Huahuan Electronics HX.PTP-GM02 User manual

HX.PTP-GM02
Suction-window-mount
GNSS based
Indoor PTP Grandmaster

HX.PTP-GM02
Suction-window-mount
GNSS based
Indoor PTP Grandmaster
User’s Manual
Beijing Huahuan Electronics Co., Ltd.
Version 1.0 (Sept. 2018)

Copyright Notice
The intellectual property rights of all parts of this product,
including accessories etc., are owned by Beijing Huahuan Electronics
Co., Ltd. (Beijing Huahuan for short). Without prior written consent of
Beijing Huahuan, no part of this document may be reproduced or
transmitted in any form or by any means. The information in this
document, including product specifications and information, is subject
to change without notice. For information related, please consult Beijing
Huahuan.
Copyright © Beijing Huahuan Electronics Co., Ltd. 2013 All rights
reserved
Model: HX.PTP-GM02
Product Name: GeckoSynco
Description: Suction-window-mount GNSS based Indoor PTP Grandmaster
Manual Version: 1.0
Release Date: Sept. 2018
BEIJING HUAHUAN ELECTRONICS Co., LTD.
Address: No.26, Shangdi 6th Street, Haidian District, Beijing, 100085
P.R. China
Tel: [phone]
Fax: [phone]
Website: www.huahuan.com
E-mail: [e-mail]

Contents
1.

OVERVIEW.........................................................................1
1.1. Features...........................................................................................1
1.2. Ordering Information....................................................................2
2.

TYPICAL APPLICATION .....................................................2
2.1. IEEE-1588V2 Grandmaster Clock...............................................3
2.2. 1PPS+ToD Scenario.......................................................................6
2.3. GeckoSynco as NTP Server...........................................................7
3.

ARCHITECTURE AND INSTRUCTIONS.............................8
3.1. Structure.........................................................................................8
3.1.1. System LED.............................................................................9
3.1.2. Electrical ETH Port................................................................10
3.1.3. Optical Port............................................................................12
3.1.4. 1PPS+TOD Port.....................................................................13
3.1.5. The Dip Switches...................................................................14
3.2. Power Supply................................................................................14
3.3. Functional Descriptions...............................................................15
3.3.1. Time Synchronization............................................................15
3.3.2. Synchronous Ethernet (SyncE)..............................................16

3.3.3. PTP Grandmaster Clock ........................................................17
3.3.4. SNMP Agent..........................................................................18
4.

INSTALLATION AND OPERATION ..................................18
4.1. Location Selection........................................................................18
4.2. Installation....................................................................................20
4.2.1. Mounting Procedure ..............................................................20
4.2.2. Connecting the Ethernet and PoE Adaptor............................21
4.2.3. Connecting the Optical Fiber.................................................21
4.2.4. Connecting the 1PPS+ToD Cable..........................................21
4.3. Setting Operating Parameters.....................................................22
5.

DEVICE MANAGEMENT....................................................22
6.

SOFTWARE USAGE..........................................................23
6.1. Web Server Interface...................................................................23
6.1.1. Web Server Login..................................................................23
6.1.2. Version Enquiry and IP Setting .............................................23
6.1.3. Online Upgrade......................................................................24
6.1.4. Configuring the Time Mode ..................................................25
6.1.5. GNSS Info Enquiry................................................................27
6.1.6. PTP Parameter Setting...........................................................28
6.1.7. 1PPS+ToD Setting.................................................................29
6.2. CLI Description............................................................................31
6.2.1. CLI Login ..............................................................................31

6.2.2. Version Check........................................................................31
6.2.3. IP Related Settings.................................................................31
6.2.4. Check 1PPS Settings..............................................................31
6.2.5. Setting 1PPS Duty Cycle.......................................................31
6.2.6. Setting 1PPS Delay................................................................32
6.2.7. Restore Factory Settings........................................................32
7.

TROUBLE SHOOTING.......................................................32
8.

