|Publication number||US7835427 B1|
|Application number||US 11/731,798|
|Publication date||Nov 16, 2010|
|Filing date||Mar 30, 2007|
|Priority date||Mar 30, 2007|
|Publication number||11731798, 731798, US 7835427 B1, US 7835427B1, US-B1-7835427, US7835427 B1, US7835427B1|
|Inventors||Carlos J. Chavez, Robert Joseph Frank, Michael R. Vagher, Carlen R. Welty|
|Original Assignee||Rockwell Collins, Inc.|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (49), Referenced by (2), Classifications (8), Legal Events (2)|
|External Links: USPTO, USPTO Assignment, Espacenet|
The present invention relates generally to the field of frequency hopping spread spectrum radio transmission. More particularly, the present invention relates to a system and method for simultaneous transmission and reception of signals during frequency hopping spread spectrum radio transmission.
Frequency hopping spread spectrum (FHSS) is a method of transmitting radio signals by rapidly switching a carrier among many frequency channels using a pseudorandom sequence known to both transmitter and receiver. Spread spectrum signals are highly resistant to noise and interference, are difficult to intercept, and can share a frequency band with many types of conventional transmissions with minimal interference.
In a frequency hopping system, a transmitter “hops” between available frequencies according to a specified algorithm, which can be either random or preplanned. The transmitter operates in synchronization with a receiver, which remains tuned to the same center frequency as the transmitter. A short burst of data is transmitted on a narrow frequency band. Then, the transmitter tunes to another frequency and transmits again. The receiver thus is capable of hopping its frequency over a given bandwidth several times a second, receiving on one frequency for a certain period of time, then hopping to another frequency and receiving again. Frequency hopping requires a much wider bandwidth than is needed to transmit the same information using only one carrier frequency.
During transmission, a frequency hopping transceiver generates a signal that may be several orders of magnitude stronger than any received signals. The transmitted signal may be powerful enough to make simultaneous reception of received signals impossible, particularly where the received signal is received on the same or a nearby frequency as the signal being transmitted. However, simultaneous transmission and reception of signals in a frequency hopping system remains desirable.
Accordingly, there is a need for a system and method allowing for simultaneous transmission and reception of signals in a frequency hopping system. Yet further, there is a need for such a system and method configured to assign a frequency to one of a plurality of transceivers based on a frequency of a second transmitter upon which a signal is being received. There is further a need for such system and method wherein the one of a plurality of transceivers is selected based on a desired isolation level.
It would be desirable to provide a system and/or method that provides one or more of these or other advantageous features. Other features and advantages will be made apparent from the present specification. The teachings disclosed extend to those embodiments which fall within the scope of the appended claims, regardless of whether they accomplish one or more of the aforementioned needs.
One embodiment of the invention relates to a system for simultaneously transmitting and receiving signals in a frequency hopping system. The system includes a multiplexor configured to filter a plurality of frequency hopping message pulses based on a frequency associated with each pulse, a plurality of transceivers configured to receive the pulses from the multiplexor, and a modem configured for simultaneous transmission and reception whereby transmission of the pulses are isolated from potentially received pulses by selecting a specific sub-band and transceiver corresponding to the specific sub-band through which to transmit each pulse.
Another embodiment of the invention relates to a system for simultaneously transmitting and receiving signals in a frequency hopping system. The system includes a multiplexor means configured to filter a plurality of frequency hopping message pulses based on a frequency associated with each pulse, a plurality of transceiving means configured to receive the pulses from the multiplexor, and a modem means configured for simultaneous transmission and reception whereby transmission of the pulses are isolated from potentially received pulses by selecting a specific sub-band and transceiver corresponding to the specific sub-band through which to transmit each pulse.
