CA2045519C - Dsp based radio with diminished power requirements - Google Patents
Dsp based radio with diminished power requirementsInfo
- Publication number
- CA2045519C CA2045519C CA002045519A CA2045519A CA2045519C CA 2045519 C CA2045519 C CA 2045519C CA 002045519 A CA002045519 A CA 002045519A CA 2045519 A CA2045519 A CA 2045519A CA 2045519 C CA2045519 C CA 2045519C
- Authority
- CA
- Canada
- Prior art keywords
- signal
- signal processing
- processing means
- power
- digital 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.)
- Expired - Fee Related
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details 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
- H04B1/06—Receivers
- H04B1/16—Circuits
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/02—Power saving arrangements
- H04W52/0209—Power saving arrangements in terminal devices
- H04W52/0261—Power saving arrangements in terminal devices managing power supply demand, e.g. depending on battery level
- H04W52/0274—Power saving arrangements in terminal devices managing power supply demand, e.g. depending on battery level by switching on or off the equipment or parts thereof
- H04W52/028—Power saving arrangements in terminal devices managing power supply demand, e.g. depending on battery level by switching on or off the equipment or parts thereof switching on or off only a part of the equipment circuit blocks
- H04W52/0283—Power saving arrangements in terminal devices managing power supply demand, e.g. depending on battery level by switching on or off the equipment or parts thereof switching on or off only a part of the equipment circuit blocks with sequential power up or power down of successive circuit blocks, e.g. switching on the local oscillator before RF or mixer stages
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/02—Power saving arrangements
- H04W52/0209—Power saving arrangements in terminal devices
- H04W52/0261—Power saving arrangements in terminal devices managing power supply demand, e.g. depending on battery level
- H04W52/0287—Power saving arrangements in terminal devices managing power supply demand, e.g. depending on battery level changing the clock frequency of a controller in the equipment
- H04W52/0293—Power saving arrangements in terminal devices managing power supply demand, e.g. depending on battery level changing the clock frequency of a controller in the equipment having a sub-controller with a low clock frequency switching on and off a main controller with a high clock frequency
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Circuits Of Receivers In General (AREA)
- Mobile Radio Communication Systems (AREA)
- Power Sources (AREA)
Abstract
A radio (100) having two signal processing paths, one including a digital signal processor (104) that consumes a relatively large amount of power and one including a signal processor (106) that consumes a relatively small amount of power. The low power processor (106) operates to monitor for broadcast signals of interest.
Upon detecting such a signal, the low power processor (106) enables the digital signal processor (104) to facilitate proper signal processing.
Upon detecting such a signal, the low power processor (106) enables the digital signal processor (104) to facilitate proper signal processing.
Description
WO 90/116~2 2 0 ~ ~ 5 ~ 9 PCr~USgO/01336 DSP BASED RADIO WITH DIMINISHED
POWER REQUIREMENTS
Te.~h~cal Fie~
This invention relates generally to radios, and more particularly to radios that include a digital signal processor.
Back~rQunsi Art Radios generally function to receive broadcast signals.
Usually~ the user of a radio will not be interested in all of the signals 20 that are broadcas~ on a communication resource (such as a particular frequency or a particular TDM time slot). Since many broadcast signals of interest include an identifying signal or other identifying indicia, many radios include a signal processor that examines the received broadcast signal to determine the presence of 2~ the identifying signal. If present, the radio can be further enabled to render the broadcast signal audible! visible, or otherwise as appropriate for that particular broadcast signal.
For example, some radios remain squelched unless a carrier can be sensed on a particular monitorsd communication resource.
30 Other broadcast signals include special identifying signals, such as tone signals or subaudible digital signals, that the radio can recognize and respond to. Yet other signals of interest can be ~ l ;
WO 90/11652 PCI'/U~;90/01336 ~045~1~
prefaced with a specific identifying pr~3amble, such as an ID for the intended radio.
In order to expand the capabiiities and flexibility of radios, digitizers and digital signal processors (DSPs) have been used.
These processors typically receive digitized received signals. Further processing of the signal, equivalent to IF and discriminator processing, then occurs in the DSP in a digital manner. The resultant signal can then be converted into analog form and processed further as appropriate. For example, the resultant signal may be rendered 10 audible in the case of a voice transmission.
