stands for Global Positioning System, a satellite based navigation system

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-4
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0answers
45 views

What is the no power long range GPS chip used in the Shot Genius golf ball? [on hold]

The Shot Genius golf ball advertises that it contains a 'no power high precision long range GPS chip'. The system claims to allow a player to hit the golf ball down the course and then look at a ...
0
votes
1answer
31 views

Generating Hexadecimal checksum for a NMEA (PMTK) message

I am trying to use quectel L80 GPS receiver for my project. I am trying to configure the L80 using the PMTK strings. But the problem is the string should also contain a hexadecimal check sum. eg. ...
7
votes
1answer
149 views

how is the 1PPS signal generated in GPS receivers?

The question might seem stupid, but the time of flight from the satellite is unknown and moving, the doppler effect is skewing the frequency (and is not constant due to the relative trajectory) and ...
0
votes
2answers
59 views

GPS 1 PPS Aligment Clock Signal Generator

i want to do GPS 1 pps aligment clock signal generator. Clock signal should be at 24.576 Mhz and voltage level Vmax= 3.3 V and Vmin=0 V DC. How can i do that? It is very important to align between GPS ...
0
votes
1answer
73 views

GPS Almanac versus Sky Search

The total almanac data is transmitted in 25 navigation messages. Each navigation message takes at least 30 seconds to transmit. So, receiving the almanac data from the satellites takes at least 12.5 ...
0
votes
1answer
53 views

GPS antenna type

i want to interface a gps module and an antenna. I found this kind of antenna (example) It does not mention its type. Is this an active or a passive antenna? How to be able to know by myself without ...
0
votes
0answers
59 views

Designing a GPS Antenna Concept

I'm working a GPS circuit (for a handheld device that will ironically be in bags or pockets most of the time) which communicates with wifi networks. I thought a great deal about the required ...
0
votes
1answer
100 views

Problem communicating between SIM908 and Arduino UNO

I'm trying to make my Arduino UNO work with the SIM908 GPS/GSM shield with this simple code just to make sure that it works first: ...
0
votes
0answers
42 views

GPS Active Antenna Circuit

I'm adding an active antenna to a design and had a few questions. Based on multiple data sheets for similar products, everyone uses the same simple DC supply with a RF blocking inductor and DC ...
0
votes
0answers
47 views

How to communicate my location using very low power generated using my piezoelectric material?

I have been able to charge a super capacitor of 0.1f upto 3.5V by embedding it in my shoes using some piezoelectric stacks, and now I want to use the capacitor for some emergency condition. I want to ...
2
votes
1answer
62 views

Is the Garmin GPS 12 on board 16.368 MHz oscillator GPS controlled?

My plan is to use my old Garmin GPS 12 as a frequency standard. As it has no pps (pulse per second) output I am thinking about using the on board oscillator as the clock source. So my question: Is the ...
1
vote
2answers
77 views

SAW and GPS Antenna

I'm designing a system with a GSM modem and GPS receiver. In order to achieve out of band rejection I'm planning on putting a SAW filter right after the antenna. Often on the internet I see a few ...
2
votes
1answer
55 views

GPS RX module Implementation

I have been tasked with designing a low power sensor system and the customer has decided location would be a great option. I have done GPS before but only with complete modules (Ant. + IC). To keep ...
0
votes
1answer
59 views

What type of connector is this Velodyne interface box GPS connector?

Velodyne VLP-16 lidar's interface box has this connector. What type is it? Could not find this from the manual.
0
votes
2answers
192 views

Calculate distance travelled by vehicle using “knots” of NMEA data

I'm using L80 quectel GPS module. Which sends the NMEA protocol data string which has latitude, longitude, UTC time, knots, etc. We are going to use this GPS module in a vehicle. We have to calculate ...
0
votes
0answers
72 views

Schematic is not working?

