Low cost broadband wireless communication system
This present invention includes an indoor unit (IDU) and compact outdoor unit (ODU) having an intermediate frequency/modem circuit, millimeter wave transceiver circuit, and digital interface between the IDU and the ODU capable of up to about 100 MBps data rate over at least about a 300 meter cable. The system uses a conversion to the polar coordinate system completes calculations in the polar coordinate system, reducing the computational requirements, and therefore, the size and cost of the system.
1 . A system for millimeter wave communications, which comprises:
an indoor unit;
an outdoor unit in communication with the indoor unit and receiving and/or transmitting millimeter wave communications signals and including an intermediate frequency/modem circuit that processes the millimeter wave communications signals using a polar coordinate system of calculations.
2 . A system according to claim 1 , and further comprising a single coaxial connection extending between the indoor unit and outdoor unit.
3 . A system according to claim 1 , wherein said outdoor unit comprises a millimeter wave transceiver board comprising microwave monolithic integrated circuit (MMIC) chips.
4 . A system according to claim 1 , wherein said outdoor unit further comprises a housing and an intermediate frequency/modem board, a frequency synthesizer board and a millimeter wave transceiver board contained within the housing.
5 . A system according to claim 4 , wherein said millimeter wave transceiver board comprises a ceramic board.
6 . A system according to claim 1 , and further comprising a millimeter wave transceiver board comprising a transmit circuit chain, a receive circuit chain and a local oscillator circuit chain.
7 . A system according to claim 6 , and further comprising a mixer circuit operatively connected to said transmit circuit chain for down converting millimeter wave transmitter coupled signals back to an intermediate frequency.
8 . A system according to claim 1 , wherein said intermediate frequency/modem circuit further comprises a modulator circuit and demodulator circuit that support quadrature phase shift keying (QPSK) modulation or quadrature amplitude modulation (QAM).
9 . A system according to claim 1 , wherein said intermediate frequency/modem circuit comprises a multiplexer/demultiplexer circuit that separates transmit, receive, and command and control data that had been time multiplexed together.
10 . A system according to claim 1 , wherein said outdoor unit further comprises a processor that computes predistortion coefficients used to correct amplifier nonlinearity based on detected power and phase.
11 . A system according to claim 1 , wherein said intermediate frequency/modem circuit is operative for transmitting and/or receiving a packet of data having a preamble that is independent of data modulation.
12 . A system according to claim 11 , wherein the preamble has a first stop symbol that corresponds to an absence of a carrier or zero amplitude and a second start symbol that is fixed in amplitude and phase for allowing amplitude and phase offset calibration.
13 . An outdoor unit for millimeter wave communication, which comprises:
a millimeter wave transceiver board comprising microwave monolithic integrated circuit (MMIC) chips; and
an intermediate frequency/modem board operable with the millimeter wave transceiver board and operable for processing millimeter wave communications signals using a polar coordinate system of calculations.
14 . An outdoor unit according to claim 13 , and comprising a connector adapted for connecting to a single coaxial connection for connecting to an indoor unit.
15 . An outdoor unit according to claim 13 , and further comprising a housing in which the millimeter wave transceiver board and intermediate frequency/modem board are contained.
16 . An outdoor unit according to claim 13 , wherein said millimeter wave transceiver board comprises a ceramic board.
17 . An outdoor unit according to claim 13 , wherein said millimeter wave transceiver board comprises a transmit circuit chain, a receive circuit chain and a local oscillator circuit chain.
18 . An outdoor unit according to claim 17 , wherein said millimeter wave transceiver board comprises a mixer circuit operatively connected to said transmit circuit chain for down converting millimeter wave transmitter coupled signals back to an intermediate frequency.
19 . An outdoor unit according to claim 13 , wherein said intermediate frequency/modem board further comprises a modulator circuit and a demodulator circuit that support quadrature phase shift keying (QPSK) modulation or quadrature amplitude modulation (QAM).
20 . An outdoor unit according to claim 13 , wherein said intermediate frequency/modem board further comprises a multiplexer/demultiplexer circuit that separates transmit, receive, and command and control data that had been time multiplexed together.
21 . An outdoor unit according to claim 13 , and further comprising a frequency synthesizer board operable to generate local oscillator signals for MMIC chips on the millimeter wave transceiver board.