DSPs, however, consume a significant amount of power when operating. This becomes a particular problem when seeking to use a DSP in a portable radio with limited power resources. DSP power consumption becomes of particular concern when the DSP operates 15 both in the presence and absence of a broadcast signal of interest.
Typically, the DSP must operate even in the absence of a broadcast signal of interest because the DSP itself aids in detecting the presence of a broadcast signal of interest. Unless the broadcast signals of.interest occur at known times, the DSP must remain active 20 in order to detect the signal when it occurs.
Surrlrn~ of the Invention:
This invention allows a DSP to be used in a radio while 25 avoiding the necessity of continuous DSP operation.
The invention includes general!y two signal processing units, the first includes the DSP and the second includes a processing unit having lesser capabilities and smaller power requirements. The DSP
based signal processing unit functions ~o fully process broadcast 30 signals of interest. The low power processing unit functions to detect the presence of a broadcast signal of interest, and upon detecting WO 90/1165~ 2 0 ~ ~ ~ 1 9 Pcr/vs9o/ol336 such a signal, the low power processing unit enables the DSP
based processing unit to begin functioning.
Through use of this invention, the high power requirements of the DSP based processing unit are necessitated only when a 5 broadcast signal of interest exists. Otherwise, a lower power broadcast signal of interest detection mechanism monitors the communication resource.
Brief Descri~Qn of the Drawin~;
Fig. 1 comprises a block diagram depiction of the invention;
Fig. 2 comprises a block diagram depiction of the low power signal processing unit.
15 Best MQsle for Carrying out the InventiQn:
Referring to Fig. 1, a radio (100) includes generally an antenna (101) for receiving broadcast signals and an RF unit (102) for appropriately processing the received broadcast signals. The 20 received signals are then passed to a low power signal processing unit (106) and also through an appropriate gate (103) to a digital signal processing unit (104) (the lattertypically including a DSP such as the Motorola 560Q0 and a microprocessor to control the DSP).
The output of the digital signal processing unit (104) then couples to 2~ an appropriate amplifier (107) and speaker (108) or other output devices as appropriate to the type of message received.
With reference to Fig. 2, the low power signal processing unit (106) includes an appropriate IF unit (201 ) for receiving the output signal from the RF unit (102), a discriminator (202) for processing the 30 IF unit (201) output to aid in recovering the original modulating signal, and a processing unit (203) for examining the recovered signal and determining whether an appropriate identifying signal is WO 90/11652 ~ ` PCI'/~JS~0/01336 9 ~ .
present. The processing unit (203) could be any relatively simple and low power device, such as a Motoro!a MC6303 processor.
Upon detecting the presence of a broadcast signal of interest, the processing unit (203) of the low power signal processing unit 5 provides a signal to the gate (103), thereby allowing the RF signal to be provided to the digital signal processing unit (104). At the same time, the processing unit (203) provides an enable signal to the digital signal processing unit ~104) ~o activate that unit and cause it to begin processing the incoming signal.
So configured, the digital signal processing unit will operate only when a broadcast signal of interest can be detected. Otherwise, the low power signal processing unit will moni~or the received broadcast signals and control the activation of the digital signal processing unit as a function of the presence and absence of a 1 5 broadcast signal of interest.
/
POWER REQUIREMENTS
Te.~h~cal Fie~
This invention relates generally to radios, and more particularly to radios that include a digital signal processor.
Back~rQunsi Art Radios generally function to receive broadcast signals.
Usually~ the user of a radio will not be interested in all of the signals 20 that are broadcas~ on a communication resource (such as a particular frequency or a particular TDM time slot). Since many broadcast signals of interest include an identifying signal or other identifying indicia, many radios include a signal processor that examines the received broadcast signal to determine the presence of 2~ the identifying signal. If present, the radio can be further enabled to render the broadcast signal audible! visible, or otherwise as appropriate for that particular broadcast signal.
For example, some radios remain squelched unless a carrier can be sensed on a particular monitorsd communication resource.
30 Other broadcast signals include special identifying signals, such as tone signals or subaudible digital signals, that the radio can recognize and respond to. Yet other signals of interest can be ~ l ;
WO 90/11652 PCI'/U~;90/01336 ~045~1~
prefaced with a specific identifying pr~3amble, such as an ID for the intended radio.