Yet another embodiment of the invention relates to a computer implemented method for simultaneously transmitting and receiving signals in a frequency hopping system. The method includes transmitting a frequency hopping message pulse on a frequency associated with the transmitted pulse, receiving a frequency hopping message pulse on a different frequency associated with the received pulse during the transmission of the transmitted pulse, and assigning a frequency to the transmitted pulse based on a frequency associated with the received pulses by selecting a specific sub-band and transceiver corresponding to the specific sub-band.
Alternative examples of other exemplary embodiments are also provided which relate to other features and combinations of features as may be generally recited in the claims.
The invention will become more fully understood from the following detailed description, taken in conjunction with the accompanying drawings, wherein like reference numerals refer to like elements, in which:
Before describing in detail the particular improved system and method, it may be observed that the invention includes, but is not limited to, a novel structural combination of conventional data/signal processing components and communication circuits, and not in the particular detailed configurations thereof. Accordingly, the structure, methods, functions, control, and arrangement of conventional components and circuits have, for the most part, been illustrated in the drawings by readily understandable block representations and schematic diagrams in order not to obscure the disclosure with structural details which will be readily apparent to those skilled in the art, having the benefit of the description herein. Further, the invention is not limited to the particular embodiment depicted in the exemplary diagrams, but may be construed in accordance with the language in the claims.
Referring now to
Architecture 100 includes an antenna 110, a multiplexor 120, a plurality of transceivers 130, and a modulator/demodulator, or modem 140. Although a particular number of elements are shown in
Antenna 110 may be any type of antenna configured to receive transmitted digital signals over a variety of frequencies. Multiplexor 120 may be any type of multiplexor configured to divide the signal received from antenna 110 in N sub-bands, where N is equal to the number of transceivers 130, and to provide isolation between each of the sub-bands. Each sub-band corresponds to one of the N transceivers 130. The multiplexor 120 acts as a filter separating the received or transmitted signals based on the frequency sub-bands.
Transceivers 130 may be any type of transceiver configured to be capable of receive or transmit functionality. Transceivers 130 may further be configured to transmit in a half-duplex fashion. Transceivers 130 are configured to be isolated from each other to minimize interference. By providing isolation between sub-bands of the total frequency hopping bandwidth, architecture 100 enables reception of a signal during a transmitted pulse. Reception is possible when the received signal is in a different sub-band from the transmitted pulse.
Transceivers 130 may be configured such that each transceiver is associated with a unique frequency or a unique group of several contiguous frequencies (a frequency sub-band). The associations may be stored and maintained by modem 140. The associated frequencies may further be fixed or variable. For example, modem 140 may be configured to narrow the frequency sub-bands associated with transceivers 130 based on a transmission power to provide greater isolation between transceivers 130. To illustrate, assuming a first sub-band of frequencies and a second sub-band of frequencies, modem 140 may configure the sub-bands to be separated by a certain number of frequencies, the number may be a function of the transmit power of architecture 100.
Modem 140 may be any standard modulator/demodulator configured to accept and process received signals from the plurality of transceivers 130. Modem 140 is further configured to send a modulated signal to one or more of the transceivers 130 while simultaneously processing received signals from one or more of transceivers 130.
Modem 140 is configured to include a digital signal processor 142 configured to implement the signal processing required to simultaneously receive signals while transmitting as described in detail below with reference to
Embodiments of the present invention may be practiced in a networked environment using logical connections to one or more remote computing systems having processors. Logical connections may include a local area network (LAN) and a wide area network (WAN) that are presented here by way of example, and not limitation. Such networking environments are commonplace in office-wide or enterprise-wide computer networks, intranets and the Internet and may use a wide variety of different communication protocols. Those skilled in the art will appreciate that such network computing environments will typically encompass many types of computer system configurations, including personal computers, hand-held devices, multi-processor systems, microprocessor-based or programmable consumer electronics, network PC's, minicomputers, mainframe computers, and the like. Embodiments of the invention may also be practiced in distributed computing environments where tasks are performed by local and remote processing devices that are linked (either by hardwired links, wireless links, or by a combination of hardwired and wireless links) through a communications network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.
