Furuno GF-8801 User manual

www.furuno.com
Multi-GNSS
Disciplined Oscillator
Model
GF-8801, GF-8802,
GF-8803
Hardware Specifications
(Document No. SE19-410-006-00)

GF-8801, GF-8802, GF-8803
Hardware Specifications
SE19-410-006-00
IMPORTANT NOTICE
No part of this manual may be reproduced or transmitted in any form or by any means, electronic or
mechanical, including photocopying and recording, for any purpose without the express written permission of
the publisher, FURUNO ELECTRIC CO., LTD.
FURUNO ELECTRIC CO., LTD. All rights reserved.
Any information of this documentation shall not be disclosed to any third party without permission of the
publisher, FURUNO ELECTRIC CO., LTD.
The following satellite systems are operated and controlled by the authorities of each government.
- GPS (USA)
- GLONASS (Russia)
- Galileo (Europe)
- QZSS (Japan)
- SBAS (USA: WAAS, Europe: EGNOS, Japan: MSAS, India: GAGAN)
Thus FURUNO is not liable for the degradation of the above systems so therefore FURUNO cannot guarantee
specification based on their conditions. By solar flare or coronal mass ejection due to solar surface activity,
depending on the scale, there is a possibility that a decrease in reception sensitivity or deterioration in
precision may be temporarily observed. User is expected to be familiar with the System and make full use of it
with their own responsibility.
Although this product is paying attention to compatibility with the past products, due to the correspondence to
various additions of specifications, some actions may differ unavoidably. Regarding the specifications, the
contents described in this document are set as true, and for items not described in this document, the actual
operations of this product are set as true. For this product, if you need items compatible with past products,
please consult us before mass-producing this product.
We pay through attention about the software of this product. But, if perchance you found a bug or a trouble,
please feel free to contact us directly. We will check it, and if it is a bug, we may send you a new version with a
bug fix. If perchance we found a bug or a trouble, we may send you a new version after we contact you.
When we send you the new version software, we may ask you to update software. Therefore, we strongly
recommended being able to access to serial port of this product from outside of your product to make software
update easy. In addition, we also strongly recommend connecting between serial port of this product and
network to remote access and update software.
In this product, FURUNO can ensure safe performance only the commands and the sentences which are
written in this document or are written in the document for this product. Please do not use the commands of the
others products, otherwise this product may have troubles and FURUNO may not support about the troubles.
FURUNO may inform some internal commands for verification etc. In this case, please use the commands only
for operation test and please do not use them for technical operation.
FURUNO ELECTRIC CO., LTD. reserves the right to make changes to its products and specifications without
notice.

GF-8801, GF-8802, GF-8803
Hardware Specifications
SE19-410-006-00
Revision History
Version
Change contents
Date
0
Initial release
2019.4.18

GF-8801, GF-8802, GF-8803
Hardware Specifications
SE19-410-006-00
Table of Contents
1Outline······················································································································1
2Function Overview······································································································1
3GNSS General Performance ·························································································2
41PPS and Clock (VCLK, GCLK) Signal Specifications ······················································5
4.1 1PPS··························································································································· 6
4.2 Clock (VCLK)················································································································ 8
4.3 Clock (GCLK) ··············································································································· 9
5Time to FINE LOCK··································································································· 10
6Phase Relation between PPS and VCLK······································································· 10
7Environment Robustness Performance········································································ 11
8Operation Restriction································································································ 11
9I/O Signal Description································································································ 12
9.1 I/O Signal Description ··································································································12
9.2 Pin Arrangement··········································································································13
9.3 Alarm Signal (ALM_N)··································································································13
9.4 Lock Signal (LOCK) ·····································································································13
9.5 PPS Input Signal for External Synchronization (EPPS)·····················································14
9.6 Backup Power Supply (VBK)·························································································14
9.7 RF_COAX and RF_PIN··································································································14
10 Electrical Characteristics··························································································· 15
10.1 Absolute Maximum Rating····························································································15
10.2 Power supply ··············································································································16
10.3 Reset··························································································································17
10.4 Interface Signal ···········································································································17
10.5 Baud Rate and Error ····································································································18
10.6 UART Wake-up Timing ·································································································19
10.7 Recommended GNSS Antenna······················································································20
10.8 Antenna Amplifier Power······························································································20
11 RoHS ······················································································································21
12 Flame Retardancy Rank·····························································································21
13 FIT·························································································································· 21
14 Reliability Test··········································································································21
15 Soldering Condition··································································································21
16 Equivalent Circuit ·····································································································22
17 Mechanical Specifications··························································································22
18 Packaging················································································································24
19 Warranty·················································································································· 25
20 Special Attention ······································································································26
20.1 Precautions for Use ·····································································································26
20.2 Electronic Component··································································································26
20.3 Precautions at Mounting·······························································································26
20.4 Precautions on Industrial Property Rights ······································································27
20.5 Export Control for Security ···························································································27