SPECIFICATIONS..............................................................33
8.1. Satellite..........................................................................................33
8.2. Protocols........................................................................................34
8.3. Ethernet Electrical Interface.......................................................34
8.4. Ethernet Optical Interface...........................................................34
8.5. 1PPS+ToD Interface....................................................................35
8.6. Management.................................................................................35
8.7. Physical/Electrical/Environment ................................................35

List of Figures
Figure 2-1 Enterprise smallcell synchronization scheme .....................5
Figure 3-1 HX.PTP-GM02 diagram.....................................................8
Figure 3-2 HX.PTP-GM02 bottom panel .............................................9
Figure 3-3 RJ45 connector diagram....................................................10
Figure 3-4 RJ-11 Pin numbering order...............................................13
Figure 3-5 Front and rear panel of the PoE adaptor............................15
Figure 4-1 Sky view clearance............................................................19
Figure 4-2 Installation schematic........................................................20
Figure 6-1 Change username & password..........................................23
Figure 6-2 System info page...............................................................24
Figure 6-3 Upgrade interface..............................................................25
Figure 6-4 Fixed time mode ...............................................................26
Figure 6-5 3D search time mode.........................................................27
Figure 6-6 GNSS information ............................................................28
Figure 6-7 PTP settings ......................................................................29
Figure 6-8 1PPS+ToD settings...........................................................30

List of Tables
Table 1-1 HX.PTP-GM02 ordering information..................................2
Table 3-1 Color code of the SYS LED.................................................9
Table 3-2 Color code of the L/A and LOS LEDs...............................10
Table 3-3 RJ-45 pin definition............................................................10
Table 3-4 1PPS+ToD port pin definition............................................13
Table 3-5 Dip switch functions...........................................................14
Table 7-1 Common faults and solutions.............................................32

Beijing Huahuan Electronics Co., Ltd
1
1. .

 O Ov ve er rv vi ie ew w
HX.PTP-GM02, codenamed GeckoSynco, is a high precision timing source
based on Global Navigation Satellite Systems (GNSS). What separates
GeckoSynco from similar products in the market is its Peek2Sync design. With
everything integrated into a small box, it is to be suction-mounted inside a
building on to a window with only a partial view of the sky. This design
eliminates the need for an outdoor satellite antenna, thus without associated
lightning and other environment protection concerns, as well as much simplifies
the site selection and installation process.
HX.PTP-GM02 supports IEEE-1588V2 precision timing protocol (PTP), to
be used as a grandmaster (GM) in a PTP domain. Multiple PTP profile choices
are built-in, useful for applications in telecommunications, electrical systems, and
other scenarios where precision timing is needed.
Apart from being a PTP grandmaster, HX.PTP-GM02 also has a built-in
NTP server, as well as an output port for 1 pulse-per-second and time-of-day
(1PPS+ToD) signals used by different end equipment for timing reference.
1.1. Features
Indoor device with creative Peek2Sync suction window mount design (Pat.
No. ZL201520849428.3);
GNSSNote1based synchronization, selectable among GPS, GLONASS or
Beidou. Integrated antenna;
Single-SV timing mode supported, only partial sky view required, ±100ns
timing accuracy;
PTP Grand-Master, NTP Server, 1PPS+ToD output with adjustable cable
length delay compensation;
SyncE function, the clock synchronization between devices in Ethernet is
realized;
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1PPS loopback distance measurement;
High stability OCXO based, better than 1ppb holdover performance;
Multiple PTP profile support, PnP operation within selected profile;
10/100/1000Base-T, PoE powered, low power consumption;
100/1000 Base-X Fiber optic Ethernet interface;
Web server, SNMP, CLI configuration and management interfaces.
Note1：GPS i s currentl y the m ost m ature G N SS system. A l l the preci si on spec ifications
given in this Manual are based on GPS. They may differ when other GNSS system is
used.
1.2. Ordering Information
HX.PTP-GM02 ordering information is given in Table 1-1.
Table 1-1 HX.PTP-GM02 ordering information
Model Description
HX.PTP-GM02/GP
HX.PTP-GM02/GN
HX.PTP-GM02/BD
Main device×1
GP—GPS, GN—GLONASS, BD—
Beidou
Accessary: PoE Power adaptor×1
(specify power cord for your country),
RJ45 plug×3, 6-pin RJ12 plug×1,
suction cup×4 (screwed onto the main
device)
2
2. .

