1. A navigation signal transmitting apparatus, provided on ground, for transmitting a navigation signal to a receiver capable of positioning by receiving a spread spectrum satellite positioning signal from a satellite, comprising:
first and second transmission antennas;
a message generating unit configured to generate a message signal of positional information included in said navigation signal; and
a modulating unit configured to modulate said message signal by a modulation process including spectrum spreading, based on spread codes of the same sequence as said satellite positioning signal allotted in advance to said navigation signal transmitting apparatus, for generating first and second navigation signals; wherein
said modulating unit is configured to execute said modulating process using either one of said first and second navigation signals as an object of demodulation at each time of reception by said receiver,
said navigation signal transmitting apparatus further comprising:
a transmitting unit configured to transmit said first and second navigation signals from said first and second transmission antennas, respectively.
2. The navigation signal transmitting apparatus according to claim 1, wherein said modulating unit includes:
a first code generating unit configured to generate a first code of said spread codes of the same sequence;
a first spreading unit configured to perform spectrum spreading on said message signal with said first code, to generate said first navigation signal;
a second code generating unit configured to generate a second code of said spread codes of the same sequence, different from said first code; and
a second spreading unit configured to perform spectrum spreading on said message signal with said second code, to generate said second navigation signal.
3. The navigation signal transmitting apparatus according to claim 1, wherein said modulating unit includes:
a spread code generating unit configured to generate a specific code of said spread codes of the same sequence;
a first spreading unit configured to perform spectrum spreading on said message signal with said specific code, to generate said first navigation signal;
a delay unit configured to delay said message signal by a prescribed time period; and
a second spreading unit configured to perform spectrum spreading on an output from said delay unit with said specific code, to generate said second navigation signal.
4. The navigation signal transmitting apparatus according to claim 1, wherein said modulating unit includes:
a spread code generating unit configured to generate a specific code of said spread codes of the same sequence; and
a spreading unit configured to perform spectrum spreading on said message signal with said specific code, and
wherein said transmitting unit is configured to transmit outputs of said spreading unit as said first and second navigation signals, successively and exclusively from either one of said first and second transmission antennas.
5. The navigation signal transmitting apparatus according to claim 1, wherein said positional information includes data representing at least latitude, longitude and altitude.
6. A method of transmitting a navigation signal of a transmitter provided on the ground, for transmitting a navigation signal to a receiver capable of positioning by receiving a spread spectrum satellite positioning signal from a satellite, comprising:
generating a message signal of positional information included in said navigation signal; and
modulating said message signal by a modulation process including spectrum spreading, based on spread codes of the same sequence as said satellite positioning signal allotted in advance to said transmitter, for generating first and second navigation signals;
wherein in said modulation process, either one of said first and second navigation signals is used as an object of demodulation at each time of reception by said receiver;
said method of transmitting a navigation signal further comprising
transmitting said first and second navigation signals from first and second transmission antennas, respectively.
7. The method of transmitting a navigation signal according to claim 6, wherein said generating said first and second navigation signals includes:
generating a first code of said spread codes of the same sequence;
performing spectrum spreading on said message signal with said first code, to generate said first navigation signal;
generating a second code of said spread codes of the same sequence, different from said first code; and
performing spectrum spreading on said message signal with said second code, to generate said second navigation signal.
8. The method of transmitting a navigation signal according to claim 6, wherein said generating said first and second navigation signals includes:
generating a specific code of said spread codes of the same sequence;
performing spectrum spreading on said message signal with said specific code, to generate said first navigation signal;
delaying said message signal by a prescribed time period; and
performing spectrum spreading on said delayed message signal with said specific code, to generate said second navigation signal.
9. The method of transmitting a navigation signal according to claim 6, wherein said generating said first and second navigation signals includes:
generating a specific code of said spread codes of the same sequence;
generating a sequence of pseudo random numbers;
performing spectrum spreading on said message signal with said specific code, to generate said first navigation signal; and
performing spectrum spreading on said message signal with said specific code, to generate said second navigation signal; wherein
said transmitting includes transmitting said first and second navigation signals successively and exclusively from either one of said first and second transmission antennas, based on said pseudo random numbers.
10. The method of transmitting a navigation signal according to claim 6, wherein said positional information includes data representing at least latitude, longitude and altitude.