GF-8801, GF-8802, GF-8803
Hardware Specifications
SE19-410-006-00
1
1 Outline
This document describes the hardware specifications of GF-8801, GF-8802 and GF-8803 which is the GNSS
Disciplined Oscillator (GNSSDO). This document uses GNSS as general term of GPS, GLONASS, Galileo and
QZSS.
2 Function Overview
This product is a GNSSDO that can provide PVT (Position, Velocity and Time) information. Figure 2-1 shows
the block level diagram. Main features are as follows:
Supports GPS, GLONASS, Galileo, QZSS (L1C/A, L1S) and SBAS.
Provides 1PPS with high accuracy and stability synchronized with GPS time or UTC time.
Provides clock signal (VCLK 10MHz) synchronized with 1PPS.
Software upgrade capability by Flash ROM.
Active Anti-Jamming capability to suppress effects of CW jammers.
Effects Multi-path mitigation.
GNSS high sensitivity.
An expensive external power supply component is unnecessary since an LDO is built in.
Coaxial connector (RF_COAX) or IF connector (RF_PIN) for GNSS signal input are selectable.
GF-8701, GF-8702, GF-8703, GF-8801, GF-8802 and GF-8803 are pin compatible.1)
Notes:
1) The specifications of power consumption, PPS and 10 MHz are different.
Multi GNSS
receiver chip
eRideOPUS 7
Serial Flash
ROM
Antenna detection
block with over current
detection function
System power supply block
ITXD
IALM_N
ILOCK
IGCLK
Reset control
block
ESD
Protector
26MHz
TCXO block
10MHz
oscillator block
External
interface
block
VCC_XO
IRXD
IEPPS
VCLK
IRST_N
TXD
ALM_N
LOCK
GCLK
RXD
EPPS
RST_N
VANT
RF_COAX
VCC VBKVANT
3.3V
RF_PIN
Figure 2-1. GF-8801/02/03 block diagram

GF-8801, GF-8802, GF-8803
Hardware Specifications
SE19-410-006-00
2
3 GNSS General Performance
These performances are measured and evaluated under the environment shown in Figure 3-1. The
measurement conditions are default setting and 25°C constant (no wind). When the signal level mask is set,
the performance is limited by the mask.
Multi-GNSS Simulator
GSS6700 RF_COAX
External LNA
Gain: 30.4dB
NF: 0.6dB
Including
Cable Loss
GF-8801
GF-8802
GF-8803
NMEA sentence
TXD
Figure 3-1. Measurement platform
Table 3-1. Time To First Fix (TTFF)
Item
Specification
Note
TTFF (HOT)
< 5 sec
[*1] [*2]
TTFF (COLD)
< 35 sec
[*1] [*3]
Table 3-2. GPS performance
Item
Specification
Note
Signal type
GPS L1C/A
Channel
MAX 12
[*4]
HOT acquisition sensitivity
> -162 dBm
[*5]
COLD acquisition sensitivity
> -148 dBm
[*6]
Tracking sensitivity
> -162 dBm
Re-acquisition sensitivity
> -162 dBm
[*7]

GF-8801, GF-8802, GF-8803
Hardware Specifications
SE19-410-006-00
3
Table 3-3. GLONASS performance
Item
Specification
Note
Signal type
GLONASS L1OF
Channel
MAX 10
[*4]
HOT acquisition sensitivity
> -158 dBm
[*5]
COLD acquisition sensitivity
> -144 dBm
[*6]
Tracking sensitivity
> -158 dBm
Re-acquisition sensitivity
> -158 dBm
[*7]
Table 3-4. Galileo performance
Item
Specification
Note
Signal type
Galileo E1B/E1C
[*8]
Channel
MAX 8
[*4]
HOT acquisition sensitivity
> -136 dBm
[*5]
COLD acquisition sensitivity
> -136 dBm
[*6]
Tracking sensitivity
> -146 dBm
Re-acquisition sensitivity
> -136 dBm
[*7]
Table 3-5. QZSS L1C/A performance
Item
Specification
Note
Signal type
QZSS L1C/A
Channel
MAX 4
[*4] [*11]
HOT acquisition sensitivity
> -136 dBm
[*5]
COLD acquisition sensitivity
> -131 dBm
[*6]
Tracking sensitivity
> -147 dBm
Re-acquisition sensitivity
> -136 dBm
[*7]
GEO satellite
Available
SVID=199 is supported.

