasound imaging system
Abstract
A method and apparatus for configuring an ultrasound imaging
system at a remote location by obtaining an encrypted feature key
from a central location (e.g., via telephone) and then inputting
that feature key into the ultrasound imaging system using an
operator interface (e.g., a keyboard). To validate the feature key,
the ultrasound imaging system decrypts the encrypted data and then
compares the decrypted data to validation data pre-stored in the
system. If the decrypted data matches the validation data, then the
optional feature identified by the feature key will be enabled each
time the system is booted or initialized. Optionally, an expiration
date can be associated with the activated option, after which date
the feature will be disabled when the system is initialized.
Similarly, an activated optional feature can be disabled at a
remote location by the input of an encrypted key obtained from a
central location.
Inventors: |
Stratton, Gregory C.;
(Wauwatosa, WI) ; Brackett, Charles Cameron;
(Waukesha, WI) ; Johnson, Chandler A.;
(Oconomowoc, WI) |
Correspondence
Address: |
Dennis M. Flaherty, Esq.
Ostrager Chong & Flaherty LLP
30th Floor
825 Third Avenue
New York
NY
10022-7519
US
|
Assignee: |
General Electric Company
|
Family ID: |
22060806 |
Appl. No.: |
09/775519 |
Filed: |
February 5, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09775519 |
Feb 5, 2001 |
|
|
|
09065171 |
Apr 23, 1998 |
|
|
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Current U.S.
Class: |
713/166 |
Current CPC
Class: |
G01S 7/52017 20130101;
H04L 9/0819 20130101; G01S 15/899 20130101; H04L 9/08 20130101;
H04L 9/088 20130101 |
Class at
Publication: |
713/166 |
International
Class: |
H04L 009/00 |
Claims
1. A method for configuring an ultrasound imaging system at a
remote location, comprising the steps of: storing a validation
identifier inside said system; transmitting an option identifier
which identifies a change in system configuration from said remote
location to a central location; encrypting said validation
identifier and said option identifier at said central location;
transmitting an encrypted feature key comprising a sequence of
characters from said central location to said remote location, said
encrypted feature key comprising said encrypted validation
identifier and said encrypted option identifier; placing said
system in a feature key entry mode; inputting said encrypted
feature key into said system by operation of a sequence of input
keys corresponding to said sequence of characters of said encrypted
feature key; decrypting said encrypted feature key inside said
system to form decrypted data comprising a decrypted validation
identifier and a decrypted option identifier; comparing said
decrypted validation identifier with said stored validation
identifier; altering a system configuration database inside said
system to reflect said change in system configuration only if said
decrypted validation identifier matches said stored validation
identifier.
2. The method as defined in claim 1, wherein said change in system
configuration is addition of an optional feature.
3. The method as defined in claim 1, wherein said change in system
configuration is deletion of an optional feature.
4. The method as defined in claim 1, further comprising the steps
of: transmitting an expiration date associated with said change in
system configuration from said remote location to said central
location; and encrypting said expiration date at said central
location, said encrypted feature key further comprising said
encrypted expiration date and said decrypted data further
comprising a decrypted expiration date, wherein said altering step
further comprises storing said decrypted expiration date in said
system configuration database.
5. The method as defined in claim 1, further comprising the steps
of: constructing a non-singular encryption matrix at said central
location, said encrypting step being carried out by applying said
non-singular encryption matrix to said validation identifier and
said option identifier; and constructing a decryption matrix which
is an inversion of said non-singular encryption matrix at said
remote location, said decrypting step being carried out by applying
said decryption matrix to vectors formed from said encrypted
feature key.
6. The method as defined in claim 1, wherein said validation
identifier comprises a system identifier which uniquely identifies
said ultrasound imaging system.
7. The method as defined in claim 6, wherein said validation
identifier further comprises a key identifier.
8. A method for configuring an ultrasound imaging system,
comprising the steps of: storing a validation identifier inside
said system; placing said system in a feature key entry mode;
inputting an encrypted feature key into said system by operation of
a sequence of input keys corresponding to a sequence of characters,
said encrypted feature key comprising an encrypted validation
identifier and an encrypted option identifier; decrypting said
encrypted feature key inside said system to form decrypted data
comprising a decrypted validation identifier and a decrypted option
identifier; comparing said decrypted validation identifier with
said stored validation identifier; altering a system configuration
database inside said system to reflect a change in system
configuration identified by said decrypted option identifier only
if said decrypted validation identifier matches said stored
validation identifier.