In order to expand the capabiiities and flexibility of radios, digitizers and digital signal processors (DSPs) have been used.
These processors typically receive digitized received signals. Further processing of the signal, equivalent to IF and discriminator processing, then occurs in the DSP in a digital manner. The resultant signal can then be converted into analog form and processed further as appropriate. For example, the resultant signal may be rendered 10 audible in the case of a voice transmission.
DSPs, however, consume a significant amount of power when operating. This becomes a particular problem when seeking to use a DSP in a portable radio with limited power resources. DSP power consumption becomes of particular concern when the DSP operates 15 both in the presence and absence of a broadcast signal of interest.
Typically, the DSP must operate even in the absence of a broadcast signal of interest because the DSP itself aids in detecting the presence of a broadcast signal of interest. Unless the broadcast signals of.interest occur at known times, the DSP must remain active 20 in order to detect the signal when it occurs.
Surrlrn~ of the Invention:
This invention allows a DSP to be used in a radio while 25 avoiding the necessity of continuous DSP operation.
The invention includes general!y two signal processing units, the first includes the DSP and the second includes a processing unit having lesser capabilities and smaller power requirements. The DSP
based signal processing unit functions ~o fully process broadcast 30 signals of interest. The low power processing unit functions to detect the presence of a broadcast signal of interest, and upon detecting WO 90/1165~ 2 0 ~ ~ ~ 1 9 Pcr/vs9o/ol336 such a signal, the low power processing unit enables the DSP
based processing unit to begin functioning.
Through use of this invention, the high power requirements of the DSP based processing unit are necessitated only when a 5 broadcast signal of interest exists. Otherwise, a lower power broadcast signal of interest detection mechanism monitors the communication resource.
Brief Descri~Qn of the Drawin~;
Fig. 1 comprises a block diagram depiction of the invention;
Fig. 2 comprises a block diagram depiction of the low power signal processing unit.
15 Best MQsle for Carrying out the InventiQn:
Referring to Fig. 1, a radio (100) includes generally an antenna (101) for receiving broadcast signals and an RF unit (102) for appropriately processing the received broadcast signals. The 20 received signals are then passed to a low power signal processing unit (106) and also through an appropriate gate (103) to a digital signal processing unit (104) (the lattertypically including a DSP such as the Motorola 560Q0 and a microprocessor to control the DSP).
The output of the digital signal processing unit (104) then couples to 2~ an appropriate amplifier (107) and speaker (108) or other output devices as appropriate to the type of message received.
With reference to Fig. 2, the low power signal processing unit (106) includes an appropriate IF unit (201 ) for receiving the output signal from the RF unit (102), a discriminator (202) for processing the 30 IF unit (201) output to aid in recovering the original modulating signal, and a processing unit (203) for examining the recovered signal and determining whether an appropriate identifying signal is WO 90/11652 ~ ` PCI'/~JS~0/01336 9 ~ .
present. The processing unit (203) could be any relatively simple and low power device, such as a Motoro!a MC6303 processor.
Upon detecting the presence of a broadcast signal of interest, the processing unit (203) of the low power signal processing unit 5 provides a signal to the gate (103), thereby allowing the RF signal to be provided to the digital signal processing unit (104). At the same time, the processing unit (203) provides an enable signal to the digital signal processing unit ~104) ~o activate that unit and cause it to begin processing the incoming signal.
So configured, the digital signal processing unit will operate only when a broadcast signal of interest can be detected. Otherwise, the low power signal processing unit will moni~or the received broadcast signals and control the activation of the digital signal processing unit as a function of the presence and absence of a 1 5 broadcast signal of interest.
/
Claims (2)
1. In a radio having a signal receiving means for receiving radio frequency broadcast signals, and a digital signal processing means, receiving radio frequency signals from said receiving means, that requires a first amount of power to operate for converting the received broadcast signals in to a first signal, an improvement comprising:
A) switch means:
responsive to an enabling control signal; and being operably coupled between the signal receiving means and the digital signal processing means;
for selectively allowing the broadcast signal as received by the signal receiving means to be provided to the digital signal processing means;
B) low power signal processing means:
operably coupled to the signal receiving means and receiving radio frequency signals from said signal receiving means; and requiring a second amount of power, said second amount of power being less that the first amount of power;
for detecting a radio frequency broadcast signal of interest independent of the digital signal processing means and providing the enabling control signal to the switch means and the digital signal processing means in response thereto for activating the digital signal processing means and allowing the received broadcast signals to be provided to the digital signal processing means.
