MIMO-based multiuser OFDM multiband for ultra wideband communications

• US 7,263,133 B1
• Filed: 09/02/2003
• Issued: 08/28/2007
• Est. Priority Date: 09/02/2003
• Status: Active Grant

• Current Assignee: MIMO Research, LLC
• Original Assignee: George J. Miao
• Inventors: Miao, George J.
• Primary Examiner(s): Fan, Chieh M.
• Assistant Examiner(s): Pathak, Sudhanshu C.
• Application Number:
  US10/653,651
• Time in Patent Office: 1,456 Days
• Field of Search: 375/146, 375/267, 375/349, 375/130, 370/208, 714/755
• US Class Current: 375/267
• CPC Class Codes: H04B 1/71632 Signal aspects H04B1/7172 and H04B1/7176 take precedence
• CPC Class Codes: H04B 1/719 Interference-related aspects
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04L 5/0044 allocation of payload

Abstract

A MIMO-based multiuser OFDM multiband of UWB communications is presented to meet FCC emission limitations for indoor UWB operations. The present UWB system divides a single UWB frequency band of 7.5 GHz into eleven frequency bands as a multiband. Each frequency band has 650-MHz frequency bandwidth, uses an OFDM with multicarrier, and employs different modulations. The present UWB system can be programmable not only to transmit different data rates in a relatively longer distance but also to avoid interference with other devices by controlling the multiband and/or some of the multicarrier within each of the OFDM. The present UWB system can transmit a very high data rate up to 11 Gbps approximately.

Claims

1. A multiple-input multiple-output (MIMO)-based multiuser orthogonal frequency division multiplex (OFDM) multiband of ultra wideband (UWB) base station communication transmitter comprising:

p user bitstream coupled to p convolution encoders, where p is an integer and greater than 1;

said p convolution encoders coupled to p interleavers;

p outputs of said p interleavers spread out by p user keys to form an encoded sequence by a sum over a block;

each of said p user keys is a unique and orthogonal each other;

said sum over a block coupled to a polyphase-based multiband;

wherein said polyphase-based multiband includes a random access memory (RAM) bank with a length size of N for storing serial input data and P RAM banks with a length size of N/P for storing parallel output data, where N, and P are integers and greater than 1, N is greater than P, and N/P is an integer;

said polyphase-based multiband coupled to k serial-to-parallel (S/P), where k is an integer and greater than 1;

said k S/P coupled to k inverse fast Fourier transforms (IFFTs);

said k IFFTs coupled to k guards;

said k guards coupled to k filtering and spreading units;

said k filtering and spreading units coupled to a MIMO-based multiband and multicarrier radio frequency (RF) unit; and

said MIMO-based multiband and multicarrier RF unit coupled to k antennas.

2. The MIMO-based multiuser OFDM multiband of UWB base station communication transmitter of claim 1 wherein polyphase-based multiband can produce P parallel data sequences with a data rate of N/P from a serial data sequence with a data rate of N, where N, and P are integers and greater than 1, N is greater than P, and N/P is an integer.

3. The MIMO-based multiuser OFDM multiband of UWB base station communication transmitter of claim 1 wherein each of said k filtering and spreading units further comprises:

a dual-switch with N inputs and two outputs, where N is an integer and greater than 1;

said two outputs of the dual-switch spread out by a multiband spreading via two exclusive-OR (XOR) modules;

said two XOR modules coupled to two transmitter shaped filters followed by two digital-to-analog (D/A) converters; and

said two D/A converters coupled to two analog reconstruction filters.

4. The MIMO-based multiuser OFDM multiband of UWB base station communication transmitter of claim 3 wherein said multiband spreading produces an orthogonal sequence for each of frequency bands.

5. The MIMO-based multiuser OFDM multiband of UWB base station communication transmitter of claim 4 wherein signals of frequency bands are orthogonal each other.

6. The MIMO-based multiuser OFDM multiband of UWB base station communication transmitter of claim 1 wherein said MIMO-based multiband modulation and multicarrier RF unit further includes k multiband modulations, k additions followed by k analog bandpass filters, and each of the k multiband modulations coupled to all of the k additions, where k is an integer and greater than 1.

7. The MIMO-based multiuser OFDM multiband of UWB base station communication transmitter of claim 6 wherein the k multiband modulations equivalently contain one of the modulations including binary phase-shifted keying (BPSK), quadrature phase-shifted keying (QPSK) or 16-ary quadrature-amplitude-modulation (16-QAM).

8. The MIMO-based multiuser OFDM multiband of UWB base station communication transmitter of claim 1 wherein said MIMO-based multiband and multicarrier RF unit coupled to said k antennas is used to enhance UWB signals quality and\or increase UWB transmitting distance.