9. The method as defined in claim 8, wherein said change in system
configuration is addition of an optional feature.
10. The method as defined in claim 8, wherein said change in system
configuration is deletion of an optional feature.
11. The method as defined in claim 8, wherein said encrypted
feature key further comprises an encrypted expiration date, said
decrypted data further comprises a decrypted expiration date, said
altering step further comprises storing said decrypted expiration
date in said system configuration database.
12. The method as defined in claim 8, further comprising the step
of constructing a decryption matrix inside said system from
decryption matrix precursor data, wherein said decrypting step is
carried out by applying said decryption matrix to vectors formed
from said encrypted feature key.
13. The method as defined in claim 8, wherein said validation
identifier comprises a system identifier which uniquely identifies
said ultrasound imaging system.
14. The method as defined in claim 13, wherein said validation
identifier further comprises a key identifier.
15. An ultrasound imaging system comprising: an ultrasound
transmitter for transmitting ultrasound energy into a volume of
ultrasound scatterers; a signal processing chain for acquiring
display data representing an image of ultrasound scatterers in said
volume in accordance with a system configuration comprising enabled
features, said display data being based on ultrasound energy
scattered by said ultrasound scatterers; a monitor for displaying
said image in response to receipt of said display data; a memory
for storing a system configuration database representing said
enabled features of said system configuration; an operator
interface comprising a plurality of keys for inputting data into
said system; means for placing said system in a feature key entry
mode in response to a predetermined command input via said operator
interface; and decrypting means for outputting decrypted data in
response to depression of a sequence of keys of said operator
representing an encrypted feature key comprising an encrypted
validation identifier and an encrypted option identifier, said
decrypted data comprising a decrypted validation identifier and a
decrypted option identifier; validating means for determining if
said decrypted validation identifier is valid; and means for
altering said system configuration as a function of said decrypted
option identifier only if said decrypted validation identifier is
valid.
16. The system as defined in claim 15, wherein said change in
system configuration is addition of an optional feature.
17. The system as defined in claim 15, wherein said change in
system configuration is deletion of an optional feature.
18. The system as defined in claim 15, wherein said encrypted
feature key further comprises an encrypted expiration date, said
decrypted data further comprises a decrypted expiration date, said
altering step further comprises storing said decrypted expiration
date in said system configuration database.
19. The system as defined in claim 15, further comprising means for
storing decryption matrix precursor data and means for constructing
a decryption matrix based on said decryption matrix precursor data,
wherein said decrypting means perform decryption by applying said
decryption matrix to vectors formed from said encrypted feature
key.
20. The system as defined in claim 15, wherein said validation
identifier comprises a system identifier which uniquely identifies
said ultrasound imaging system.
21. The system as defined in claim 20, wherein said validation
identifier further comprises a key identifier.
Description
FIELD OF THE INVENTION
[0001] This invention generally relates to systems for ultrasound
imaging of the human anatomy for the purpose of medical diagnosis.
In particular, the invention relates to a method for configuring a
remotely located ultrasound imaging system to add or delete
features.
BACKGROUND OF THE INVENTION
[0002] Conventional ultrasound scanners create two-dimensional
B-mode images of tissue in which the brightness of a pixel is based
on the intensity of the echo return. The basic signal processing
chain in the conventional B mode is depicted in FIG. 1. An
ultrasound transducer array 2 is activated to transmit an acoustic
burst along a scan line. The return RF signals are detected by the
transducer elements and then formed into a receive beam by the
beamformer 4. The beamformer output data (I/Q or RF) for each scan
line is passed through a B-mode processing chain 6 which includes
demodulation, equalization filtering, envelope detection and
logarithmic compression. Depending on the scan geometry, up to a
few hundred vectors may be used to form a single acoustic image
frame. To smooth the temporal transition from one acoustic frame to
the next, some acoustic frame averaging 8 may be performed before
scan conversion.
[0003] In general, the log-compressed display data is converted by
the scan converter 10 into X-Y format for video display. On some
systems, frame averaging may be performed on the X-Y data
(indicated by dashed block 12) rather than the acoustic frames
before scan conversion, and sometimes duplicate video frames may be
inserted between acoustic frames in order to achieve a given video
display frame rate. The scan-converted frames are passed to a video
processor 14, which maps the video data to a gray-scale mapping for
video display. The gray-scale image frames are then sent to a video
monitor 18 for display.