I have a schematic that I turned into a PCB, but to my dismay, it is not working and I can't figure out why. Here is my schematic : I have tested the board with a multimeter (3.275v and about ...
0
votes
1answer
76 views

Antenna gps neo 6m

I am designing a pcb which has the module ublox neo 6m, instead of using the normal antenna I was looking to use a ceramic which should work with ublox. I have got this: ...
0
votes
2answers
33 views

Ways to communicate GPS coordinates to a central server wirelessly from a wearable device

I am currently looking at designing a wearable device for a client, which can communicate GPS coordinates back to some sort of central server (to then be sent out to other communicating devices such ...
3
votes
2answers
116 views

GPS positioning faster than 1Hz

I am a systems engineer working with various instrumentation devices for ground platforms. These platforms can vary in speed from 0-60+mph. Current instrumentation provides TSPI at 1Hz and is based on ...
-3
votes
1answer
59 views

External GPS antenna for smart phones [closed]

Is there a smartphone GPS boost or external GPS antenna commercially available for smartphones. To hook up to smartphones via audio input for example?
1
vote
1answer
124 views

GPS antenna ground plane design considerations and limitations

I have a PCB design which incorporates a GPS unit. I'm looking at refining the PCB, and I'm looking to do away with the long cable length, occupation of space within my enclosure, current ...
0
votes
0answers
64 views

Problem in working with GPS module

Im working with PIC24F microcontroller interfacing with GPS(Quectel L80) module and facing a weird problem. Let me explain in detail. Im using PIC's two uarts, one is for print the value and another ...
1
vote
1answer
142 views

PIC24FJ128GA202 UART2 and UART3 not working?

I am working in pic24fj128ga202 microcontroller with L80 and M95 module. here L80 module connected with uart2 and M95 module connected with uart3. now uart1 working normally but uart2 and uart3 not ...
5
votes
1answer
144 views

GPS consideration for PCB with GSM (interference, setup etc)

I am working on a project which has a GSM and GPS on the same PCB (fairly near each other in an enclosure). Since I am not familiar with GPS I was wondering if any of you could give me some tips on ...
3
votes
1answer
100 views

How is impedance matching for chip antennas practically done?

I designed a PCB for a GPS tracking device and i want to further develop it to have a smd gps antenna mounted on the board. I know that for optimal signal transfer i need to design a matching circuit, ...
0
votes
1answer
144 views

Is anything wrong with my PCB?

I am designing a PCB and I just want to make sure nothing is wrong before I send it off to the fab house. If one of you knowledgeable stack exchangers could give me some feedback, I would really ...
3
votes
0answers
88 views

GPS Power consumption MTK3339 vs SirfIII for periodic logging application

I am currently working on redesigning a SirfIII based battery operated GPS logger. A MTK3339 based GPS module has been selected due to overall (advertised) performance. The GPS logger uses a ...
0
votes
0answers
44 views

GPS antenna line feed and GND

I have designed a PCB with a GPS patch antenna soldered to it. The patch antenna is a thru-hole one and hence I have a via from the line feed. We, unfortunately have 2 issies- 1) The Antenna procured ...
1
vote
1answer
88 views

Turning a frequency locked loop into a phase locked loop

I want to use a GPS module (with a PPS output) to ultimately generate a 5kHz timing signal that is phase-aligned with the PPS positive edge. ...
1
vote
1answer
224 views

Unable to receive GPS data from Quectel L80 GPS module

I have a Quectel L80 GPS module with PIC24fj128ga202. I am using UART2 to get GPS data from the module and I transfer the received data to hyperterminal, using UART1. Between PIC and PC I there is an ...
4
votes
2answers
78 views

Is GNSS S/N equivalent to C/N?

I work in developing software that integrates with GPS and Galileo receivers. I've struggled for years with inconsistencies in documentation for the NMEA emitted by such receivers, and I've decided to ...
1
vote
1answer
90 views

How would you jerry-rig an android phone for continuous autonomous operation?

I want to use an android phone as dash-cam with GPS tracking capabilities. It is supposed to run 24 hours a day, 365 days a year. If the phone / app hangs, the user cannot be expected to ...
21
votes
4answers
3k views

True GPS Location - At the Antenna or Receiver Chip?

