We claim:
1. An exhaust gas treatment device for an internal combustion engine, comprising;
a housing having portions defining an inlet, an outlet and an interior chamber between said inlet and said outlet;
at least one exhaust gas treating body located between said inlet within said chamber and said outlet;
a first support material located radially between an inner surface of said housing and said at least one exhaust gas treating body;
an internal shield located within said housing;
a second support material radially surrounding said internal shield and located between said inner surface of said housing and said internal shield, said second support material retaining said internal shield in engagement within said housing;
wherein said housing exhibits a substantially constant cross sectional area along its axial length in a region proximal to said internal shield.
2. A device as set out in claim 1 wherein said second support material has a second axial length, said internal shield has a first axial length, and said second axial length being not greater than said first axial length.
3. A device as set out in claim 1 wherein said first support material does not extend into areas radially between said internal shield and said housing.
4. A device as set out in claim 1 wherein said first support material is axially restricted to areas radially adjacent to said at least one exhaust gas treating body.
5. A device as set out in claim 1 wherein said second support material is in an interference fit between said internal shield and said housing.
6. A device as set out in claim 1 wherein said first support material is in an interference fit between said at least one exhaust gas treating body and said housing.
7. A device as set out in claim 1 wherein said internal shield includes at least one flared axial end.
8. A device as set out in claim 1 wherein said at least one flared axial end is radially outwardly flared.
9. A device as set out in claim 1 wherein said first support material retainingly engages said at least one exhaust gas treating body with said housing.
10. A device as set out in claim 1 further comprising a sensor mounted to said housing and extending through said housing, said second support material and said internal shield, said sensor terminating at a location within an internal diameter of said internal shield and within a flow path of exhaust gases.
11. A device as set out in claim 1 wherein said second support material is a thermal insulation material.
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 MIMO-CDMA wireless communication equipment, comprising a transmitter and a receiver, wherein the transmitter comprises:
an encoder for receiving a plurality of transmission data and encoding them;
a quadrature phase-shift keying (QPSK) unit for conducting QPSK modulating to an output of the encoder;
a space-time block coding (STBC) unit for conducting space-time coding to an output of the QPSK unit;
a preamble code spreading unit for generating a plurality of preamble codes;
a plurality of data frame generating modules for generating a data frame based on the outputs of the STBC unit and the preamble code spreading unit, a pilot code and a cyclic prefix; and
a plurality of transmitting antenna coupled to the corresponding data frame generating modules respectively,
wherein each of the data frame generating modules sends the generated data frame to the receiver via a corresponding transmitting antenna.
2. The MIMO-CDMA wireless communication equipment as claimed in claim 1, wherein each of the data frame generating modules comprises:
a data spreader for spreading the output of the STBC unit, generating a payload data after being added with the cyclic prefix and the pilot codes;
a multiplexer for receiving the payload data and the output of the preamble code spreading unit to output the data frame;
a digitalanalog converter for receiving an output of the multiplexer, and converting it to an analog signal; and
a first radio frequency unit for sending the analog signal generated by the digitalanalog converter to the receiver via a corresponding transmitting antenna.
3. The MIMO-CDMA wireless communication equipment as claimed in claim 2, wherein the data spreader comprises:
a data spreading unit for spreading an output of the QPSK unit;
a cyclic prefix generating unit for receiving an output of the data spreading unit, and outputting the output of the data spreading unit after being added with the cyclic prefix;
a pilot codes generating unit for generating the pilot code; and
an adder for adding the pilot code to the output of the cyclic prefix generating unit to generate the payload data.
4. The MIMO-CDMA wireless communication equipment as claimed in claim 1, wherein the receiver comprises:
a plurality of receiving antennas for receiving the data frame sent by the corresponding transmitting antennas respectively;
a plurality of second radio frequency units coupled to the corresponding receiving antennas respectively, and conducting frequency reducing to the data frame received by the receiving antenna;
a plurality of estimation modules coupled to the corresponding second radio frequency units, for estimating a time parameter, a frequency parameter and a channel parameter of the frequency reduced data frame, and removing the cyclic prefix;
a decision demodulating module for receiving the outputs of the estimation modules, to conduct data spreading and space-time block decoding to the data frame passed through the estimation modules; and
a decoder for receiving the outputs of the decision demodulating module, to revert the original transmission data.