[0004] System control is centered in a host computer 20, which
accepts operator inputs through an operator interface 22 (e.g., a
keyboard) and in turn controls the various subsystems. (In FIG. 1,
only the image data transfer paths are depicted.) During B-mode
imaging, a long sequence of the most recent images are stored and
continuously updated automatically in a cine memory 16. Some
systems are designed to save the R-.theta. acoustic images (this
data path is indicated by the dashed line in FIG. 1), while other
systems store the X-Y video images. The image loop stored in cine
memory 16 can be reviewed via track-ball control, and a section of
the image loop can be selected for hard disk storage.
[0005] For an ultrasound imaging system which has been configured
with a free-hand three-dimensional imaging capability, the selected
image sequence stored in cine memory 16 is transferred to the host
computer 20 for three-dimensional reconstruction. The result is
written back into another portion of the cine memory, from where it
is sent to the display system 18 via video processor 14.
[0006] From the standpoint of the vendor of the ultrasound imaging
system, it is desirable to sell or lease systems having built-in
optional features which can be activated at a location remote from
a central billing station. For example, the capability of free-hand
three-dimensional imaging can be an optional feature which must be
purchased from the system vendor. To ensure that the system user is
charged for the use of such optional features, it is known to
provide means for blocking activation of optional features unless
authorization is obtained from the manufacturer. Authorization can
also be given to allow for use of an optional feature free of
charge for a predetermined trial period. In one conventional
ultrasound system, this is accomplished by delivery of an
authorized feature activation disk, which is inserted into a slot
in the system. The disk has validation information and feature
information stored thereon. The system compares the validation
information with a unique validation standard pre-stored in the
system memory. If the validation data matches the unique pre-stored
standard, the feature information stored on the disk is
incorporated in the system configuration database. Thereafter and
until the expiration date, whenever the system is initialized,
optional feature or features represented by the feature information
of the disk will be enabled.
[0007] However, there is a need for a method of configuring an
ultrasound imaging system at a remote location without physically
transferring an authorization disk or card from the central
location to the remote location. In particular, there is a need for
a method of system configuration which can be carried out remotely
while avoiding the delays inherent in the shipment or delivery of a
disk or card from a central location.
SUMMARY OF THE INVENTION
[0008] The present invention is a method and apparatus for
configuring an ultrasound imaging system at a remote location by
obtaining an encrypted feature key from a central location (e.g.,
via telephone) and then inputting that feature key into the
ultrasound imaging system using an operator interface (e.g., a
keyboard). To validate the feature key, the system decrypts the
encrypted data and then compares the decrypted data to validation
data pre-stored in the system. If the decrypted data matches the
validation data, then the optional feature identified by the
feature key will be enabled each time the system is booted or
initialized. Optionally, an expiration date can be associated with
the activated option, after which date the feature will be disabled
when the system is initialized.
[0009] In accordance with the broad scope of the invention, an
activated optional feature can be disabled at a remote location by
the input of an encrypted key obtained from a central location. The
term "feature key" shall be used hereinafter to mean any key for
activating or deactivating an optional feature.
[0010] To enable an optional feature on the ultrasound system in
accordance with the preferred embodiment of the invention, an
authorized service representative or other user at the remote
location opens a communication link with a central location. In
order to obtain a feature key for enabling the feature, the user
must identify the option desired and provide the machine
identification number and the option expiration date to the central
location. Service personnel at the central location then run a key
maker application using the given data. The key maker application
employs a value extractor to organize the inputted data into
vectors, and an encryption engine to transform those vectors (by
multiplying each vector with a non-singular matrix) into an
encrypted feature key comprising a string of numeric characters.
The encrypted feature key is then communicated to the user at the
remote location.
[0011] To facilitate entry of the encrypted feature activation key
into the system, first the user must enter a predetermined sequence
of alphanumeric characters representing an enter key entry mode
command. The characters can be entered, for example, by depressing
keys located either on a front panel of the system or on a modular
keyboard connected to the system. The enter key entry mode command
places the machine is a suspended state (i.e., the feature key
entry mode) in which the next data inputted into the system is
processed as a feature key. The user then enters the string of
numeric characters representing the encrypted feature key into the
system.
