CA2175085A1 - Dual-mode wireless unit with two spread-spectrum frequency bands - Google Patents

Dual-mode wireless unit with two spread-spectrum frequency bands

Info

Publication number
CA2175085A1
CA2175085A1 CA002175085A CA2175085A CA2175085A1 CA 2175085 A1 CA2175085 A1 CA 2175085A1 CA 002175085 A CA002175085 A CA 002175085A CA 2175085 A CA2175085 A CA 2175085A CA 2175085 A1 CA2175085 A1 CA 2175085A1
Authority
CA
Canada
Prior art keywords
frequency
output
synthesizer
range
signal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
CA002175085A
Other languages
French (fr)
Inventor
Robert C. Dixon
Jeffrey S. Vanderpool
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Omnipoint Corp
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of CA2175085A1 publication Critical patent/CA2175085A1/en
Abandoned legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04JMULTIPLEX COMMUNICATION
    • H04J13/00Code division multiplex systems
    • H04J13/10Code generation
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04JMULTIPLEX COMMUNICATION
    • H04J13/00Code division multiplex systems
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B1/00Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/005Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B1/00Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/005Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges
    • H04B1/0053Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges with common antenna for more than one band
    • H04B1/0057Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges with common antenna for more than one band using diplexing or multiplexing filters for selecting the desired band
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B1/00Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/38Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
    • H04B1/40Circuits
    • H04B1/403Circuits using the same oscillator for generating both the transmitter frequency and the receiver local oscillator frequency
    • H04B1/406Circuits using the same oscillator for generating both the transmitter frequency and the receiver local oscillator frequency with more than one transmission mode, e.g. analog and digital modes
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B1/00Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69Spread spectrum techniques
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • H04B7/24Radio transmission systems, i.e. using radiation field for communication between two or more posts
    • H04B7/26Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
    • H04B7/2628Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA]
    • H04B7/2634Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA] for channel frequency control
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00Arrangements for detecting or preventing errors in the information received
    • H04L1/0001Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/10Frequency-modulated carrier systems, i.e. using frequency-shift keying
    • H04L27/12Modulator circuits; Transmitter circuits
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W88/00Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
    • H04W88/02Terminal devices
    • H04W88/06Terminal devices adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Quality & Reliability (AREA)
  • Transmitters (AREA)
  • Transceivers (AREA)
  • Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

The invention provides a dual-band spread-spectrum modulator (101, 103, 105) which uses a single, relatively narrow, synthesizer to serve two operating frequency bands (102, 104). In the lower frequency band, the synthesizer may operate in a high-side injection mode, while in the higher frequency range the synthesizer may operate in a low-side injection mode. In a preferred embodiment, the lower frequency range may comprise about 1850 to 1990 megahertz, while the higher frequency range may comprise about 2400 to 2483.5 megahertz.

Description

Wo 95112925 217 5 ~ ~ ~ PCTIUS94/1246.1 DESCRIPTIQN ~ :
Dual-Mode Wireless Unit With Two S~read-SPectrum Freauençy Bands Backqround of the Invention 1. Pield of the Inventiçn This invention relates to a dual moae wireless unit which uses two spread-spectrum communication bands.
5 2. Descri~tion of Related Art In spread-spectrum modulation in a wireless telephone system, operation in more than one frequency band can be difficult, due to the wide separation between frequency bands. For example, operation in the 900 megahertz and lO laO0 megahertz bands could require a synthesizer capable of covering approximately l, 000 megahertz in frequency spectrum. However, in hand-held equipment such as tele-phones, it is undesirable to use more than one synthesiz-er, or even more than one oscillator, due to increased 15 cost, weight, and related considerations.
Accordingly, it would be advantageous to provide a spread-spectrum system in which a single, relatively narrow, synthesi2er would serve more than one operating f requency band .
20 Summarv of the Invention The invention provides a dual-band spread-spectrum modulator which uses a single, relatively narrow, synthe-sizer to serYe two operating frequency bands. In the lower frequency band, the synthesizer may operate in a 25 high-side injection mode, while in the higher frequency range, the synthesizer may operate in a low-side injection mode. In a preferred embodiment, the lower frequency range may comprise about 1850 to l990 megahertz, while the higher frequency range may comprise about 2400 to 24a3 . 5 3 0 megahertz .

