UNICORECOMM UM4B0 User manual

UM4B0
GPS/BDS/GLONASS/Galileo Four-
System Undeca-Frequency High
Precision RTK Module

Revision History
Version
Revision History
Date
Ver. 1.0
First Edition
Feb. 2017
R3.1
Add the related description to clarify
the VCC restrictions
2019-08-22
Chapter 2.2: add the working current
info of No.17 pin
2019-09-18
Disclaimer
Information in this document is subject to change without notice and does not
represent a commitment on the part of Unicore Communications, Inc. 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 a duly authorized representative of Unicore Communications, Inc.
The information contained within this manual is believed to be true and correct at the
time of publication. © Copyright 2009-2019 Unicore Communications, Inc. All rights RSV.
R3.2

Foreword
This <User Manual> offers you information in the features of the hardware, the
installation, specification and use of Unicore UM4B0 product.
For the generic version of this manual, please refer to different part of the manual according to
your purchased product configuration, concerning CORS, RTK and Heading.
Readers it applies to
This <User Manual> is applied to the technicists who know GNSS Receiver to some
extent but not to the general readers.

I
Contents
1INTRODUCTION...................................................................................1
1.1 OVERVIEW........................................................................................................................................ 1
1.2 KEY FEATURES................................................................................................................................... 1
1.3 TECHNICAL SPECIFICATIONS ................................................................................................................. 2
1.4 INTERFACES ...................................................................................................................................... 3
2HARDWARE.........................................................................................4
2.1 DIMENSIONS..................................................................................................................................... 4
2.2 PIN DEFINITION AND INS COORDINATE SYSTEM (TOP VIEW）................................................................... 5
2.3 ELECTRICAL SPECIFICATIONS................................................................................................................. 7
2.4 OPERATION CONDITION ...................................................................................................................... 8
2.5 PHYSICAL SPECIFICATIONS.................................................................................................................... 8
3HARDWARE DESIGN ............................................................................9
3.1 DESIGN IN CONSIDERATIONS ................................................................................................................ 9
3.2 UM4B0 REFERENCE DESIGN ............................................................................................................. 10
3.3 PINS.............................................................................................................................................. 11
3.4 PCB PACKAGING ............................................................................................................................. 13
3.5 RESET SIGNAL.................................................................................................................................. 13
3.6 ANTENNA....................................................................................................................................... 13
4INSTALLATION AND CONFIGURATION ...............................................14
4.1 ESD HANDLING PRECAUTIONS ........................................................................................................... 14
4.2 HARDWARE INSTALLATION................................................................................................................. 15
4.3 START UP....................................................................................................................................... 17
4.4 CONFIGURATION AND OUTPUT........................................................................................................... 17
4.4.1 Operation Procedures ............................................................................................................. 18
5CONFIGURATION COMMANDS..........................................................19
5.1 RTK REFERENCE STATION CONFIGURATION .......................................................................................... 21
5.2 RTK ROVER CONFIGURATION............................................................................................................. 22
5.3 MOVING BASE CONFIGURATIONS........................................................................................................ 22
5.4 HEADING CONFIGURATION ................................................................................................................ 22
6ANTENNA DETECTION .......................................................................23
7INERTIAL NAVIGATION ......................................................................23
8FIRMWARE UPGRADE........................................................................24
9PRODUCTION REQUIREMENT............................................................26
10 PACKAGING....................................................................................27

UM4B0 User Manual
1
1Introduction
1.1 Overview
UM4B0 is the high precision positioning and heading RTK module developed by Unicore
Communications, targeting light Robots, UAVs, intelligent vehicles, GIS information
collection, etc.
By employing a single UC4C0(432 channel tracking) baseband chip and a single RF chip,
using single-sided SMD packaging, UM4B0 can achieve smallest size(30x40mm) among
industry with high accuracy heading and positioning output. . It can simultaneously
track BDS B1/B3 + GPS L1/L2 + GLONASS L1/L2+Galileo E1. It can maintain excellent
application experience even in the most challenging environments such as urban
canyons, by deploying anti-interference function block and on board MEMS device.
Figure 1-1 UM4B0 Module
1.2 Key Features
•30*40mm, smallest multi-system multi-frequency high precision module
•Support GPSL1/L2/L5+GLONASSL1/L2+BDS B1/B2/B3+GalileoE1/E5a/E5b
•Based on 432 channel Nebulas-II GNSS SoC chip
•20Hz update rate
•Instant RTK initialization and long-distance RTK
•Enhanced multi-system multi-frequency RTK technology, JamShield Adaptive
narrow-band anti-interference and U-AutoAlign multi-path mitigation
•On board MEMS integrated navigation, support improved U-Fusion integrated
navigation algorithm
•Support odometer input and external high-performance IMU interface*
•SMD packaging

2
1.3 Technical Specifications
Table 1-1 Performance Specifications
Channels
432 channels, based on Nebulas-II SoC
chip
Initialization
time
<5s (typical)
Frequency
GPS L1/L2/L5
BDS B1/B2/B3
GLONASS L1/L2
Galileo E1/E5a/E5b
Initialization
reliability
>99.9%
Single point
positioning
Horizontal：1.5m
Time to First
Fix (TTFF)
Cold start<25s
Vertical：3.0m
Reacquisition
<1s
DGPS(RMS)
Horizontal：0.4m
Correction
RTCM 2.3/3.0 /3.2
Vertical：0.8m
RTK(RMS)
Horizontal：10mm+1ppm
Data Output
NMEA-0183, Unicore
Binary
Vertical：15mm+1ppm
Update Rate
20Hz
Heading
Accuracy (RMS)
0.2 degree@1 m baseline
Time accuracy
(RMS)
20ns
Velocity Accuracy
(RMS)
0.03m/s
Power
Consumption
1.7W
Dimension
30×40×4 mm
Table 1-2 Functional Ports
3x UART, 1xI2C, 1x SPI (LV-TTL)
1x1PPS（LV-TTL）
1x Event input
Note: * represents optional configuration