Referring now to
The graph depicted in
Referring now to
In a step 310, modem 140 may be configured to modulate a message to be provided to a transceiver for transmission. Transmission may further include dividing the message to be sent into a plurality of pulses or dwells, wherein each pulse is configured to be transmitted on a pseudorandom frequency. Transmission may further include transmitting each pulse to one of transceivers 130 based on the pseudorandom frequency that is selected for the pulse and a frequency or band of frequencies uniquely associated with each of transceivers 130.
Transmission may further include commanding the transceiver 130 to transmit on a particular frequency within the sub-band for that transmitter. Commanding the transceiver 130 to transmit on a particular frequency may be used to facilitate isolation between transceivers. Each pulse or dwell is being sent on a pseudorandom frequency; accordingly, the isolated frequency will also be changed in real time.
In a step 320, occurring concurrently with step 310, modem 140 is configured to listen for, and receive messages through other transceivers 130 from those being utilized in step 310. The received messages may also be frequency hopping messages received on a plurality of pseudorandom frequencies.
In a step 330, modem 140 may be configured to perform forward error correction to allow for recovery of packets for which collisions have occurred by transceivers transmitting on the same frequency on which a pulse is currently or about to be received. Transmitted frequencies are generally chosen pseudo randomly such that collisions may occur.
It is important to note that although the steps in
It may be noted that although the flowcharts provided herein shows a specific order of method steps, it is understood that the order of these steps may differ from what is depicted. Also, two or more steps may be performed concurrently or with partial concurrence. Such variation will depend on the software and hardware systems chosen and on designer choice. It is understood that all such variations are within the scope of the invention. Likewise, software and web implementations of the present invention could be accomplished with standard programming techniques with rule-based logic and logic to accomplish the various database searching steps, correlation steps, comparison steps, and decision steps. It may also be noted that the word “processor” as used herein and in the claims is intended to encompass implementations using one or more lines of software code, and/or hardware implementations, and/or equipment for receiving manual inputs.
Embodiments within the scope of the present invention include program products comprising machine-readable media for carrying or having machine-executable instructions or data structures stored thereon. Such machine-readable media can be any available media which can be accessed by a general purpose or special purpose computer or other machine with a processor. By way of example, such machine-readable media can comprise RAM, ROM, EPROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code in the form of machine-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer or other machine with a processor. When information is transferred or provided over a network or another communication connection (either hardwired, wireless, or a combination of hardwired or wireless) to a machine, the machine properly views the connection as a machine-readable medium. Thus, any such connection is properly termed “machine-readable medium.” Combinations of the above are also included within the scope of machine-readable media. Machine-executable instructions comprise, for example, instructions and data which cause a general purpose computer, special purpose computer, or special purpose processing machine to perform a certain function or group of functions.
Embodiments of the invention are described in the general context of method steps which may be implemented in one embodiment by a program product including machine-executable instructions, such as program code, for example, in the form of program modules executed by machines in networked environments. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Machine-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods described herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps.