Wo 95/l2925 ~ O C~ PCTIUS94/12464 Brief Descril~tion of the Drawinqs Figure 1 shows a dual-mode spread-spectrum modulator with two frequency bands. s Figure 2 shows a pLU_~' hle frequency generator.
Descri~tion of the Preferred Embodiment Figure 1 shows a dual-mode spread-spectrum modulator with two frequency bands.
A first frequency source 101 may generate a first frequency fl 102, while a second frequency source 103 may generate a second frequency f2 104. The first frequency fl 102 and the second frequency f2 104 may be coupled to a multiplier 105, which may generate a bimodal signal 106 with a frequency distribution over two fres~uency ranges f~
107 and fH 108. In a preferred embodiment, the lower of the two frequencies fL 107 (f~ = fl - f2) may range from about 1850 to l990 megahertz, while the higher of the two frequencies fH 108 ~fH = fl + f2) may range from about 2400 to 2483.5 megahertz. When one of the two frequencies f 1 and f 2, e . g ., f 2 is cho9en between the two ranges, e.g., about 2200 megahertz, the other frequency, e.g., fl may be chosen between about 300 and 440 megahertz.
The bimodal signal 106 may be coupled to a binary encoder 109, for Pn~ofl;ng a data stream 110. The data stream 110, comprising a sequence of data bits 111, may be coupled to the binary encoder 109, which may generate a first fres~uency, e.g., f~ 107, when a data bit 111 in the data stream 110 is a "0" bit, and may generate a second frequency, e.g., fH 108, when a data bit 111 in the data stream 110 is a " 1 " bit .
The present invention also provides for monitoring a frequency in each band (or transmitting to a frequency in each band) at once, because both (fl + f2) and (fl - f2) can be stepped down to the same i ntP ~ ~ te frequency with a single local oscillator. When the ; nt~-rlnP.l; ~te fres~uency is 260 MHz and the local oscillator is set to 2180 MHz, the present invention allows operation at both , . _ _ _ _ _ _ . , .. .. . . _ _ _ _ _ _ _ _ . _ _ _ _ _ _ Wo 95112925 2 ~ 7 ~ PCT/[~S94~1~4~;1 1920 MHz and 2440 M~Iz. When the local oscillator is eet lo MHz greater, the present invention then allows opera-tion at both 1930 MHz and 2450 MHz, i.e., two frequencies each lD MHz greater. Thus for paired frequencies, the 5 present invention allows reception or transmission on either frequency (or both) in the pair.
Figure 2 shows a ~I.,YL hle frequency generator.
A reference frequency signal 201 may be coupled to a multiplier 2D2. The multiplier 2D2 may generate a signal 10 f (s) 203, which may be coupled to a voltage-controlled oscillator (VCO) 204. The VCO 204 may be coupled to an output node 205, which provides an output frequency signal 206, and may also be coupled in a feedback configuration to the multiplier 202 by way of a ~luyl hle divide-by-N
counter 207. The ~L~JyL hle divide-by-N counter 208 may be programmed by a set of control lines 209.
Al t ernat i~re Emho~; m~nt q While preferred embodiments are disclosed herein, many variations are possible which remain within the concept 20 and scope of the invention, and these variations would become clear to one of ordinary skill in the art after perusal of the specification, drawings and claims herein.
For example, information which is encoded for trans-mission is referred to herein as ~data", but it would be 25 clear to those of ordinary skill in the art, after perusal of this application, that these data could comprise data, voice (encoded digitally or otherwise) error-correcting codes, control information, or other signals, and that this would be within the scope and spirit of the inven-30 tion.

Claims (18)

1. A multi-band spread-spectrum communication apparatus comprising a multi-band spread-spectrum modulator comprising:
a dual-band frequency source comprising only one frequency synthesizer, said frequency synthesizer generates a first frequency, said frequency synthesizer having a synthesizer frequency output range, said first frequency falling within said synthesizer frequency output range, a frequency source which generates a second frequency, a multiplier having inputs coupled to said frequency synthesizer and said frequency source, said multiplier having a first and a second output frequency ranges, said first output frequency range defined by a sum of said first frequency and said second frequency, said second output frequency range defined by a difference between said second frequency and said first frequency;
said synthesizer frequency output range is narrower than the range from the lowest frequency of said first or second output frequency range to the highest frequency of said first or second output frequency range; and a binary encoder coupled to said dual-band frequency source.
2. The apparatus of claim 1 wherein said binary encoder comprises a spread-spectrum encoder.
3. The apparatus of claim 1 wherein said first output frequency range spans from 2400 megahertz to 2483.5 megahertz.
4. The apparatus of claim 1 wherein said second output frequency range spans from 1850 megahertz to 1990 megahertz.
5. The apparatus of claim 1 wherein said frequency synthesizer comprises:
a reference frequency signal source;
a programmable divide-by-N counter;
a multiplier having inputs coupled to said programmable divide-by-N counter and said reference frequency signal source; and a voltage-controlled oscillator having an input coupled to said multiplier, said voltage-controlled oscillator having an output coupled to said programmable divide-by-N counter.
6. The apparatus of claim 1 wherein a signal having a frequency in both of said first and second output frequency ranges are transmitted at once.
7. The apparatus of claim 1 further comprising a receiver.
8. The apparatus of claim 7 wherein said receiver comprises a single local oscillator.
9. The apparatus of claim 7 wherein said receiver monitors a frequency in both of said first and second output frequency ranges at once.
10. A method of multi-band spread-spectrum communication comprising the steps of:
generating a first frequency with only one frequency synthesizer;
generating a second frequency;
multiplying said first frequency and said second frequency to generate a signal having a first and a second output frequency ranges, said first output frequency range defined by a sum of said first frequency and said second frequency, said second output frequency range defined by a difference between said second frequency and said first frequency, wherein said frequency synthesizer has a synthesizer frequency output range which is narrower than the range from the lowest frequency of said first or second output frequency range to the highest frequency of said first or second output frequency range; and encoding said signal.
11. The method of claim 10 wherein said encoding step comprises spread-spectrum encoding.
12. The method of claim 10 wherein said first output frequency range spans from 2400 megahertz to 2483.5 megahertz.
13. The method of claim 10 wherein said second output frequency range spans from 1850 megahertz to 1990 megahertz.
14. The method of claim 10 wherein said step of generating a first frequency comprises the steps of:
generating a reference frequency signal;
generating a signal from a programmable divide-by-N
counter which is coupled to a voltage-controlled oscillator;