11. A positional information providing apparatus capable of positioning by receiving a spread spectrum satellite positioning signal from a satellite, providing positional information using a plurality of positioning signals as spread spectrum signals from a navigation signal transmitting apparatus provided on the ground, transmitted using diversity transmission, comprising:
a receiving unit configured to receive said spread spectrum signals;
a storage unit configured to store patterns of a plurality of spread codes of the same sequence as said satellite positioning signal, for said positioning signal;
demodulating units provided in parallel with each other, configured to perform correlation processes commonly and in parallel on said patterns of a plurality of spread codes, for identifying and demodulating said plurality of positioning signals transmitted using diversity transmission; and
a determining unit configured to calculate, if a plurality of said positioning signals are identified and demodulated, said positional information from any of said identified plurality of positioning signals.
12. The positional information providing apparatus according to claim 11, wherein said demodulating unit includes:
a first correlator unit configured to execute a correlation process with a first code of the spread codes of said same sequence;
a second correlator unit configured to execute a correlation process with a second code, different from the first code, of the spread codes of said same sequence; and
a control unit configured to realize control such that using synchronization timing of that one of the first and second correlator units which established synchronization loop earlier, synchronizing process for the other one is executed.
13. The positional information providing apparatus according to claim 11, wherein said demodulating unit includes:
a delay unit configured to delay said received spread spectrum signal by a designated time period;
a first correlator unit configured to execute a correlation process with a first code of the spread codes of the same sequence;
a second correlator unit configured to execute a correlation process with a second code of the spread codes of the same sequence; and
a control unit configured to realize control such that using a spread code of that one of the first and second correlator units which established synchronization loop earlier, synchronizing process for the other one is executed on a signal delayed by a prescribed time period by said delay unit.
14. The positional information providing apparatus according to claim 13, wherein said positional information includes data representing at least latitude, longitude and altitude.
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 child carrier comprising a harness and a pouch, the harness being designed to be worn by a person wishing to carry a child and the pouch being designed to receive a child that the person wishes to carry, the harness including a hip belt, a frame mounted on the hip belt and a load-transmitting fastener formation carried on or forming part of the frame, and the pouch having a load-transmitting fastener formation that is engageable with the load-transmitting fastener formation on the harness whereby, in use, the two load-transmitting fastener formations can be interengaged such that the majority of the weight of the pouch and its contents are transferred via the frame to the hip belt and thus to the hips of the person wearing the harness.
2. A child carrier as claimed in claim 1, in which the pouch has front and back surfaces on each of which there is a load-transmitting fastener formation engageable with the load-transmitting fastener formation on the harness.
3. A child carrier as claimed in claim 1, in which the load-transmitting fastener formation on the harness comprises a socket
4. A child carrier as claimed in claim 1, in which the frame has a configuration corresponding substantially to that of a downwardly facing C.
5. A child carrier as claimed in claim 1, in which there are fixings on the pouch engageable with fixings on the harness to prevent the pouch and its contents moving sideways (relative to the harness) and away from the harnesswearer.
6. A child carrier comprising a first part and a second part, the first part being in the form of a harness designed to be worn by a person carrying a child and the second part being designed to receive a child that the person wishes to carry, the harness including shoulder straps, a hip belt, a frame mounted on the hip belt and a load-transmitting fastener formation arranged to transmit any load that it receives to the frame, and the second part of the child carrier including a load-transmitting fastener formation that is engageable with the load-transmitting fastener formation on the harness whereby, in use, the two load-transmitting fastener formations can be inter-engaged such that the majority of the weight of the second part of the child carrier and its contents are transferred via the frame to the hip belt and thus to the pelvic region of the person wearing the harness.
7. A child carrier as claimed in claim 6, in which the load-transmitting fastener formation on the harness comprises a socket having an upwardly facing open mouth.
8. A child carrier as claimed in claim 6, in which the hip belt is formed with a series of pockets and in which the frame of the harness has downwardly extending end portions selectively engageable in the pockets of the hip belt.
9. A child carrier as claimed in claim 6, in which fixings are mounted on the shoulder straps of the harness and in which complementary fixings are provided on the second part of the child carrier whereby the complementary fixings on the second part of the child carrier can be engaged with the fixings on the shoulder straps to prevent the pouch and its contents moving sideways (relative to the harness) and away from the harnesswearer.
10. A child carrier as claimed in claim 6, in which the second part comprises a pouch having front and back surfaces on each of which there is a load-transmitting formation engageable with the load-transmitting formation on the harness.