22 . An outdoor unit for millimeter wave communications, which comprises:
a housing;
a millimeter wave transceiver board contained in the housing and comprising microwave monolithic integrated circuit (MMIC) chips;
an intermediate frequency/modem board contained within the housing and operable with the millimeter wave transceiver board for processing millimeter wave communications signals; and
a circuit operable for detecting power and phase and computing predistortion coefficients for correcting any amplifier nonlinearity.
23 . An outdoor unit according to claim 22 , and further comprising a connector adapted for connecting to a single coaxial connection and to an indoor unit.
24 . An outdoor unit according to claim 22 , wherein said millimeter wave transceiver board comprises a ceramic board.
25 . An outdoor unit according to claim 22 , wherein said millimeter wave transceiver board comprises a transmit circuit chain, a receive circuit chain and a local oscillator circuit chain.
26 . An outdoor unit according to claim 25 , wherein said millimeter wave transceiver board comprises a mixer circuit operatively connected to said transmit circuit chain for down converting millimeter wave transmitter coupled signals back to an intermediate frequency.
27 . An outdoor unit according to claim 22 , wherein said intermediate frequency/modem board further comprises a modulator circuit and a demodulator circuit that support quadrature phase shift keying (QPSK) modulation or quadrature amplitude modulation (QAM).
28 . An outdoor unit according to claim 22 , wherein said intermediate frequency/modem board further comprises a multiplexer/demultiplexer circuit that separates transmit, receive, and command and control data that had been time multiplexed together.
29 . An outdoor unit according to claim 22 , and further comprising a frequency synthesizer board operable to generate local oscillator signals for MMIC chips on the millimeter wave transceiver board.
30 . A method for millimeter wave communications using an outdoor unit and indoor unit in communication with each other, which comprises:
transmitting and/or receiving a millimeter wave communications signal within an intermediate frequency/modem circuit that is operative for communicating with a millimeter wave transceiver circuit; and
processing the communications signal within the intermediate frequency/modem circuit using a polar coordinate system of calculations.
31 . A method according to claim 30 , which further comprises transmitting a packet of data having preamble that is independent of data modulation.
32 . A method according to claim 31 , which further comprises modulating payload data with either quadrature phase shift keying or quadrature amplitude modulation.
33 . A method according to claim 31 , wherein the preamble has a first stop symbol that corresponds to an absence of a carrier or zero amplitude and a second start symbol that is fixed in amplitude and phase for allowing amplitude and phase offset calibration.
34 . A method according to claim 33 , which further comprises calibrating any Cartesian offsets by the stop symbol.
35 . A method according to claim 33 , which further comprises determining angular rotation of a symbol phase and predicting average phase offset for a duration of a frame by consecutive frame-to-frame phase offsets.
36 . A method according to claim 33 , which further comprises calibrating the timing of symbols during a preamble and maintaining during the symbol frame by the clocking.
37 . A method according to claim 33 , which further comprises transmitting a continuous signal at a fixed amplitude but at a continuously changing phase.
38 . A method according to claim 37 , which further comprises following an angular rotation in the positive direction with an angular rotation in the negative direction.
39 . A method according to claim 30 , which further comprises duplicating forward error correction blocks at least once to allow errors in a serial coaxial connection at the indoor unit and outdoor unit to be isolated from errors in the intermediate frequency/modem circuit.
40 . A method according to claim 30 , which further comprises communicating between the indoor unit and outdoor unit by inserting digital command data into the payload data.
41 . A method according to claim 40 , which further comprises establishing a fixed reference value as a zero value and a one value as offset either positive or negative from the reference level.
42 . A method according to claim 30 , which further comprises transferring signals along a single coaxial connection extending between the outdoor unit and indoor unit.
43 . A method according to claim 30 , which further comprises detecting power and phase and computing any predistortion coefficients used in the intermediate frequency/modem circuit for correcting amplifier nonlinearity.
44 . A method according to claim 30 , wherein the millimeter wave transceiver circuit includes a transmit circuit chain, a receive circuit chain and a local oscillator circuit chain.
45 . A method according to claim 44 , which further comprises coupling an output from the transmit circuit chain to a mixer circuit for down converting millimeter wave transmitter coupled signal back to an intermediate frequency.