GF-8801, GF-8802, GF-8803
Hardware Specifications
SE19-410-006-00
4
Table 3-6. QZSS L1S performance
Item
Specification
Note
Signal type
QZSS L1S
[*9] [*12]
Channel
MAX 2
[*4]
COLD acquisition sensitivity
> -130 dBm
[*6]
Tracking sensitivity
> -134 dBm
Re-acquisition sensitivity
> -130 dBm
[*7]
SLAS
Available
[*10]
Table 3-7. SBAS performance
Item
Specification
Note
Signal type
SBAS L1C/A
SVID=120 to 138 are supported. [*9]
Channel
MAX 2
[*4] [*13]
Acquisition sensitivity
> -130 dBm
[*6]
Tracking sensitivity
> -139 dBm
Reacquisition sensitivity
> -130 dBm
[*7]
[*1] These are specified in the measurement environment shown in Figure 3-1. Simulator output level is set to -130 dBm.
[*2] The time from sending HOT restart command to re-acquisition
[*3] The time from sending COLD restart command to re-acquisition
[*4] Up to 32 channels are available for whole GNSS.
[*5] After sending HOT restart command during satellite receiving
[*6] After sending COLD restart command during satellite receiving
[*7] Within 250 seconds after the last signal receiving
[*8] Due to the composition of the message broadcast by Galileo, TTFF of Galileo may take about 100 seconds.
[*9] Only one of QZSS L1S and SBAS L1C/A can be used. They cannot be received at the same time.
[*10] SLAS correction is performed to GPS and QZSS.
[*11] Up to 4 satellites can be received simultaneously among 193, 194, 195, 196 and 199.
[*12] Up to 2 satellites can be received simultaneously among 183, 184, 185, 186 and 189.
[*13] WAAS, MSAS, EGNOS and GAGAN are supported.

GF-8801, GF-8802, GF-8803
Hardware Specifications
SE19-410-006-00
5
4 1PPS and Clock (VCLK, GCLK) Signal Specifications
The follow is the specifications of 1PPS and clock (GCLK, VCLK). Please refer to the eSIP Protocol
Specification for switching setting etc. The performance described in this chapter is measured and evaluated
under the environment shown in Figure 4-1 and 4-2 below. In the absence of any notes, measurement
conditions are default setting, open sky, constant at 25 degree (no wind).
GF-880X
Evaluation Board
GNSS rooftop
antenna
Universal counter
53132A
Reference GNSS DO
[*1] 1PPS
1PPS
10MHz
CH1
CH2
REF IN
phase
delay
Figure 4-1. 1PPS measurement environment
GF-880X
Evaluation Board
GNSS rooftop
antenna
Universal counter
53132A
Reference GNSS DO
[*1]
VCLK,GCLK
10MHz
10MHz
CH1
REF IN
clock
Figure 4-2. Clock measurement environment
[*1] GNSSDO equipped with rubidium oscillator calibrated by USNO (United States Naval Observatory).
The definition of the terms is as follows.
MAX|TE|: It is a maximum time error (absolute value) of 1PPS for UTC time.
MTIE: Maximum time interval error. It is a relative MIN-MAX value of 1PPS.
SDEV, TDEV: Standard deviation and Time deviation. They show 1PPS fluctuation.

GF-8801, GF-8802, GF-8803
Hardware Specifications
SE19-410-006-00
6
4.1 1PPS
Table 4.1-1. 1PPS general specifications
Item
Specification
Note
Nominal frequency
1 Hz
Duty cycle
50 %
[*1]
Synchronization target
GPS, UTC
[*2]
[*1] The pulse width can be changed by PPS command. Please refer to the eSIP protocol specifications for details.
[*2] 1PPS is output in synchronization with GPS time or UTC time. Please refer to the eSIP protocol specifications for details.
Table 4.1-2. 1PPS output specifications [FINE LOCK]
Item
Specification
Note
1PPS accuracy
(MAX|TE|)
< 40 nsec
MIN-MAX value from UTC time / [*1][*2]
1PPS stability
(Standard deviation)
< 4.5 nsec
@ 1sigma / [*2][*3]
1PPS stability
(Time deviation)
G.8272 PRTC-B
compliant
@ 1sigma / [*2][*4][*6]
1PPS stability
(MTIE)
G.8272 PRTC-B
compliant
Relative MIN-MAX value / [*2][*5][*6]
[*1] It is necessary to adjust cable offset beforehand. In addition, it may be necessary to adjust the hardware offset of the entire
device incorporating this product.
[*2] After SS mode or CSS mode for more than 24 hours, or after TO mode via it
[*3] GF-8701 uses a TCXO as an internal oscillator. Please pay attention to the installation environment since it is particularly
susceptible to wind and temperature.
[*4] TDEV of G.8272 PRTC-B compliant means that it meets the following specifications.
Time deviation limit [nsec]
Observation interval τ [sec]
1
1<τ<100
0.01τ
100<τ<500
5
500<τ<100000
[*5] MTIE of G.8272 PRTC-B compliant means that it meets the following specifications.
MTIE limit [nsec]
Observation interval τ [sec]
0.275τ + 25
1<τ<55
40
55<τ
[*6] G.8272 PRTC-B compliant is GF-8802 and GF-8803 only. TDEV and MTIE of GF-8801 is G.8272 PRTC-A compliant.