 T Ty yp pi ic ca al l A Ap pp pl li ic ca at ti io on n
The HX.PTP-GM02 device receives satellite signals from various GNSS
systems, acquires time synchronization to International Atomic Time (TAI)
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within sub-µs accuracy, and provides timing reference to various application
systems. Supported protocols include IEEE-1588V2, 1PPS+ToD, and Stratum-1
NTP server.
2.1. IEEE-1588V2 Grandmaster Clock
In the fields of telecommunications, electrical networks, measurement
instruments, and industrial automation, time synchronization and/or frequency
syntonization among individual nodes are key enablers for the normal functioning
of the connected systems. In the past couple of decades, such system connections
are quickly evolving from previous generations of diverse networking
technologies into Ethernets. While a unified Ethernet networking technology
improves a lot of aspects of the applications, one particular property of current
Ethernet systems, namely timing opaqueness resulting from packet delay
variations and asynchronous physical links, needs to be dealt with to achieve sub-
µs synchronization. IEEE-1588 precision timing protocol was specifically
designed for high precision synchronization over packet based networks,
especially Ethernet networks.
In a PTP timing domain, one or several backup grandmaster clocks are
needed to provide necessary timing reference. Since the requirements for timing
differ in different industries, each industry specifies a separate profile based on
the overall standard of the IEEE-1588V2. For example, in telecommunications,
ITU-T G.8265.1 and G.8275.1 specify respectively network syntonization and
synchronization profiles. Grandmaster clocks compliant to these profile standards
are called telecom grandmasters, or T-GM.
Supported by hardware and software code sign, the HX.PTP-GM02 can
operate under a set of pre-defined profiles, so that it can be readily used as a GM
in a number of applications. Its usage is exemplified in the following pages,
where a GeckoSynco provides timing reference for enterprise smallcells in 4G/5G
mobile networks.
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4G/5G base stations, including smallcells, require sub-µs timing
synchronization. When Ethernet becomes the preferred technology for backhaul
transmission, PTP is considered one of the main synchronization techniques. In
principle, the complete backhaul network could constitute a single timing domain.
In such a scheme, a T-GM is placed at the mobile core, and timing is distributed
to every station through the vast expanse of complete set of core, aggregation, and
access networks. This arrangement, however, has two problems.
Problem No.1, it is necessary that every node in the entire carrier’s backbone
packet transport network is PTP ready. The fact is that most of the legacy network
equipment does not support PTP. It will need an enormous capital investment to
replace all the equipment just for synchronization, while they are still quite
capable for all the other functionalities needed for mobile backhaul operations.
When smallcells are concerned, the backhaul may not entirely be owned by the
carrier, part of the transport could be carried by the public internet. It is simply
not practical to upgrade the entire internet to support PTP.
Problem No.2, even if all the nodes support PTP, the end results may not be
adequate if too many intermediate nodes are crossed by the packets, between the
end base station and the T-GM at the core network. This is because each node will
contribute some phase error, causing degradation to the end-to-end clock quality,
while 4G/5G mobile technology requirement for timing accuracy is too stringent
to satisfy. Another drawback is that the added PTP packets to and from every
node in the network dramatically increases the total load of the network
bandwidth.
The more appropriate arrangement is to put a number of T-GM’s at the edge
of the network, closer to the base stations and smallcells. In this way, PTP timing
domains are localized, the rest of the network just provides necessary bandwidth
for data transmission, which most of existing backbone networks and even public
internet are capable of. One of the key requirements for this arrangement is the
availability of high quality, low cost, easy to install GM devices. The
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GeckoSynco is particularly suited in this regard.
In the scenario shown in Figure 2-1, a HX.PTP-GM02 is running the ITU-T
G.8275.1 profile. It is installed within an enterprise building as the local T-GM,
constitutes a PTP domain with all the smallcells and the enterprise LAN devices.
Smallcells get their timing synchronization from this PTP domain, and the public
internet provides backhaul connection to the carrier network. PTP packets are
local to the enterprise LAN, no PTP support is required in other parts of the
backhaul.
RAN NC
RAN NC
RAN NC
Carrier Network
Internet
GeckoSynco
Smallcell
Smallcell
Smallcell
Smallcell
Figure 2-1 Enterprise smallcell synchronization scheme
Because GeckoSynco uses our Peek2Sync design, it can be easily sucked