[0012] The ultrasound imaging system at the remote location is
programmed with an encryption engine identical to that used at the
central location to generate the encrypted feature key. After
reading the encrypted feature key (i.e., storing the inputted
numeric characters in a buffer), the system extracts the values
representing the key identifier, machine identification number,
option and option expiration date. The extracted values are then
organized into vectors, which vectors are input into the encryption
engine. The encryption engine de-crypts the encrypted feature key
by linear transformation of the inputted vectors using the matrix
which results when the non-singular matrix used during the
encryption process is inverted. The decrypted vectors representing
the key identifier and machine identification number are then
validated. If the key identifier and machine identification number
are both valid, then the decrypted option and expiration date
vectors are input to an option activator, which copies the option
and expiration date data into the options structure within the
system configuration database. If the expiration date is valid, the
feature identified by the installed option data will be activated
each time that the system is booted, until the expiration date.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a block diagram showing the major functional
subsystems within a conventional real-time ultrasound imaging
system.
[0014] FIG. 2 is a block diagram showing a system for configuring
an ultrasound imaging system at a remote location by obtaining an
encrypted feature key from a central location via a communications
link in accordance with one preferred embodiment of the
invention.
[0015] FIG. 3 is a flowchart showing the steps of a method for
configuring an ultrasound imaging system in accordance with the
preferred embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] FIG. 2 depicts the overall system for feature configuration
of an ultrasound imaging system at a remote location 24 using an
encrypted feature key transmitted from a central location 26.
Although FIG. 2 shows only the host computer 20 and the operator
interface 22 of the ultrasound imaging system, it will be
appreciated that the ultrasound imaging system at remote location
24 may also incorporate the components depicted in FIG. 1 or
components of a different type of ultrasound imaging system.
[0017] The remote location 24 is also provided with a
communications module 28 which can be connected to a communications
module 30 at the central location 26 by opening a communications
link 29. For example, the communications link can be a telephone
line. In accordance with the preferred embodiment of the invention,
to enable an optional feature on the ultrasound imaging system, a
user at the remote location 24 must obtain an encrypted feature key
from the central location. To accomplish this, the user must first
open communications link 29 and then transmit numeric data
representing the option to be activated, the expiration date of
that option and a machine identification number (i.e., serial
number) which is unique to the system being configured.
[0018] After this information has been transmitted, service
personnel at the central location input the transmitted data into
an operator interface 32 which interfaces with a central computer
35. The data is input into the operator interface as a string of
numeric characters. The output of operator interface 32 is input to
a value extractor 34 which is incorporated in central computer 35.
Initially, the string of numeric characters is stored in a buffer
incorporated in the value extractor 34. The central computer also
adds a key identifier to the string of numeric characters. The key
identifier is a special code used to identify a valid feature key.
Optionally, a limit can be placed on the duration of option
activation as represented by the expiration date, e.g., the central
computer may be programmed to reject any request for a feature
activation key made more than 30 days prior to the expiration date.
The value extractor 34 then organizes the string of numeric
characters into a series of vectors in R.sup.x space, where x is
the dimension of a non-singular matrix used in the encryption
process.
[0019] The central computer 35 further comprises an encryption
engine 36 which receives the series of vectors output by the value
extractor 34. To encrypt these vectors, the encryption engine 36
utilizes a non-singular encryption matrix A. The matrix A is
non-singular to allow for decryption using the inverted matrix
A.sup.-1. In accordance with the preferred embodiment of the
invention, the non-singular encryption matrix is not pre-stored,
but rather is generated by the central computer from pre-stored
matrix precursor data. As a result, the encryption matrix cannot be
simply addressed and read out of memory by persons having access to
the central computer, thus providing an added measure of
security.
[0020] After the encryption matrix A has been generated, each
vector V.sub.1 is encrypted by performing the linear transformation
L(V.sub.1)=AV.sub.1. The resulting encrypted vectors form a string
of numeric characters which constitute the encrypted feature key.
The service personnel at the central location 26 then transmit the
encrypted feature key to the remote location 24 via the
communications link 29 or via a different communications link.
