1. A fluid-gauging probe comprising: a still well arranged to be mounted within a fluid, and at least two acoustic transducer elements mounted towards one end of said still well, wherein said transducer elements are energizable to propagate acoustic energy into fluid within said still well and to receive acoustic energy reflected by a fluid interface within the still well.
2. A fluid-gauging probe according to claim 1, wherein each of said transducer elements is arranged to be energized to propagate energy and each of said transducer elements is arranged to receive energy.
3. A fluid-gauging probe according to claim 1, wherein said probe is operable in a first mode where one said element propagates energy into said fluid and another said element receives the reflected energy, and wherein said probe can be changed to operate in a second mode where one element both propagates and receives energy.
4. A fluid-gauging probe according to claim 3, wherein said probe is arranged to be switched from the first to the second mode when a fault is detected.
5. A fluid-gauging probe according to claim 1, wherein said transducer elements are provided on a common substrate.
6. A fluid-gauging probe according to claim 1, wherein said transducer elements have an electrode common to two said elements.
7. A fluid-gauging probe according to claim 1, wherein said transducer elements are each operable at the same frequency.
8. A fluid-gauging probe according to claim 1, wherein at least two said transducer elements are operable at different frequencies.
9. A fluid-gauging probe according to claim 1, wherein said transducer elements are mounted side-by-side.
10. A fluid-gauging probe according to claim 1, wherein said transducer elements are mounted one above the other.
11. A fluid-gauging probe according to claim 1, wherein said transducer elements are of a piezoelectric ceramic.
12. A fluid-gauging probe comprising: a still well arranged to be mounted within a fluid, and a stack of at least two acoustic transducer elements mounted towards one end of said still well, wherein an electrode is disposed on the upper element in the stack and on the lower surface of the lowest element in the stack, wherein an electrode is disposed between adjacent elements in the stack to provide a lower electrode of an upper element and an upper electrode of a lower element, and wherein said transducer elements are energizable via said electrodes to propagate acoustic energy into fluid within said still well and to receive acoustic energy reflected by a fluid interface within the still well.
13. A fluid-gauging probe according to claim 12, wherein said transducer elements are selectively operable at different frequencies by using different combinations of pairs of electrodes on said elements.
14. A fluid-gauging system comprising: at least one fluid-gauging probe and a unit for driving said probe and receiving signals from said probe, wherein said probe includes a still well arranged to be mounted within a fluid, and at least two acoustic transducer elements mounted towards one end of said still well, wherein said transducer elements are energizable by said unit to propagate acoustic energy into fluid within said still well and to receive acoustic energy reflected by a fluid interface within said still well, and wherein signals produced by said transducer elements are supplied to said unit to derive an indication of fluid quantity.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of decoding extension data for surround, the method comprising:
decoding audio data which is hierarchically encoded;
detecting an identification code which indicates that a payload of the audio data has been completed;
detecting an identification code which indicates that a payload of extension data has been started;
detecting a type of the extension data;
determining whether the detected type shows additional information for decoding the audio data to surround data; and
when it is determined that the detected type shows the additional information, decoding extension data corresponding to the additional data.
2. A method of decoding extension data for surround, the method comprising:
decoding audio data which is hierarchically encoded;
detecting \u2018zero_code\u2019;
detecting \u2018sync_word\u2019;
detecting \u2018extension_type\u2019;
determining whether the detected \u2018extension_type\u2019 shows additional information for decoding the audio data to surround data; and
when it is determined that the detected \u2018extension_type\u2019 shows the additional information, decoding extension data corresponding to the additional data.
3. An apparatus for decoding extension data for surround, the apparatus comprising:
an audio data decoder which decodes audio data that is hierarchically encoded;
a complete code detector which detects an identification code indicating that a payload of the audio data has been completed;
a start code detector which detects an identification code indicating that a payload of extension data has been started;
an extension type detector which detects a type of the extension data;
a determiner which determines whether the detected type shows additional information for decoding the audio data to surround data; and
an extension data decoder which decodes extension data corresponding to the additional information when the determiner determines that the detected type shows the additional information.