onto the inside of a window with resonable sky view. Unlike most GPS clocks,
GeckoSynco do not require an outdore satellite antenna, thus avoids the need for
site selection, mast installation and fixation, lightning protection, and other
precautions associated with an outdoor antinna. The indoor condition is also a lot
less harsh in terms of temperature, humidity, and other environmental factors,
which is more faverable for longer operating life, stablilty and realibility.
The integrated design means that the connection between the GeckoSynco
and the network equipment, which is typically in the equipment room at a fixed
location far from the rooftop, is Ethernet. This meas the distance between the
window site and the equipment room can be separated up to 100 meters. Much
longer distance may be reached with optical Ethernet. This is in contrast with
clocks using analog coax cable to connect to the rooftop antenna unit. Outdoor
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antenna is needed because the attenuation introduced by the coax cable requires as
good reception as possible. Still the very weak satellite signal limits the cable to
just a few dozen meters, and thick coax cable and an intermediate active amplifier
is usually required for longer reach, aggravating the installation task. This
distance limitation also complicates the equipment room site selection.
2.2. 1PPS+ToD Scenario
In many applications, PTP is not used or supported. Many pre-PTP devices
requiring time and frequency synchronization have 1PPS and ToD inputs for
timing reference. Such devices include basestations, smallcells, telprotection
equipment in power networks. Even in PTP networks, many IEEE-1588V2
compliant network nodes such as Ethernet switches, routers, PTN transmission
equipnent, have their own 1PPS+ToD inputs for timing reference, and then act as
GM in the domain. In such applications, the GeckoSynco does not run PTP
protocol, but output 1PPS+ToD signal to those nodes.
Let’s again take the example of the enterprise smallcell network depicted in
Figure 2-1. The Ethernet LAN switch here is a PTP boundery clock that has a
1PPS+ToD input as its timing reference, and act as the T-GM in the domain. The
role of the GeckoSynco in the diagram is no longer a PTP GM, but provides
timing reference gained from GPS satellite through its 1PPS+ToD output. Though
not much different from the previous example in terms of equipment used,
installation simplicity, as well as performance, it does have an added benifit: a
much longer distance buget between the GeckoSynco and the equipment room
without resort to optical fibers. This is because the 1PPS+ToD cable can be 10
times longer than the 100 meters limit of Ethernet. When distance budgt exceeds
100 meters, this configuration may be considered. The 1PPS+ToD cable is
usually also made with CAT5 cable just like the Ethernet cable, but the plug used
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on the GeckoSynco side is a 6-pin RJ12 rather than usual RJ45. Connector on the
othere end of the cable needs to match the specification of the matching input port
on the Ethernet switch.
It should be noted here that the use of 1PPS+ToD signal as time reference
has one precaution to be considered. Different from bidirectional PTP protocol
exchanges between the T-GM and the switch, which automatically calculates the
cable delay, the 1PPS+ToD is single directional, and thus the cable delay cannot
be automatically adapted. When phase error needs to be within a few
nonoseconds, installation engnieer needs to know the cable delay and compensate
through the management interface provided by the GeckoSynco software. The
1PPS signal in a CAT5 cable is delayed about 5.02ns/meter. The web interface for
entering cable delay is described in section 6.1.7. The GeckoSynco can actually
measure the delay during installation by putting a loopback socket at the other end
of the cable, without carefully measuring the cable length.
2.3. GeckoSynco as NTP Server
Most networked computers get their time from NTP servers. There are many
NTP servers on the internet. For example, the IP address for one of the United
States NIST (National Institute of Standards and Technology) NTP servers is
129.6.15.28.
However, not every computer network is connected to the internet. For
example, many private LANs are physically separated from the outside world for
security concerns. Computers in these isolated networks still need to keep correct
time. A common solution is to setup a local NTP server within the network.
The GeckoSynco can be used as the local NTP server in such networks.
GeckoSynco synchronizes to the TAI/UTC international standard time through
GNSS satellites, with sub-microsecond accuracy. The built-in NTP service makes
it an ideal stratum-1 NTP server. Without congestions and the resulting packet
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delay variations, a computer can achieve higher time accuracy from a local NTP
server than that from a faraway NTP server on the internet. This makes
GeckoSynco also a good choice for networks requiring better timing even if it
does have access to the internet.
3
3. .


