1. A radio frequency (RF) receiver for a code division multiple access (CDMA) mobile communication base station system, which has a plurality of receive blocks receiving RF signals via a plurality of antennas, and a plurality of frequency allocation (FA)-based channel cards, the RF receiver comprising:
an analog down-converting means for down-converting multi-FA RF signals on the respective reception paths output from the plural receive blocks to intermediate frequency (IF) signals; and
a digital down-converting means for converting the IF signals of 3 FA’s on the respective reception paths output from the analog down-converting means to digital signals by reception paths, dividing the digital signals into in-phase (I) and quadrature (Q) channels, converting the divided digital signals into IQ channel baseband signals, and outputting the FA-based IQ channel baseband signals to the channel cards corresponding to the respective FA’s, wherein the analog down converting means comprises:
a local oscillator on the individual reception paths for generating a local frequency;
a mixer on the individual reception paths for mixing the local frequency generated from the local oscillator with the multi-PA RF signals on the individual reception paths output from the plural receive blocks to generate multi-FA IF signals on the individual reception paths; and
an SAW filter on the individual reception paths for limiting the band of the multi-FA IF signals on the individual reception paths output from the individual mixer to the bandpass of a bandwidth corresponding to the multi-FA bandwidth.
2. The RE receiver as claimed in claim 1, wherein the multiple PA’s are 3 PA’s, the IF frequency on the individual reception paths of \u201c0\u201d and \u201c1\u201d is 70 MHz, and the bandwidth of the SAW filter is 3.75 MHz corresponding to the 3 FA’s.
3. A radio frequency (RF) receiver for a code division multiple access (CDMA) mobile communication base station system, which has a plurality of receive blocks receiving RF signals via a plurality of antennas, and a plurality of frequency allocation (FA) based channel cards, the RF receiver comprising:
an analog down-converting means for down-converting multi-FA RF signals on the respective reception paths output from the plural receive blocks to intermediate frequency (IF) signals; and
a digital down-converting means for converting the IF signals of 3 FA’s on the respective reception paths output from the analog down-converting means to digital signals by reception paths, dividing the digital signals into in-phase (I) and quadrature (Q) channels, converting the divided digital signals into IQ channel baseband signals, and outputting the FA-based IQ channel baseband signals to the channel cards corresponding to the respective FA’s, wherein the digital down-converting means comprises:
an analog-to-digital converter on the individual reception paths for converting the IF signals output from the analog down-converters to digital signals;
a FA-based digital unit on the individual reception paths for dividing the digital signals output from each analog-to-digital converter into the FA-based IQ channels on the individual reception paths to perform QPSK, demodulation and down-converting the IQ channel digital signals to IQ channel baseband signals; and
a multiplexer for multiplexing the reception paths and the IQ channel baseband signals output from the FA-based digital unit and generating the multiplexed digital signals to the channel cards corresponding to the respective FA’s.
4. The RE receiver as claimed in claim 3, wherein the digital unit comprises:
a first reception path 0FA digital unit for converting the digital signals output from the analog-to-digital converter corresponding to the first reception path to the IQ channel baseband signals assigned to 0FA;
a first reception path 1FA digital unit for converting the digital signals output from the analog-to-digital converter corresponding to the first reception path to the IQ channel baseband signals assigned to 1FA;
a first reception path 2FA digital unit for converting the digital signals output from the analog-to-digital converter corresponding to the first reception path to the IQ channel baseband signals assigned to 2FA;
a second reception path 0FA digital unit for converting the digital signals output from the analog-to-digital converter corresponding to the second reception path to the IQ channel baseband signals assigned to 0FA;
a second reception path 1FA digital unit for converting the digital signals output from the analog-to-digital converter corresponding to the second reception path to the IQ channel baseband signals assigned to 1FA; and
a second reception path 2FA digital unit for converting the digital signals output from the analog-to-digital converter corresponding to the second reception path to the IQ channel baseband signals assigned to 2FA.
5. The RF receiver as claimed in claim 3, wherein the individual FA-based digital unit comprises:
a channel divider for dividing the digital signals output from the analog-to-digital converter on the corresponding reception paths into I and Q channels for QPSK demodulation at the digital unit on the respective reception paths;
a local oscillator for generating a local frequency;
a mixer for mixing the local frequency generated from the local oscillator with the divided IQ channel signals to convert the IQ channel signals to IQ channel baseband signals; and
a digital FIR filter for band-pass filtering the respective reception paths and the FA-based IQ channel baseband signals output from the mixer and generating the band-limited baseband signals to the multiplexer.
