1. A method of detecting symbol timing for a multi-antenna wireless communication system, the method comprising:
at a transmission side, sending a timing training sequence from one antenna alone; and
at a receiving side, receiving the signal sent from the transmission side using a plurality of antennas, calculating a complex correlation amplitude value for signals received by each of the antennas and a time delay of the received signals, synthesizing the complex correlation amplitude value output for each of the antennas, comparing the amplitude after the synthesis with a predetermined threshold value, deciding a rough timing window, carrying out a convolution operation for a symbol sequence of the signal received at each of the antennas and the timing training sequence, synthesizing convolution output results of each of the antennas, searching a final convolution peak value within the rough timing window, and detecting symbol timing.
2. The method of detecting symbol timing for a multi-antenna wireless communication system according to claim 1, wherein the timing training sequence is a short symbol sequence.
3. The method of detecting symbol timing for a multi-antenna wireless communication system according to claim 1, wherein the predetermined threshold value is adaptively adjusted based on channel conditions.
4. The method of detecting symbol timing for a multi-antenna wireless communication system according to claim 1, wherein the multi-antenna wireless communication system is a multi-antenna orthogonal frequency division multiplexing system using a spatial division multiplexing scheme.
5. A method of detecting symbol timing for a multi-antenna wireless communication system, the method comprising:
at a transmission side, sending a timing training sequence from one antenna alone; and
at a receiving side, receiving the signal sent from the transmission side using a plurality of antennas, calculating a complex correlation amplitude value for signals received by each of the antennas and a time delay of the received signals, synthesizing the complex correlation amplitude value output for each of the antennas, comparing the amplitude after the synthesis with a predetermined threshold value, deciding a rough timing window, carrying out a convolution operation for a real part of a symbol sequence of the signal received at each of the antennas and a real part of a timing training sequence, synthesizing convolution output results for each of the antennas, searching a final convolution peak value within the rough timing window, and detecting symbol timing.
6. The method of detecting symbol timing for a multi-antenna wireless communication system according to claim 5, wherein the timing training sequence is a short symbol sequence.
7. The method of detecting symbol timing for a multi-antenna wireless communication system according to claim 5, wherein the predetermined threshold value is adaptively adjusted based on channel conditions.
8. The method of detecting symbol timing for a multi-antenna wireless communication system according to claim 5, wherein the multi-antenna wireless communication system is a multi-antenna orthogonal frequency division multiplexing system using a spatial division multiplexing scheme.
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 for identifying an installed cartridge in a cartridge carrier of an imaging apparatus, said imaging apparatus communicating with said installed cartridge over at least one line, comprising:
sending an ID command to said installed cartridge via an ID line; and
monitoring said ID line for an affirmative response from said installed cartridge, wherein said affirmative response over said ID line indicates that said installed cartridge is a perforator cartridge.
2. The method of claim 1, further comprising, prior to the act of sending,
determining an impedance of a first line coupled to said installed cartridge, wherein an impedance at a first level indicates that said installed cartridge is not said perforator cartridge, and an impedance at a second level indicates the possibility that said installed cartridge is said perforator cartridge; and
if said impedance is at said second level, then performing the act of sending said ID command.
3. The method of claim 2, further comprising, prior to the act of sending, monitoring said ID line for a predefined fixed logic level.
4. The method of claim 1, wherein said imaging apparatus triggers a perforation cycle of said perforator cartridge by driving said ID line to ground for a predetermined period of time.
5. The method of claim 4, wherein following a perforation cycle, said perforator cartridge sends perforator status information to said imaging apparatus via said ID line.
6. The method of claim 1, wherein bi-directional communications over said ID line occurs in the form of a pulse width modulated serial data stream.
7. The method of claim 1, wherein said ID line is also used to identify a printing cartridge using a different communication scheme.
8. An imaging apparatus, comprising:
a cartridge carrier having a cartridge bay having an electrical interface including an ID line, said cartridge carrier being configured to interchangeably receive one of a printing cartridge and a perforator cartridge;
said printing cartridge having electronic circuitry to facilitate an identification of said printing cartridge, said perforator cartridge having an internal electronic configuration that differs from that of said electronic circuitry of said printing cartridge;
a controller communicatively coupled to said electrical interface of said cartridge bay of said carrier and to an installed cartridge present in said cartridge bay, said controller executing program instructions to perform the acts of:
sending an ID command to said installed cartridge present in said cartridge bay via said ID line; and
monitoring said ID line for an affirmative response from said installed cartridge, wherein said affirmative response over said ID line indicates that said installed cartridge is a perforator cartridge.
9. The apparatus of claim 8, said electrical interface including a temperature sense line, said controller executing program instructions to perform the further acts of, prior to the act of sending:
determining an impedance of said temperature sense line coupled to said installed cartridge, wherein an impedance at a first level indicates that said installed cartridge is not said perforator cartridge, and an impedance at a second level indicates the possibility that said installed cartridge is said perforator cartridge; and
if said impedance is at said second level, then performing the act of sending said ID command.
10. The apparatus of claim 9, further comprising, prior to the act of sending, monitoring said ID line for a predefined fixed logic level.
11. The apparatus of claim 8, wherein said imaging apparatus triggers a perforation cycle of said perforator cartridge by driving said ID line to ground for a predetermined period of time.
12. The apparatus of claim 11, wherein following a perforation cycle, said perforator cartridge sends perforator status information to said imaging apparatus via said ID line.
13. The apparatus of claim 8, wherein bi-directional communications over said ID line occurs in the form of a pulse width modulated serial data stream.
14. The apparatus of claim 8, wherein said ID line is also used to identify said printing cartridge using a different communication scheme.
15. A perforator cartridge, comprising a perforator mechanism having an ID line which when driven low performs a perforation operation.
16. The perforator cartridge of claim 15, wherein said perforator cartridge drives said ID line to provide status information as an output over said ID line.