A) switch means:
responsive to an enabling control signal; and being operably coupled between the signal receiving means and the digital signal processing means;
for selectively allowing the broadcast signal as received by the signal receiving means to be provided to the digital signal processing means;
B) low power signal processing means:
operably coupled to the signal receiving means and receiving radio frequency signals from said signal receiving means; and requiring a second amount of power, said second amount of power being less that the first amount of power;
for detecting a radio frequency broadcast signal of interest independent of the digital signal processing means and providing the enabling control signal to the switch means and the digital signal processing means in response thereto for activating the digital signal processing means and allowing the received broadcast signals to be provided to the digital signal processing means.
2. In a radio having a radio frequency signal receiving means for receiving radio frequency broadcast signals, and digital signal processing means, receiving said radio frequency signals from said radio frequency signal receiving means, that require a first amount of power to operate for converting the received broadcast signals into a first signal, an improvement comprising low power signal processing means:
operably coupled to the radio frequency signal receiving means and receiving radio frequency signals; and requiring a second amount of power, said second amount of power being less than the first amount of power;
for detecting a radio frequency broadcast signal of interest independent of the digital signal processing means and providing an enabling control signal to the digital signal processing means for activating the digital signal processing means to substantially control power consumption of the digital signal processing means.
operably coupled to the radio frequency signal receiving means and receiving radio frequency signals; and requiring a second amount of power, said second amount of power being less than the first amount of power;
for detecting a radio frequency broadcast signal of interest independent of the digital signal processing means and providing an enabling control signal to the digital signal processing means for activating the digital signal processing means to substantially control power consumption of the digital signal processing means.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US32560389A | 1989-03-20 | 1989-03-20 | |
| US325,603 | 1989-03-20 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2045519A1 CA2045519A1 (en) | 1990-09-21 |
| CA2045519C true CA2045519C (en) | 1994-11-08 |
Family
ID=23268578
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002045519A Expired - Fee Related CA2045519C (en) | 1989-03-20 | 1990-03-13 | Dsp based radio with diminished power requirements |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0463104A4 (en) |
| JP (1) | JPH04504340A (en) |
| KR (1) | KR950000050B1 (en) |
| CA (1) | CA2045519C (en) |
| WO (1) | WO1990011652A1 (en) |
Families Citing this family (26)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE464437B (en) * | 1989-08-25 | 1991-04-22 | Ericsson Telefon Ab L M | METHOD OF A MOGIL RADIO RECEIVER TO REDUCE THE POWER RECEIVER'S REQUIREMENT |
| US5790946A (en) | 1993-07-15 | 1998-08-04 | Rotzoll; Robert R. | Wake up device for a communications system |
| FI97765C (en) * | 1993-11-26 | 1997-02-10 | Nokia Mobile Phones Ltd | A method and a switching arrangement for processing paging messages in a mobile station |
| CA2135856A1 (en) * | 1993-12-10 | 1995-06-11 | Steven Peter Allen | Low power, addressable data communication device and method |
| US7092369B2 (en) | 1995-11-17 | 2006-08-15 | Symbol Technologies, Inc. | Communications network with wireless gateways for mobile terminal access |
| JP2852245B2 (en) * | 1996-06-18 | 1999-01-27 | 静岡日本電気株式会社 | Radio selective call receiver |
| DE69823162T2 (en) * | 1998-02-26 | 2004-08-26 | Motorola Semiconducteurs S.A. | Energy saving arrangement for an electronic portable device |