While the detailed drawings, specific examples, and particular formulations given describe preferred and exemplary embodiments, they serve the purpose of illustration only. The inventions disclosed are not limited to the specific forms shown. For example, the methods may be performed in any of a variety of sequence of steps. The hardware and software configurations shown and described may differ depending on the chosen performance characteristics and physical characteristics of the computing devices. For example, the type of computing device, communication bus or processor used may differ. The systems and methods depicted and described are not limited to the precise details and conditions disclosed. Furthermore, other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the exemplary embodiment without departing from the scope of the invention as expressed in the appended claims.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US4383323||Jun 9, 1980||May 10, 1983||Bell Telephone Laboratories, Incorporated||Spread spectrum FH-MFSK transmitter and receiver|
|US4688251||Jan 21, 1986||Aug 18, 1987||The Singer Company||Wave packet communication subsystem for determining the sync pulses and correlating the data pulses of a wave packet|
|US4970479 *||Nov 27, 1989||Nov 13, 1990||Rockwell International Corporation||Multicoupler including frequency shift filters|
|US5329548 *||Mar 26, 1993||Jul 12, 1994||Telefonaktiebolaget L. M. Ericsson||Base station for a frequency hopping TDMA radio communication system|
|US5408260 *||Jan 11, 1994||Apr 18, 1995||Northern Telecom Limited||Customer premises ADSL signal distribution arrangement|
|US5422952||Jun 3, 1992||Jun 6, 1995||Itt Corporation||Dynamic radio communications system|
|US5625641||Dec 27, 1995||Apr 29, 1997||Matsushita Electric Industrial Co., Ltd.||Correlator, synchronizer provided with the correlator, and fast frequency hopping spread spectrum receiver provided with the synchronizer|
|US5715236||Nov 24, 1993||Feb 3, 1998||Qualcomm Incorporated||System and method for generating signal waveforms in a CDMA cellular telephone system|
|US5757767||Oct 29, 1996||May 26, 1998||Qualcomm Incorporated||Method and apparatus for joint transmission of multiple data signals in spread spectrum communication systems|
|US5781582||May 4, 1995||Jul 14, 1998||Interwave Communications International Ltd.||Frequency agile transceiver with multiple frequency synthesizers per transceiver|
|US5832026||Dec 4, 1996||Nov 3, 1998||Motorola, Inc.||Method for correcting errors from a fading signal in a frequency hopped spread spectrum communcation system|
|US5914933||Oct 15, 1996||Jun 22, 1999||Lucent Technologies Inc.||Clustered OFDM communication system|
|US5930244||Jul 7, 1997||Jul 27, 1999||Hitachi, Ltd.||CDMA Communication system and method|
|US5943361||May 16, 1995||Aug 24, 1999||Qualcomm Incorporated||System and method for generating signal waveforms in a CDMA cellular telephone system|
|US6049535||Mar 11, 1997||Apr 11, 2000||Interdigital Technology Corporation||Code division multiple access (CDMA) communication system|
|US6088337||Oct 20, 1997||Jul 11, 2000||Motorola, Inc.||Method access point device and peripheral for providing space diversity in a time division duplex wireless system|
|US6169761||Apr 1, 1998||Jan 2, 2001||Wavespan Corporation||Method and transceiver using an improved protocol for a frequency hop communication system|
|US6246698||Nov 24, 1998||Jun 12, 2001||Digital Radio Express, Inc.||In-band on-channel digital broadcasting method and system|
|US6320896||Jul 14, 1998||Nov 20, 2001||Intermec Ip Corp.||RF receiver having frequency-hopping/direct-sequence spread spectrum signal discrimination|
|US6498820||May 6, 1999||Dec 24, 2002||3Com Corporation||Low complexity frequency estimator and interference cancellation method and device|
|US6519262||Jun 10, 1998||Feb 11, 2003||Trw Inc.||Time division multiplex approach for multiple transmitter broadcasting|
|US6522650||Aug 4, 2000||Feb 18, 2003||Intellon Corporation||Multicast and broadcast transmission with partial ARQ|
|US6658063||Jul 17, 2000||Dec 2, 2003||Nippon Telegraph And Telephone Corporation||OFDM packet communication receiver system|
