Wireless Communication Systems and Methods

• US 20090185545A1
• Filed: 01/23/2008
• Published: 07/23/2009
• Est. Priority Date: 01/23/2008
• Status: Active Grant

• Current Assignee: Cobblestone Wireless, LLC (Bedrock IP Co., Ltd.)
• Original Assignee: WiLinx Corp.
• Inventors: Mehrnia, Alireza, Darvishzadeh, Mahmoud, Tarighat-Mehrabani, Alireza, Bagheri, Rahim
• Granted Patent: US 7,924,802 B2
• Time in Patent Office: Days
• US Class Current: 370/343
• CPC Class Codes: H04B 1/0067 with one or more circuit blocks in common for different bands
• CPC Class Codes: H04B 1/0483 Transmitters with multiple parallel paths
• CPC Class Codes: H04L 1/0668 Orthogonal systems, e.g. using Alamouti codes
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems

Abstract

Embodiments of the present invention transmit signals simultaneously over a communication channel at different RF center frequencies, and may use a single power amplifier and antenna. In one embodiment the present invention includes a method of transmitting information in a wireless communication channel comprising receiving digital signals having data to be transmitted, converting the signals to analog signals, up-converting each analog signal, combining the up-converted signals, amplifying the combined up-converted signal and transmitting the combined up-converted signal. In one embodiment, the same data is sent over a transmission channel at two different frequencies to improve reliability.

Claims

1. A method of transmitting information in a wireless communication channel comprising:

transmitting first information across a first frequency range using a wireless transmitter, the first frequency range having a first center frequency, a first highest frequency, and a first lowest frequency; and

simultaneously transmitting second information across a second frequency range using the same wireless transmitter, the second frequency range having a second center frequency greater than the first center frequency, a second highest frequency, and a second lowest frequency.

2. The method of claim 1 wherein frequency difference between the first center frequency and the second center frequency is greater than the sum of one-half the first frequency range and one-half the second frequency range.

3. The method of claim 1 wherein the first and second information are transmitted using the same power amplifier in said wireless transmitter.

4. The method of claim 3 wherein the bandwidth of said power amplifier is greater than the difference between the first lowest frequency and the second highest frequency.

5. The method of claim 1 further comprising concurrently changing the first center frequency to a third center frequency and the second center frequency to a fourth center frequency, wherein the fourth center frequency is greater than the third center frequency, and wherein the first center frequency changes by at least the first frequency range and the second center frequency changes by at least the second frequency range, and wherein the bandwidth of said power amplifier is greater than the difference between the first lowest frequency and the second highest frequency for the changed first and second center frequencies.

6. The method of claim 1 wherein the first information corresponds to a first wireless protocol and the second information corresponds to a second wireless protocol.

7. The method of claim 1 wherein the first information and the second information are the same data transmitted across two different frequencies.

8. The method of claim 1 wherein the first information and the second information are from the same data stream.

9. The method of claim 1 wherein first information and second information comprise a plurality of OFDM symbols, wherein a first symbol is transmitted during a first time slot across the first frequency range and a second symbol is transmitted during the first time slot across the second frequency range, and wherein a third symbol is transmitted during a second time slot across the first frequency range and a fourth symbol is transmitted during the second time slot across a second frequency range.

10. A method of transmitting information in a wireless communication channel comprising:

receiving a first digital signal comprising first data to be transmitted;

receiving a second digital signal comprising second data to be transmitted;

converting the first digital signal into a first analog signal using a first digital-to-analog converter, the first analog signal carrying the first data across a first frequency range;

converting the second digital signal into a second analog signal using a second digital-to-analog converter, the second analog signal carrying the second data across a second frequency range;

up-converting the first analog signal to a first RF center frequency to produce a first up-converted analog signal, wherein the first up-converted analog signal comprises a first up-converted frequency range from the first RF center frequency minus one-half the first frequency range to the first RF center frequency plus one-half the first frequency range;

up-converting the second analog signal to a second RF center frequency greater than the first center RF frequency to produce a second up-converted analog signal, wherein the second up-converted analog signal comprises a second up-converted frequency range from the second RF center frequency minus one-half the second frequency range to the second RF center frequency plus one-half the second frequency range, and wherein a frequency difference between the first RF center frequency and the second RF center frequency is greater than the sum of one-half the first frequency range and one-half the second frequency range;

combining the first up-converted analog signal and the second up-converted analog signal to produce a combined up-converted signal;

amplifying the combined up-converted signal in a power amplifier resulting in an amplified combined up-converted signal; and

transmitting the amplified combined up-converted signal on a first antenna, wherein the bandwidth of said power amplifier is greater than the difference between a lowest frequency in the first up-converted frequency range and a highest frequency in the second up-converted frequency range.

11. The method of claim 10 further comprising changing the first and second RF center frequencies, and in accordance therewith, up-converting the first analog signals to the changed first and second RF center frequencies, wherein the first RF center frequency changes by at least the first frequency range and the second RF center frequency changes by at least the second frequency range.