A Ar rc ch hi it te ec ct tu ur re e a an nd d I In ns st tr ru uc ct ti io on ns s
3.1. Structure
HX.PTP-GM02 is depicted in the following diagram:
GeckoSynco
SYS LED
Suction
Cup
Figure 3-1 HX.PTP-GM02 diagram
On the front surface, a 3-color LED is used to indicate the operational status
of the device, as described in Table 3-1.
Four suction cups are screwed into the corners on the back side. These
suction cups can be easily pressed to mount the device onto a clean smooth
window glass.
Three signal ports and a dip switch are placed on the front panel of the
device, as shown in Figure 3-2. Two LEDs within the Ethernet port are used to
indicate the status of the electrical Ethernet connection, while the LEDs along the
optical port indicate the status of the optical Ethernet. Descriptions of these ports
8HX.PTP-GM02 IEEE-1588 Grandmaster Clock V1.0

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and the dip switch are given in sections 3.1.2 through 3.1.5.
1 2
ON
1 PPS+TOD ETH
L/A
LOS
GX
Figure 3-2 HX.PTP-GM02 bottom panel
Note: As a PoE powered device (PD), DC 48V power is provided to HX.PTP-
GM02 through the Ethernet port. There is no separate power input.
3.1.1. System LED
The SYS LED on the front face is used to indicate the operational status
of the GeckoSynco device, as described in the following table:
Table 3-1 Color code of the SYS LED
LED Color
Code Descriptions
SYS
Red
Steady: Loss of satellite reception, unsynchronized
Blinking: Loss of satellite reception, Holdover
Green
Blinking: Normal, good for timing source
Yellow
Steady: Booting
Blinking: Synchronization acquisition
Off
Unpowered or power failure
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Table 3-2 Color code of the L/A and LOS LEDs
LED Color
Code Descriptions
L/A Green On: Ethernet optical port Link up
Blinking: Date transmitting in Ethernet optical port
Off: Ethernet optical port Link down
LOS Red On: no optical signal received in Ethernet optical port
Off: optical signal received in Ethernet optical port
3.1.2. Electrical ETH Port
The 8-pin RJ45 socket marked ETH on the bottom panel of the HX.PTP-
GM02 is the 10/100/1000M Base-T Ethernet port. It is used for PTP protocol
packets, management, as well as power input for the device.
1. 10/100/1000 Base-T Port
Being a standard IEEE 802.3 10/100/1000 Base-T Auto mode Ethernet port,
the RJ45 connector diagram is shown in Figure 3-3 and pin definition for the
RJ45 is given in Table 3-3. Note that it is compatible with PoE standard.
1
8
Figure 3-3 RJ45 connector diagram
Table 3-3 RJ-45 pin definition
Pin
1
2
3
4
5
6
7
8
Eth. Sig.
tip
ring
tip
tip
ring
ring
tip
ring
10 HX.PTP-GM02 IEEE-1588 Grandmaster Clock V1.0