6. The RF receiver as claimed in claim 3, wherein the multiplexer multiplexes:
the IQ channel baseband signals output from the first reception path 0FA digital unit and the IQ channel baseband signals output from the second reception path 0FA digital unit;
the IQ channel baseband signals output from the first reception path 1FA digital unit and the IQ channel baseband signals output from the second reception path 1FA digital unit; and
the IQ channel baseband signals output from the first reception path 2FA digital unit and the IQ channel baseband signals output from the second reception path 2FA digital unit, and
generates the multiplexed signals to the channel cards corresponding to the respective FA’s.
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 silicone rubber sponge composition comprising
(A) 100 parts by weight organopolysiloxane gum described by average structural unit RaSiO(4a)2, where R is a monovalent hydrocarbon group or haloalkyl and a is 1.8 to 2.3 and having a viscosity at 25 C. of 1,000,000 mPas or above,
(B) 1 to 400 parts by weight inorganic filler,
(C) 0.01 to 50 parts by weight hollow thermoplastic resin particles,
(D) 0.01 to 10 parts by weight water-in-oil emulsion with silicone oil as an oil phase, and
(E) a curing agent in an amount sufficient to cure the composition.
2. The silicone rubber sponge composition according to claim 1, where component (C) comprises thermoplastic resin shells having a softening point of from 40 C. to 200 C. and having a gas enclosed therein.
3. The silicone rubber sponge composition according to claim 1, where the thermoplastic resin of component (C) is selected from the group consisting of silicone resin, acrylic resin, and polycarbonate resin.
4. The silicone rubber sponge composition according to claim 1, where component (A) has a viscosity at 25 C. of 5,000,000 mpas or above.
5. The silicone rubber sponge composition according to claim 1 comprising 1 to 100 parts by weight reinforcing filler as component (B).
6. The silicone rubber sponge composition according to claim 1, where component (C) has a softening point of 60 to 180 C. and an average particle size of 1 to 50 m.
7. The silicone rubber sponge composition according to claim 1, where component (C) comprises 0.1 to 40 parts by weight per 100 parts by weight of component (A).
8. The silicone rubber sponge composition according to claim 1, where the silicone oil of component (D) is a trimethylsilyl endblock dimethylpolysiloxane oil.
9. The silicone rubber sponge composition according to claim 1, where the silicone oil of component (D) is a dimethylhydroxysilyl endblocked dimethylpolysiloxane oil.
10. The silicone rubber sponge composition according to claim 1, where the silicone oil of component (D) has a viscosity at 25 C. of from 10 to 100,000 mPas.
11. The silicone rubber sponge composition according to claim 1 comprising from 0.1 to 5 parts by weight component (D) per 100 parts by weight of component (A).
12. A silicone rubber sponge article comprising the reaction product of a composition comprising
(A) 100 parts by weight organopolysiloxane gum described by average structural unit RaSiO(4a)2, where R is a monovalent hydrocarbon group or haloalkyl and a is 1.8 to 2.3 and having a viscosity at 25 C. of 1,000,000 mPas or above,
(B) 1 to 400 parts by weight inorganic filler,
(C) 0.01 to 50 parts by weight hollow thermoplastic resin particles,
(D) 0.01 to 10 parts by weight water-in-oil emulsion with silicone oil as an oil phase, and
(E) a curing agent in an amount sufficient to cure the composition.
13. A silicone rubber sponge article according to claim 12, where the article is selected from the group consisting of a sheet, tube, gasket, and sheath material for a roller.
14. A silicone rubber sponge article according to claim 12 prepared by a process selected from the group consisting of extrusion molding and compression molding.
15. A process for making a silicone rubber sponge article comprising curing a composition comprising
(A) 100 parts by weight organopolysiloxane gum described by average structural unit RaSiO(4a)2, where R is a monovalent hydrocarbon group or haloalkyl and a is 1.8 to 2.3 and having a viscosity at 25 C. of 1,000,000 mPas or above,
(B) 1 to 400 parts by weight inorganic filler,
(C) 0.01 to 50 parts by weight hollow thermoplastic resin particles,
(D) 0.01 to 10 parts by weight water-in-oil emulsion with silicone oil as an oil phase, and
(E) a curing agent in an amount sufficient to cure the composition, by heating at a temperature equal to or above the softening point of component (C).