12. The method of claim 11 wherein the first and second RF center frequencies are changed concurrently.

13. The method of claim 10 wherein the first digital signal is encoded using a first wireless protocol and the second digital signal is encoded using a second wireless protocol.

14. The method of claim 10 wherein the second data is the same as the first data, the method further comprising:

receiving the transmitted signal on a second antenna;

amplifying the received signal in a low noise amplifier resulting in an amplified received up-converted signal, wherein the bandwidth of said low noise amplifier is greater than the difference between the lowest frequency in the first up-converted frequency range and the highest frequency in the second up-converted frequency range;

down-converting the amplified received up-converted signal using a first down-converter and a signal corresponding to the first RF center frequency to produce a fourth analog signal corresponding to the first analog signal; and

down-converting the amplified received up-converted analog signal using a second down-converter and a signal corresponding to the second RF center frequency to produce a fifth analog signal corresponding to the second analog signal.

15. The method of claim 12 further comprising:

filtering the fourth analog signal using a third filter and filtering the fifth analog signal using a fourth filter; and

converting the filtered fourth analog signal into a third digital signal using a first analog-to-digital converter and converting the filtered fifth analog signal into a fourth digital signal using a second analog-to-digital converter; and

combining the third and fourth digital signals to receive data corresponding to the first data.

16. The method of claim 12 further comprising:

combining the fourth and fifth analog signals resulting in a sixth signal; and

converting the sixth signal into a third digital signal using a first analog-to-digital converter, and in accordance therewith, receiving data corresponding to the first data.

17. A wireless communication system comprising:

a baseband digital system for providing a first digital signal comprising a first data to be transmitted and a second digital signal comprising a second data to be transmitted;

a first digital-to-analog converter for receiving the first digital signal and converting the first digital signal into a first analog signal, the first analog signal carrying the first data across a first frequency range;

a second digital-to-analog converter for receiving the second digital signal and converting the second digital signal into a second analog signal, the second analog signal carrying the second data across a second frequency range;

a first up-converter circuit having a first input coupled to receive the first analog signal and a second input coupled to receive a first modulation signal having a first RF frequency, wherein the first up-converter outputs a first up-converted analog signal comprising a first up-converted frequency range from the first RF frequency minus one-half the first frequency range to the first RF frequency plus one-half the first frequency range;

a second up-converter circuit having a first input coupled to receive the second analog signal and a second input coupled to receive a second modulation signal having a second RF frequency, wherein the second up-converter outputs a second up-converted analog signal comprising a second up-converted frequency range from the second RF frequency minus one-half the second frequency range to the second RF frequency plus one-half the second frequency range, and wherein frequency difference between the first RF frequency and the second RF frequency is greater than the sum of one-half the first frequency range and one-half the second frequency range; and

a power amplifier coupled to receive the first and second up-converted analog signals, wherein the bandwidth of the power amplifier is greater than the difference between a lowest frequency in the first up-converted frequency range and a highest frequency in the second up-converted frequency range.

18. The communication system of claim 17 wherein the first RF frequency and the second RF frequency change within the bandwidth of the power amplifier.

19. The communication system of claim 18 wherein the first RF frequency and the second RF frequency change concurrently.

20. The communication system of claim 18 wherein the first RF frequency and the second RF frequency change periodically.

21. The communication system of claim 17 wherein the first data of the first digital signal is encoded using a first wireless protocol and the first data of the second digital signal is encoded using a second wireless protocol.

22. The communication system of claim 17 wherein the second data corresponds to the first data and wherein the power amplifier outputs a third up-converted signal comprising the up-converted first analog signal and the up-converted second analog signal.

23. The communication system of claim 17 wherein first and second data to be transmitted comprise a plurality of OFDM symbols, wherein a first symbol is transmitted during a first time slot across the first up-converted frequency range and a second symbol is transmitted during the first time slot across the second up-converted frequency range, and wherein a third symbol is transmitted during a second time slot across the first up-converted frequency range and a fourth symbol is transmitted during the second time slot across a second up-converted frequency range.

24. An electronic circuit comprising:

a first down-converter circuit having a first input coupled to receive a first up-converted signal, a second input coupled to receive a first demodulation signal having a first RF frequency, and an output, wherein the first down-converter circuit outputs a first down-converted signal on the first down-converter output;

a second down-converter circuit having a first input coupled to receive the first up-converted signal, a second input coupled to receive a second demodulation signal having a second RF frequency different than the first RF frequency, and an output, wherein the second down-converter outputs a second down-converted signal on the second down-converter output, wherein the first up-converted signal comprises a first signal modulated at the first RF frequency and a second signal modulated at the second RF frequency; and

a filter having an input coupled to the output of the first down-converter and the output of the second down-converter, and in accordance therewith, the filter receives the first and second down-converted signals.

25. The communication system of claim 24 wherein first signal has a first frequency range and the second signal has a second frequency range, and wherein the frequency difference between the first RF frequency and the second RF frequency is greater than the sum of one-half the first frequency range and one-half the second frequency range.