|US6671331||Nov 16, 1999||Dec 30, 2003||Nec Corporation||Carrier detecting circuit for detecting the level of a received signal and communication apparatus|
|US6686829||Jan 19, 1999||Feb 3, 2004||Zih Corp.||Electronic identification system with forward error correction system|
|US6693580 *||Sep 4, 2002||Feb 17, 2004||Northrop Grumman Corporation||Multifunction millimeter-wave system for radar, communications, IFF and surveillance|
|US6721331||Dec 15, 1999||Apr 13, 2004||At&T Corp.||Method and apparatus for decentralized prioritized scheduling in a CSMA/CA wireless system|
|US6788729 *||Oct 22, 1999||Sep 7, 2004||Nokia Networks Oy||Frequency hopping method and base station|
|US6810258 *||Jun 29, 2000||Oct 26, 2004||Nokia Corporation||Contention resolution method in channel allocation|
|US6836469||Jan 15, 1999||Dec 28, 2004||Industrial Technology Research Institute||Medium access control protocol for a multi-channel communication system|
|US6904282||Nov 16, 2001||Jun 7, 2005||Qualcomm Incorporated||Method and apparatus for identifying and acquiring preferred wireless communications systems|
|US6917606||Mar 22, 2001||Jul 12, 2005||Nec Corporation||Priority data transfer method|
|US7033322 *||Nov 8, 2001||Apr 25, 2006||Silver James H||Implantable sensor|
|US7088734||Mar 27, 2001||Aug 8, 2006||Motorola, Inc.||Slot format and method for increasing random access opportunities in a wireless communication system|
|US7142521||Mar 13, 2002||Nov 28, 2006||Transcore Link Logistics Corporation||Wireless packet data distributed communications system|
|US7292617||Nov 3, 2003||Nov 6, 2007||Strix Systems, Inc.||Reducing mutual channel interference in frequency-hopping spread spectrum wireless communication systems|
|US20020009067||Jun 28, 2001||Jan 24, 2002||Joachim Sachs||Method and device for improving the transmission efficiency in a communication system with a layered protocol stack|
|US20030012217||Oct 29, 1999||Jan 16, 2003||Christoffer Andersson||Channel-type switching to a common channel based on common channel load|
|US20030053469||Aug 31, 2001||Mar 20, 2003||Wentink Maarten Menzo||System and method for ordering data messages having differing levels of priority for transmission over a shared communication channel|
|US20040087308 *||Jan 29, 2002||May 6, 2004||Olav Tirkkonen||Data transfer method in radio system|
|US20040203460||Nov 8, 2002||Oct 14, 2004||Jun Hasegawa||Radio communication apparatus and method of controlling the same|
|US20050013386||Jun 22, 2004||Jan 20, 2005||Ojard Eric J.||Multi-band single-carrier modulation|
|US20050030914||Aug 8, 2003||Feb 10, 2005||Charles Binzel||Incoming message decoding in wireless communications devices and methods|
|US20050242990||Apr 29, 2004||Nov 3, 2005||Integrinautics Corporation||Signal path system and method for a ranging signal receiver|
|US20050254560||May 17, 2004||Nov 17, 2005||Huang Yi P||Apparatus and method for acquiring spread-spectrum signals|
|US20060018391||Jul 20, 2004||Jan 26, 2006||Chun-Ming Cho||Method and apparatus of detecting isi/icsi in an ofdm system|
|US20060045053 *||Sep 11, 2003||Mar 2, 2006||Yossi Erlich||Method for data transmission within a wireless local area network|
|US20070238483 *||Apr 5, 2006||Oct 11, 2007||Olivier Boireau||Antenna sharing techniques|
|US20070282908 *||Jun 5, 2006||Dec 6, 2007||Palm, Inc.||Techniques for managing media content|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US8897318 *||Nov 29, 2011||Nov 25, 2014||Realtek Semiconductor Corp.||Network device and network connecting method|
|US20120134372 *||Nov 29, 2011||May 31, 2012||Liang-Wei Huang||Network device and network connecting method|
|U.S. Classification||375/219, 375/222, 375/132|
|Cooperative Classification||H04B1/7143, H04B1/713|
|European Classification||H04B1/713, H04B1/7143|
|Jul 19, 2007||AS||Assignment|
Owner name: ROCKWELL COLLINS, INC., IOWA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:CHAVEZ, CARLOS J.;FRANK, ROBERT JOSEPH;VAGHER, MICHAEL R.;AND OTHERS;SIGNING DATES FROM 20070322 TO 20070329;REEL/FRAME:019577/0349
|May 16, 2014||FPAY||Fee payment|
Year of fee payment: 4