[0021] Upon receipt of the encrypted feature key, the user at the
remote location places the ultrasound imaging system in a feature
key entry mode and then inputs the encrypted feature key into the
host computer 20 via the operator interface 22. The encrypted key
is stored in a buffer incorporated in the value extractor 38. The
value extractor 38 parses the string of numeric characters
constituting the encrypted key into the respective values: key
identifier, machine identification number, option and expiration
date, and then organizes those values into respective encrypted
vectors X.sub.1. The encrypted vectors are then decrypted by an
encryption engine 40 using matrix A.sup.-1, i.e., the inverted
non-singular encryption matrix. For added security, the host
computer 20 constructs matrix A.sup.-1 from pre-stored precursor
data. Each encrypted vector X.sub.1 is decrypted by performing the
linear transformation L(X.sub.1)=A.sup.-1X.sub.1. The decrypted key
identifier and machine identification number are output to a key
validator 42. If the key validator determines that both the key
identifier and the machine identification number are valid, then
the key validator generates a signal which enables the option
activator 44. The option activator 44 receives the decrypted option
and expiration date from the encryption engine 40 and copies that
data into respective fields in options data structure 46, which
forms part of the system configuration database. The ultrasound
imaging system is then rebooted automatically. Upon rebooting, the
options handler 48 configures the system in accordance with the new
data stored in the options data structure 46. In particular, the
options handler 48 enables the feature identified by the new
options datum stored in the options field. That feature will be
enabled each time the system is initialized until expiration of the
option on the date indicated in the expiration date field of the
options data structure.
[0022] The method for configuring a remotely located ultrasound
imaging system in accordance with the preferred embodiment of the
invention is shown in more detail in FIG. 3. To facilitate entry of
the encrypted feature key into the system, first the user must
enter a predetermined sequence of alphanumeric characters
representing an enter key entry mode command (step 50). The
characters can be entered, for example, by depressing keys located
either on a front panel of the system or on a modular keyboard
connected to the system. A parameter routine interprets the
predetermined sequence of alphanumeric characters (e.g., the
sequence .DELTA.+2) as the enter key entry mode command, placing
the machine in a suspended state (i.e., the feature key entry
mode). In the feature key entry mode, the next data inputted into
the system will be processed as a feature key.
[0023] In the feature key entry mode, the user enters the string of
numeric characters representing the encrypted feature key into the
operator interface (step 52). Optionally, as the user types in the
encrypted feature key, the system can respond to each key
depression with a form of acknowledgement. The end of the string of
numeric characters is indicated by depressing the "Enter" on the
operator interface. The inputted encrypted key is then read (step
54) by storing the string of numeric characters in a buffer
incorporated in the value extractor 38 (see FIG. 2). The "Read Key"
function is enabled when the user types in the enter key entry mode
command.
[0024] The value extractor parses or extracts the values (step 56)
representing the key identifier, machine identification number,
option and expiration date and then organizes those values into
respective encrypted vectors. The encrypted vectors are then
decrypted (step 58) using the inverted non-singular encryption
matrix, as previously described. The decrypted key identifier data
is then compared with a key identifier pre-stored in the system
configuration database to determine whether the feature key is
valid (step 60). If the feature key is valid, then the machine
identification number, i.e., serial number, is compared with a
machine identification number (also pre-stored in the system
configuration database) which is unique to the system being
configured (step 62). If the machine identification number is
valid, then the decrypted option and expiration date are copied
into respective fields in an options data structure in the system
configuration database (step 70). The ultrasound imaging system is
then rebooted automatically (step 72).
[0025] If either the key identifier or the machine identification
number is invalid (steps 60 and 62 in FIG. 3), then the system
exits the feature key entry mode (step 64). The message "Invalid
Key" is displayed on the monitor (step 66). Then the system returns
to its previous state without rebooting (step 68).
[0026] The foregoing preferred embodiments have been disclosed for
the purpose of illustration. Variations and modifications of the
basic concept of the invention will be readily apparent to persons
skilled in the art. In particular, it will be appreciated that the
encrypted feature key can be transmitted from the central location
to a remote location via a communications link different than the
link used to transmit data from the remote location to the central
location. In addition, although the disclosed preferred embodiments
employ encrypted numeric codes, it will be appreciated that the
system can be readily adapted to operate using encrypted alphabetic
or alphanumeric codes. All such variations and modifications are
intended to be encompassed by the claims set forth hereinafter.
* * * * *