Suppose I have a GPS unit attached to an antenna through a 50 meter coax cable. How would the location as calculated by the GPS unit be affected by the cable length? As a bonus question, how would ...
0
votes
1answer
50 views

Reducing GPS coldstart if we know where the user is

I'm working on a project with GPS and I was wondering if it would be possible to reduce the cold start time by passing in some data. Let's say I already had a fairly good idea of where the user was ...
1
vote
1answer
89 views

Can I create paths to two external GPS antennae but use only one

I am making a PCB for a SIM968 GSM/GPS device. Printing PCBs in my country is expensive. I am making this PCB for two different purposes. One is to work in an open environment where there is enough ...
0
votes
2answers
458 views

SIM908 GPS STATUS “Location Unknown” Error

I'm using a SIM908 module on a custom board and am having trouble getting the GPS location from it. Everything else works on the module. I can send SMS, make calls and send and receive data from a ...
-3
votes
1answer
155 views

GPS is not responding [closed]

I have a skylab skg13bl GPS module. I interfaced it with arduino using the TTL, the status LED is not blinking and the GPS module is returning erroneous data. Here is my code: ...
0
votes
0answers
84 views

Raspberry Pi + GPS + Arduino Shield

I have this GPS module and an arduino shield for the raspberry pi from Cooking Hacks. See link: https://www.cooking-hacks.com/gps-shield-for-raspberry-pi My raspberry pi B+ is fully updated i have a ...
1
vote
1answer
310 views

Getting GPS coordinates with GPRS/GSM module

I'm trying to understand if I can get GPS coordinates using only a gprs/gsm module. Probably I can do it by triangulation using BTS on the terrain and based on the RF signal but is that possible? ...
0
votes
1answer
30 views

GPS Transmitter Help

I'm starting a project in which I want to be able to attach a GPS module onto a drone in case the drone falls out of sight. I have a few questions as I'm researching parts for this. My ideal specs: ...
1
vote
1answer
264 views

Help to understand/ explore small sized 3G and GPS Antenna Design

I recently came across an exciting device called Automile, from Sweden and what caught my eye is this - I am really impressed by the packaging and overall quality of hardware integration they have ...
0
votes
2answers
104 views

With regard to GPS signals, what is the significance of I-parts and Q-parts of Complex signal?

What is the significance of I-part & Q-part magnitudes and imbalances in the screenshot? They are listed next to the red Complex signal diagram. Imbalance of I-part: 4.7% Imbalance of Q-part: ...
0
votes
1answer
71 views

How can I objectively compare TCXO performance?

I would like to evaluate an alternate TCXO used in a GPS receiver circuit. Our current TCXO works good but I'm looking to test a lower cost alternate. The alternate part is Epson TG - 5035CJ / CG / ...
0
votes
0answers
54 views

Complex system circuit design and simulation

I'm building a solar powered GPS tracking device using an Ieik Mini Nano V3.0 Atmega328p microcontroller board (based on Arduino Nano), Adafruit Fona GSM module, Ublox NEO-6M GPS module. The GPS ...
0
votes
1answer
164 views

GPS gives weird characters when powering my ATMEGA328 on and off?

i got a problem with my GPS controlled by ATmega328, when i download the code using arduino ISP the GPS works fine and the lcd displays correct data, but when i remove the power from the atmega328 and ...
1
vote
1answer
745 views

How can I accurately estimate the power consumption of a GPS tracking device?

I'm building a solar powered GPS tracking device using an Ieik Mini Nano V3.0 Atmega328p Board (based on Arduino Nano), Adafruit Fona GSM module, Ublox GPS module. The GPS module will transmit ...
-1
votes
1answer
253 views

Parsing GPS data? [closed]

I wrote a code to simulate receiving NMEA string from my GPS, but faced a problem in parsing the latitude, longitude and date, i want to know what is the problem with the code . here is my code : ...
3
votes
3answers
428 views

What makes this active antenna “active?”

I'm using a external taoglas GPS/Glonass active antenna. It has a male SMA connector and I don't see where any voltage source hooks up to thing. So how is it active? Or does the power required for the ...
2
votes
1answer
349 views

Why does this BGA component have a keep-out layer?

I've pulled the Telit GE864-GPS (datasheet) from the Altium vault. The footprint has a keep-out layer, which prevents me from placing tracks to any pad without using vias. As the pitch is 2.5mm the ...
1
vote
2answers
558 views

GPS in combination with servo on Arduino

Me and my friends are building a boat which needs to steer towards certain coordinates. We have a GPS and a compass on board. We have written code which calculates the direction that the boat has to ...