multiplying said reference signal and said signal from said programmable divide-by-N counter to generate a multiplied signal; and coupling said multiplied signal to said voltage-controlled oscillator to generate said first frequency.
15. The method of claim 10 wherein a signal having a frequency in both of said first and second output frequency ranges are transmitted at once.
16. The method of claim 10 further comprising the step of receiving spread-spectrum signals.
17. The method of 16 wherein said receiving step monitors a frequency in both of said first and second output frequency ranges at once.
18. A spread-spectrum transmitter comprising:
a dual-band frequency source comprising only one frequency synthesizer, said frequency synthesizer generating a first frequency, a frequency source having as an output a second frequency, a multiplier having inputs coupled to said frequency synthesizer and said frequency source, said multiplier having a first and a second output frequency ranges, said first output frequency range defined by a sum of said first frequency and said second frequency, said second output frequency range defined by a difference between said second frequency and said first frequency; and a binary encoder coupled to said dual-band frequency source.
CA002175085A 1993-11-01 1994-10-31 Dual-mode wireless unit with two spread-spectrum frequency bands Abandoned CA2175085A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US14649293A 1993-11-01 1993-11-01
US08/146,492 1993-11-01

Publications (1)

Publication Number Publication Date
CA2175085A1 true CA2175085A1 (en) 1995-05-11

Family

ID=22517619

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002175085A Abandoned CA2175085A1 (en) 1993-11-01 1994-10-31 Dual-mode wireless unit with two spread-spectrum frequency bands

Country Status (6)

Country Link
EP (1) EP0727112A4 (en)
JP (1) JP3692140B2 (en)
KR (1) KR960706234A (en)
CA (1) CA2175085A1 (en)
IL (1) IL111471A (en)
WO (1) WO1995012925A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IL114924A (en) * 1994-08-18 2000-02-17 Omnipoint Corp Multi-land multi-mode communication system

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5537002A (en) * 1978-08-24 1980-03-14 Fujitsu Ltd Fs modulation system
US4435821A (en) * 1981-03-24 1984-03-06 Nippon Electric Co., Ltd. Receiver in a frequency hopping communication system
DE3627045A1 (en) * 1986-08-09 1988-05-11 Quante Fernmeldetechnik Gmbh Alarm system
US4979170A (en) * 1988-01-19 1990-12-18 Qualcomm, Inc. Alternating sequential half duplex communication system
US5079768A (en) * 1990-03-23 1992-01-07 Metricom, Inc. Method for frequency sharing in frequency hopping communications network
AU642571B2 (en) * 1991-01-21 1993-10-21 Sony Corporation Spread spectrum signal receiving apparatus
CA2102914A1 (en) * 1991-05-13 1992-11-26 Robert C. Dixon Dual mode transmitter and receiver

Also Published As

Publication number Publication date
EP0727112A1 (en) 1996-08-21
IL111471A (en) 1998-06-15
WO1995012925A1 (en) 1995-05-11
JP3692140B2 (en) 2005-09-07
JPH09504669A (en) 1997-05-06
KR960706234A (en) 1996-11-08
EP0727112A4 (en) 1998-01-21
IL111471A0 (en) 1994-12-29

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Legal Events

Date Code Title Description
FZDE Discontinued
FZDE Discontinued

Effective date: 20011031