4. An apparatus for decoding extension data for surround, the apparatus comprising:
an audio data decoder which decodes audio data that is hierarchically encoded;
a complete code detector which detects \u2018zero_code\u2019;
a start code detector which detects \u2018sync_word\u2019;
an extension type detector which detects \u2018extension_type\u2019;
a determiner which determines whether the detected \u2018extension_type\u2019 shows additional information for decoding the audio data to surround data; and
an additional information decoder which decodes extension data corresponding to the additional information when the determiner determines that the detected \u2018extension_type\u2019 shows the additional information.
5. A non-transitory computer readable recording medium having recorded thereon a program for executing a method of decoding extension data for surround, the method comprising:
decoding audio data which is hierarchically encoded;
detecting an identification code which indicates that a payload of the audio data has been completed;
detecting an identification code which indicates that a payload of extension data has been started;
detecting a type of the extension data;
determining whether the detected type shows additional information for decoding the audio data to surround data; and
when it is determined that the detected type shows the additional information, decoding extension data corresponding to the additional data.
6. A non-transitory computer readable recording medium having recorded thereon a program for executing a method of decoding extension data for surround, the method comprising:
decoding audio data which is hierarchically encoded;
detecting \u2018zero_code\u2019;
detecting \u2018sync_word\u2019;
detecting \u2018extension_type\u2019;
determining whether the detected \u2018extension_type\u2019 shows additional information for decoding the audio data to surround data; and
when it is determined that the detected \u2018extension_type\u2019 shows the additional information, decoding extension data corresponding to the additional data.
7. A method of encoding extension data for surround, the method comprising:
hierarchically encoding audio data;
encoding an identification code which indicates that a payload of the audio data has been completed;
encoding an identification code which indicates that a payload of extension data has been started;
encoding a type of the extension data which shows additional information for decoding the audio data to surround data; and
encoding extension data corresponding to the additional information.
8. A method of encoding extension data for surround, the method comprising:
hierarchically encoding audio data;
encoding \u2018zero_code\u2019;
encoding \u2018sync_word\u2019;
encoding \u2018extension_type\u2019 which shows additional information for decoding the audio data to surround data; and
encoding extension data corresponding to the additional information.
9. An apparatus for encoding extension data for surround, the apparatus comprising:
an audio data encoder which hierarchically encodes audio data;
a complete code encoder which encodes an identification code which shows that a payload of the audio data has been completed;
a start code encoder which encodes an identification code which shows that a payload of extension data has been started;
an extension type encoder which encodes a type of extension data that shows additional information for decoding the audio data to surround data; and
an extension data encoder which encodes extension data corresponding to the additional information.
10. An apparatus for encoding extension data for surround, the apparatus comprising:
an audio data encoder which hierarchically encodes audio data;
a complete code encoder which encodes \u2018zero_code\u2019;
a start code encoder which encodes \u2018sync_word\u2019;
an extension type encoder which detects \u2018extension_type\u2019 that shows additional information for decoding the audio data to surround data; and
an additional information encoder which encodes extension data corresponding to the additional information.
11. A non-transitory computer readable recording medium having recorded thereon a program for executing a method of encoding extension data for surround, the method comprising:
hierarchically encoding audio data;
encoding an identification code which indicates that a payload of the audio data has been completed;
encoding an identification code which indicates that a payload of extension data has been started;
encoding a type of the extension data which shows additional information for decoding the audio data to surround data; and
encoding extension data corresponding to the additional information.
12. A non-transitory computer readable recording medium having recorded thereon a program for executing a method of encoding extension data for surround, the method comprising:
hierarchically encoding audio data;
encoding \u2018zero_code\u2019;
encoding \u2018sync_word\u2019;
encoding \u2018extension_type\u2019 which shows additional information for decoding the audio data to surround data; and
encoding extension data corresponding to the additional information.