| CN1188953C (en) * | 1998-09-28 | 2005-02-09 | 索尼电脑娱乐公司 | Method and apparatus for transceiving, receiving as well as transmitting |
| US6278403B1 (en) | 1999-09-17 | 2001-08-21 | Sirf Technology, Inc. | Autonomous hardwired tracking loop coprocessor for GPS and WAAS receiver |
| US6389291B1 (en) | 2000-08-14 | 2002-05-14 | Sirf Technology | Multi-mode global positioning system for use with wireless networks |
| US6462708B1 (en) | 2001-04-05 | 2002-10-08 | Sirf Technology, Inc. | GPS-based positioning system for mobile GPS terminals |
| US6427120B1 (en) | 2000-08-14 | 2002-07-30 | Sirf Technology, Inc. | Information transfer in a multi-mode global positioning system used with wireless networks |
| US6671620B1 (en) | 2000-05-18 | 2003-12-30 | Sirf Technology, Inc. | Method and apparatus for determining global position using almanac information |
| ATE507486T1 (en) | 2000-08-24 | 2011-05-15 | Sirf Tech Inc | DEVICE FOR REDUCING AUTOCORRELATION AND CROSS-CORRELATION IN WEAK CDMA SIGNALS |
| US7047023B1 (en) | 2000-12-01 | 2006-05-16 | Sirf Technology, Inc. | GPS RF front end IC with frequency plan for improved integrability |
| US7747236B1 (en) | 2000-12-11 | 2010-06-29 | Sirf Technology, Inc. | Method and apparatus for estimating local oscillator frequency for GPS receivers |
| US7113552B1 (en) | 2000-12-21 | 2006-09-26 | Sirf Technology, Inc. | Phase sampling techniques using amplitude bits for digital receivers |
| US6680703B1 (en) | 2001-02-16 | 2004-01-20 | Sirf Technology, Inc. | Method and apparatus for optimally tuning a circularly polarized patch antenna after installation |
| US6703971B2 (en) | 2001-02-21 | 2004-03-09 | Sirf Technologies, Inc. | Mode determination for mobile GPS terminals |
| US7076256B1 (en) | 2001-04-16 | 2006-07-11 | Sirf Technology, Inc. | Method and apparatus for transmitting position data using control channels in wireless networks |
| US7877104B2 (en) | 2001-05-21 | 2011-01-25 | Sirf Technology Inc. | Method for synchronizing a radio network using end user radio terminals |
| US7925210B2 (en) | 2001-05-21 | 2011-04-12 | Sirf Technology, Inc. | Synchronizing a radio network with end user radio terminals |
| JP4658050B2 (en) | 2003-09-02 | 2011-03-23 | サーフ テクノロジー インコーポレイテッド | Signal processing system for satellite positioning signals |
| US8532718B2 (en) * | 2005-10-06 | 2013-09-10 | Broadcom Corporation | Mobile communication device with low power signal detector |
| CN100525231C (en) * | 2006-09-06 | 2009-08-05 | ***通信集团公司 | Energy-saving information household appliance network and energy-saving control method |
| US8442475B2 (en) * | 2010-11-15 | 2013-05-14 | Qualcomm Incorporated | Power conservation in wireless access terminals using integrated proxy function |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3753122A (en) * | 1971-03-31 | 1973-08-14 | K Shackleford | Frequency responsive radio actuator for automatically connecting the receiver portion and the audio portion |
| US4419765A (en) * | 1979-10-12 | 1983-12-06 | Keith H. Wycoff | Signal absence detector |
| JPS61240719A (en) * | 1985-04-18 | 1986-10-27 | Nec Corp | Receiver |
| GB2201866B (en) * | 1987-03-04 | 1991-04-17 | Michael Victor Rodrigues | Improvements in or relating to cellular telephone apparatus and a cellular communications system |
-
1990
- 1990-03-13 CA CA002045519A patent/CA2045519C/en not_active Expired - Fee Related
- 1990-03-13 EP EP19900905882 patent/EP0463104A4/en not_active Withdrawn
- 1990-03-13 KR KR1019900702452A patent/KR950000050B1/en not_active IP Right Cessation
- 1990-03-13 JP JP2505473A patent/JPH04504340A/en active Pending
- 1990-03-13 WO PCT/US1990/001336 patent/WO1990011652A1/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| WO1990011652A1 (en) | 1990-10-04 |
| EP0463104A1 (en) | 1992-01-02 |
| CA2045519A1 (en) | 1990-09-21 |
| JPH04504340A (en) | 1992-07-30 |
| EP0463104A4 (en) | 1993-01-13 |
| KR920700497A (en) | 1992-02-19 |
| KR950000050B1 (en) | 1995-01-07 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |