Device and method for centimetric-level positioning of a moving object

Device to be positioned relative to a plurality of fixed bases comprising a first counter cyclically browsing a first number n of pointer positions and each base comprising a second counter cyclically browsing the first number n of pointer positions during a period substantially equal to the period for browsing the number n of pointer position by the first counter of the device, wherein:

• the device comprises a first emitter configured to emit a request comprising at least one pattern of points whose values are read with the first counter of the device browsing the number n of pointer positions pointing to memory areas where values of successive points of a pattern can be recorded and read, the emitter of the device modulating a carrier with the values of the points of the pattern of points read successively with the first counter;
• each base of a plurality of fixed bases receiving this request comprises a second emitter configured to respond to the request with a response:
• a) repeating the pattern received by the base from the device, the second counter of the base browsing memory positions of a pattern of at least one pattern of points to enter there values of pattern points then browsing these memory positions to read there the values of pattern points to be emitted, each point of the pattern therefore being temporarily offset, relative to the time of its reception by the base, by a multiple of times the period of the counter of the base and/or
• b) representative of a first temporal pattern offset, measured by the base, between the pattern received and an identical pattern stored in the memory of the base whose values are browsed by the pointer of the base, the values of the points of a response pattern being read successively in memory positions browsed by the pointer of the base, from a position known by the device,
• the emitter of the base modulating a carrier with the values of points of the pattern read successively;
• the device also comprising:
• a means for measuring a second temporal pattern offset between the values of pattern points received in each response and the values stored in the memory of the device in the positions browsed successively by the pointer of the device;
• a means for determining a distance between the device and each base as a function, respectively, of:
• a) a total pattern offset between the pattern emitted by the device and the repeated pattern received by the device from the base;
• b) a second pattern offset and a first pattern offset measured by the base;
• and
• a means for determining the position of the device as a function of a known position of each fixed base having responded and of the distance relative to each of these bases, determined by the determination means.

Base of a plurality of fixed bases for positioning a device comprising a first counter cyclically browsing a first number n of pointer positions and each base comprising a second counter cyclically browsing the first number n of pointer positions during a period substantially equal to the period for browsing the number n of pointer position by the first counter of the device, wherein:

• the device comprises a first emitter configured to emit a request comprising at least one pattern of points whose values are read with the first counter of the device browsing the number n of pointer positions pointing to memory areas where values of successive points of a pattern can be recorded and read, the emitter of the device modulating a carrier with the values of the points of the pattern of points read successively with the first counter;
• each base of a plurality of fixed bases receiving this request comprises a second emitter configured to respond to the request with a response:
• a) repeating the pattern received by the base from the device, the second counter of the base browsing memory positions of a pattern of at least one pattern of points to enter there values of pattern points then browsing these memory positions to read there the values of pattern points to be emitted, each point of the pattern therefore being temporarily offset, relative to the time of its reception by the base, by a multiple of times the period of the counter of the base and/or
• b) representative of a first temporal pattern offset, measured by the base, between the pattern received and an identical pattern stored in the memory of the base whose values are browsed by the pointer of the base, the values of the points of a response pattern being read successively in memory positions browsed by the pointer of the base, from a position known by the device,
• the emitter of the base modulating a carrier with the values of points of the pattern read successively;
• the device also comprising:
• a means for measuring a second temporal pattern offset between the values of pattern points received in each response and the values stored in the memory of the device in the positions browsed successively by the pointer of the device;
• a means for determining a distance between the device and each base as a function, respectively, of:
• a) a total pattern offset between the pattern emitted by the device and the repeated pattern received by the device from the base;
• b) a second pattern offset and a first pattern offset measured by the base;
• and
• a means for determining the position of the device as a function of a known position of each fixed base having responded and of the distance relative to each of these bases, determined by the determination means.

Method for positioning a device in a system comprising this device and a plurality of fixed bases, the device comprising a first counter cyclically browsing a first number n of pointer positions and each base of the plurality of fixed bases comprising a second counter cyclically browsing the first number n of pointer positions during a period substantially equal to the period for browsing the number n of pointer positions by the first counter of the device, method characterised in that it comprises:

• a first step of emission, by the device, of a request comprising at least one pattern of points whose values are read with the first counter of the device browsing the number n of pointer positions pointing to memory areas where values of successive points of a pattern can be recorded and read, the emitter of the device modulating a carrier with the values of points of the pattern of points read successively;
• a second step of emission, by each base of the plurality of fixed bases receiving this request, of a response;
• a) repeating the pattern received by the base from the device, the second counter of the base browsing memory positions of the pattern to enter there the values of pattern points then browsing these memory positions to read there the values of pattern points to be emitted, each point of the pattern therefore being temporarily offset, relative to the time of its reception by the base, by a multiple of times the period of the counter of the base and/or
• b) representative of a first temporal pattern offset, measured by the base, between the pattern received and an identical pattern stored in the memory of the base whose values are browsed by the pointer of the base, the values of the points of a response pattern being read successively in memory positions browsed by the pointer of the base, from a position known by the device,
• the emitter of the base modulating a carrier with the values of points of the pattern read successively;
• a step of the measurement, by the device, of a second temporal pattern offset between the values of pattern points received in each response and the values stored in the memory of the device in the positions browsed successively by the pointer of the device;—a step of the determination, by the device, of a distance between the device and each base of the plurality of fixed bases as a function, respectively, of:
• a) a total pattern offset between the pattern emitted by the device and the repeated pattern received by the device from the base;
• b) a second pattern offset and a first pattern offset measured by the base;
• and
• a step of the determination of the position of the device, by the device, as a function of a known position of each fixed base having responded and of the distance relative to each of these bases, determined by determination means.