5. The MIMO-CDMA wireless communication equipment as claimed in claim 4, wherein each of the estimation modules comprises:
an analogdigital converter for converting the data frame received by the corresponding second radio frequency unit into a digital signal;
a timefrequency synchronization unit for conducting the time parameter estimating and the space parameter estimating to the digital data frame output by the analogdigital converter based on the preamble codes;
a channel estimation unit for conducting channel estimating to the digital data frame output by the analogdigital converterbased on the preamble codes, and sending the estimation result to the decision demodulating module;
a cyclic prefix removing unit for removing the cyclic prefix in the digital data frame output by the analogdigital converter based on the time parameter and the space parameter, and sending it to the decision demodulating module; and
a phase estimation unit for receiving an output of the cyclic prefix removing unit, to conduct phase estimating to the data frame with the cyclic prefix removed based on the pilot code, and sending the estimation result to the decision demodulating module.
6. The MIMO-CDMA wireless communication equipment as claimed in claim 4, wherein the decision demodulating module comprises:
a decision unit for conducting data spreading and space-time block decoding to an output of the estimation module; and
a QPSK demodulation unit for conducting QPSK demodulating to an output of the decision unit, and sending it to the decoder.
7. A MIMO-CDMA wireless communication equipment, comprising a transmitter and a receiver, wherein the transmitter comprises:
a encoder for receiving a plurality of transmission data and encoding them;
a QPSK unit for conducting QPSK modulating to an output of the encoder;
a space multiplexer for conducting space coding to an output of the QPSK unit;
a preamble code spreading unit for generating a plurality of preamble codes;
a plurality of data frame generating module for generating a data frame based on the outputs of the space multiplexer and the preamble code spreading unit, a pilot code and a cyclic prefix; and
a plurality of transmitting antennas coupled to the corresponding data frame generating modules respectively,
wherein each of the data frame generating modules sends the generated data frame to the receiver via a corresponding transmitting antenna.
8. The MIMO-CDMA wireless communication equipment as claimed in claim 7, wherein each of the data frame generating modules comprises:
a data spreader for spreading the output of the space multiplexer, to generate a payload data after being added with the cyclic prefix and the pilot codes;
a multiplexer for receiving the payload data and the output of the preamble code spreading unit, to output the data frame;
a digitalanalog converter for receiving an output of the multiplexer, and converting it to an analog signal; and
a first radio frequency unit for sending the analog signal generated by the digitalanalog converter to the receiver via a corresponding transmitting antenna.
9. The MIMO-CDMA wireless communication equipment as claimed in claim 8, wherein the data spreader comprises:
a data spreading unit for spreading an output of the QPSK unit;
a cyclic prefix generating unit for receiving an output of the data spreading unit, and outputting the output of the data spreading unit after being added with the cyclic prefix;
a pilot codes generating unit for generating the pilot code; and
an adder for adding the pilot code to the output of the cyclic prefix generating unit to generate the payload data.
10. The MIMO-CDMA wireless communication equipment as claimed in claim 7, wherein the receiver comprises:
a plurality of receiving antennas for receiving the data frame sent by the corresponding transmitting antennas respectively;
a plurality of second radio frequency units coupled to the corresponding receiving antennas respectively, and conducting frequency reducing to the data frame received by the receiving antenna;
a plurality of estimation modules coupled to the corresponding second radio frequency units, for estimating a time parameter, a frequency parameter and a channel parameter of the frequency reduced data frame, and removing the cyclic prefix;
a decision demodulating module for receiving the outputs of the estimation modules, to conduct data spreading and interference eliminating to the data frame passed through the estimation modules; and
a decoder for receiving the outputs of the decision demodulating module, to revert the original transmission data.