9. The MIMO-based multiuser OFDM multiband of UWB base station communication transmitter of claim 3 wherein each of said multiband spreading has two outputs producing two exact sequences.

10. A multiple-input multiple-output (MIMO)-based multiuser orthogonal frequency division multiplex (OFDM) multiband of ultra wideband (UWB) mobile communication receiver comprising:

two antennas;

a two-antenna based multiband radio frequency (RF) receiver unit;

said two-antenna based multiband RF receiver unit coupled to a combination section including an analog-to-digital (A/D) unit, a digital receiver filter unit, and a multiband-despreading unit;

said A/D unit further including 2k A/D converters with the same sampling rate and resolution, where k is an integer and greater than 1;

said digital receiver filter unit further having 2k digital receiver filters;

said 2k A/D converters coupled to 2k digital receiver filters;

said multiband-despreading unit further comprising k multiband spreading;

each of said k multiband spreading spreads out two outputs of the said digital receiver filters via two exclusive-OR (XOR) modules;

said combination section coupled to a time-domain equalizer (TEQ) unit, which is M inputs and outputs where M is an integer and greater than 1;

said TEQ unit coupled to k serial-to-parallel (S/P) followed by k guard removings that are connected to k fast Fourier transforms (FFTs);

each of said k FFTs having 2N inputs, N outputs, N disable-point, where N is an integer and greater than 1;

said k FFTs coupled to k frequency-domain equalizer (FEQ) units that are connected with k parallel-to-serial (P/S);

each of said FEQ units further including Q equalizers, Q decision detectors, Q subtractors, and an adaptive algorithm, where Q is an integer and greater than 1;

said k P/S coupled to a polyphase-based demultiband; and

said polyphase-based demultiband coupled to a despreading, deinterleaver, and decoding unit.

11. The MIMO-based multiuser OFDM multiband of UWB mobile communication receiver of claim 10 wherein said 2k digital receiver filters have the same magnitude response and linear phase with the same number of filter coefficients, where k is an integer and greater than 1.

12. The MIMO-based multiuser OFDM multiband of UWB mobile communication receiver of claim 10 wherein said two-antenna based multiband RF receiver unit further includes two low-noise amplifier (LNA), two automatic gain control (AGC), two analog bandpass filters, an addition, eleven multiband down converters and demodulations.

13. The MIMO-based multiuser OFDM multiband of UWB mobile communication receiver of claim 10 wherein said k multiband despreading generate k unique but different orthogonal despreading sequences for each of the frequency bands, where k is an integer and greater than 1.

14. The MIMO-based multiuser OFDM multiband of UWB mobile communication receiver of claim 10 wherein said polyphase-based demultiband further includes a random access memory (RAM) bank with a length size of N, and P parallel RAM banks with a length size of N/P, where N and P are integers and greater than 1 and N/P is an integer.

15. The MIMO-based multiuser OFDM multiband of UWB mobile communication receiver of claim 14 wherein said polyphase-based demultiband produces a serial output sequence with a data rate of N from P parallel input sequences with a data rate of N/P, where N and P are integers and greater than 1 and N/P is an integer.

16. A multiple-input multiple-output (MIMO)-based multiuser orthogonal frequency division multiplex (OFDM) multiband of ultra wideband (UWB) communication system comprising:

a MIMO-based multiuser OFDM multiband of UWB base station communication transmitter and receiver;

said MIMO-based multiuser OFDM multiband of UWB base station communication transmitter and receiver having N base station antennas, wherein said N base station antennas of the MIMO-based multiuser OFDM multiband of UWB base station communication transmitter and receiver are programmable and further wherein the fourth and/or fifth base station antennas can be turned off to avoid interference with wireless local area network (WLAN) devices, where N is an integer and greater than 5;

said N base station antennas are controllable;

said MIMO-based multiuser OFDM multiband of UWB base station communication transmitter and receiver coupled to an UWB network interface unit;

said UWB network interface unit coupled to an UWB network;

P MIMO-based OFDM multiband of UWB mobile communication transmitters and receivers, where P is an integer and greater than 1;

each of said P MIMO-based OFDM multiband of UWB mobile communication transmitters and receivers having Q mobile station antennas, where Q is an integer and greater than 1;

said Q mobile station antennas are controllable;

the number of said N base station antennas is greater than the number of said Q mobile station antennas; and

said P MIMO-based OFDM multiband of UWB mobile communication transmitters and receivers communicate with said MIMO-based multiuser OFDM multiband of UWB base station communication transmitter and receiver via a MIMO channel link.

17. The MIMO-based multiuser OFDM multiband of UWB communication system of claim 16 wherein said Q mobile station antennas of each of the MIMO-based OFDM multiband of UWB mobile communication transmitters and receivers are independent, identical and programmable antennas, where Q is an integer and greater than 1.