11. The MIMO-CDMA wireless communication equipment as claimed in claim 10, wherein each of the estimation modules comprises:
an analogdigital converter for converting the data frame received by the corresponding second radio frequency unit into a digital signal;
a timefrequency synchronization unit for conducting the time parameter estimating and the space parameter estimating to the digital data frame output by the analogdigital converterbased on the preamble codes;
a channel estimation unit for conducting channel estimating to the digital data frame output by the analogdigital converter based on the preamble codes, and sending the estimation result to the decision demodulating module;
a cyclic prefix removing unit for removing the cyclic prefix in the digital data frame output by the analogdigital converter based on the time parameter and the space parameter, and sending it to the decision demodulating module; and
a phase estimation unit for receiving an output of the cyclic prefix removing unit, to conduct phase estimating to the data frame with the cyclic prefix removed based on the pilot code, and sending the estimation result to the decision demodulating module.
12. The MIMO-CDMA wireless communication equipment as claimed in claim 10, wherein the decision demodulating module comprises:
a decision unit for conducting data spreading and interference eliminating to an output of the estimation module; and
a QPSK demodulation unit for conducting QPSK demodulating to an output of the decision unit, and sending it to the decoder.
13. A pre-verifying method for softwarehard ware design of communication system, adapted to verify a communication system having a transmitter end and a receiver end, the pre-verifying method comprising the steps of:
simulating the process of sending a data frame from the transmitter to the receiver with a transceiver algorithm meeting a preset specification, and obtaining a plurality of simulation parameters;
planning the transmitter hardware platform to send out the data frame via an antenna, the transmitter hardware platform having the transmission signal meeting the preset specification;
planning the receiver hardware platform to receive an echo signal of the data frame, and comparing various parameters of the echo signal with the simulation parameters;
verifying whether the result of comparing the various parameters of the echo signal and the simulation parameters is in an desired range;
adjusting the transceiver algorithm if the result of comparing the various parameters of the echo signal and the simulation parameters is not in an desired range; and
converting the transceiver algorithm to a hardware program language format to be written into a programmable module to perform the action of the transmitter and the receiver if the result of comparing the various parameters of the echo signal and the simulation parameters is in an desired range.
14. The pre-verifying for softwarehard ware design of communication system as claimed in claim 13, wherein the simulating step using the receiver algorithm comprises the steps of:
simulating the state of the transmitter, including generating an encoded spreading signal having QPSK modulation by the MATLAB program language, and sampling and pulse shaping the encoded spreading signal;
simulating the channel environment, to simulate the possible situation of the data frame transmitted by the transmitter in real environment, and adding a plurality of channel effects to the data frame, the channel effects including Additive White Gaussian Noise (AWGN) channel effect and Reyleigh Fading channel effect; and
simulating the state of the receiver, to simulate the situation of the receiver receiving the echo signal of the data frame.
15. The pre-verifying for softwarehard ware design of communication system as claimed in claim 14, wherein the step of simulating the channel environment further comprises simulating the oscillating frequency offset effect between the transmitter and the receiver, and simulating the signal propagation delay between the transmitter and the receiver.
16. The pre-verifying for softwarehard ware design of communication system as claimed in claim 13, wherein the step of planning the transmitter hardware platform comprises the step of:
sending the data frame to the receiver via a transmitter radio frequency unit and the antenna, based on the transmission signal stored in a read-only memory(ROM).
17. The pre-verifying for softwarehard ware design of communication system as claimed in claim 13, wherein the step of planning the receiver hardware platform comprises the steps of:
analyzing the echo signal of the data frame with a logic analyzer and MATLAB, to compare it with the simulation parameters; and
displaying the image information on a display through a second universal serial bus(USB).
18. The pre-verifying for softwarehard ware design of communication system as claimed in claim 13, wherein the programmable module is a field programmable gate array (FPGA).