UM4B0 User Manual
3
1.4 Interfaces
RF in
RF
Fron
tend
SAW
Filter
Nebulas-II
MEMS Chip
UART
SPI
GPS
BDS
GLO
GAL
SBAS
Interface Event
TCXO
I2C
ANT_PWR
PPS
Figure 1-2 Block Diagram
1. RF Part
The receiver gets filtered and enhanced GNSS signal from the antenna via a coaxial
cable. The RF part convert the RF input signals into the IF signal, and convert IF analog
signal into digital signals required for Nebulas II die (UC4C0).
2. Nebulas-II SoC（UC4C0）
Nebulas-II (UC4C0) is Unicore’s new generation high precision GNSS SoC with 55nm low
power design, supports up to 12 digital intermediate frequency or 8 analog
intermediate frequency signals, which can track 12 navigation signals with 432 channels.
3. MEMS
By deploying anti-interference function block and on-board MEMS device, UM4B0 can
maintain excellent application experience even in the most challenging environments
such as urban canyons.
4. 1PPS
UM4B0 outputs 1 PPS with adjustable pulse width and polarity.
5. Event
UM4B0 provides 1 Event Mark Input with adjustable pulse width and polarity.

4
2Hardware
2.1 Dimensions
Table 2-1 Dimensions
Symbol
Value (mm)
Tolerance (mm)
A
40.00
-0.2 +0.5
B
30.00
±0.2
C
4.00
±0.2
D
1.58
±0.1
E
1.27
±0.1
PIN
1.07
Figure 2-1Mechanical Dimensions

UM4B0 User Manual
5
2.2 Pin Definition and INS Coordinate System (Top View）
Figure 2-2 UM4B0 Pin Diagram
Table 2-2 Pin Definition
No.
Pin
I/O
Description
1
GND
-
Ground
2
ANT_IN
I
GNSS antenna signal input
3
GND
-
Ground
4
GND
-
Ground
5
ANT_PWR
I
GNSS antenna power supply
6
GND
-
Ground
7
ANT_NLOD
O
GNSS antenna open circuit indicator
1: normal
0: antenna is open circuit
8
ANT_FFLG
O
GNSS antenna short circuit indicator
1: normal
0: antenna is short circuit
9
GND
Power
DGND/GND
10
RSV
-
RSV
X
Y

6
No.
Pin
I/O
Description
11
RSV
-
RSV
12
RSV
-
RSV
13
RSV
-
RSV
14
GND
-
Ground
15
SPEED
I
odometer- pulse
16
FWR
I
odometer- direction
17
V_BACKUP
I
When the main power supply of the
module VCC is cut off, V_BCKP supplies
power to RTC and SRAM. Level
requirements: 2.0~ 3.6 V, and the working
current is about 10uA. Can be suspended
without using the hot start function
18
GND
-
Ground
19
PVT STAT
O
PVT positioning indicator, active-high. The
module outputs high level when positioning
and outputs low level when no positioning
is proceeded.
20
GPIO2
I/O
Common IO
21
RSV
-
RSV
22
FRESET_N
I
Reset to factory default (clear all user
settings), LVTTL active-low, press longer
than 5 seconds
23
ERR_STAT
O
Abnormal indicator, active-high. When the
RTK solution is fixed, it outputs high level,
alternatively outputs low level when the
module completes the self-diagnosis.
24
RTK_STAT
O
RTK positioning indicator, active-high.
When the self-diagnosis of the module
system fails, it outputs high level,
alternatively outputs low level when it’s in
other positioning states or no positioning is
proceeded.
25
GND
-
Ground
26
SPI_MISO
I
SPI data input
27
SPI_MOSI
O
SPI data output
28
SPI_CLK
O
SPI clock
29
SPI_SS0
O
SPI chip select 0
30
SPI_SS1
O
SPI chip select 1
31
3.3V_VCC
Power
Power Supply (+3.3V)
32
3.3V_VCC
Power
Power Supply (+3.3V)
33
GND
-
Ground
34
GND
-
Ground
35
TXD1
I/O
COM 1 transmit
36
RXD1
I
COM 1 receive

UM4B0 User Manual
7
No.
Pin
I/O
Description
37
TXD2
O
COM 2 transmit
38
RXD2
I
COM 2 receive
39
TXD3
O
COM 3 transmit
40
RXD3
I
COM 3 receive
41
I2C_SDA
I/O
I2C data
42
I2C_SCL
I/O
I2C clock
43
GND
-
Ground
44
PPS
O
Pulse per second
45
EVENT
I
Event Mark
46
RST_N
I
Fast reset, will not clear user
configurations. active Low, > 5 ms
47
GND
-
Ground
48
RSV
-
RSV
49
RSV
-
RSV
50
RSV
-
RSV
51
RSV
-
RSV
52
GND
-
Ground
53
RSV
-
RSV
54
RSV
-
RSV
55
GND
-
Ground
56
RSV
I
RSV
57
GND
-
Ground
58
GND
-
Ground
59
RSV
I
RSV
60
GND
-
Ground
2.3 Electrical Specifications
Table 2-3 Absolute Maximum Ratings
Item
Pin
Min
Max
Unit
Power Supply (VCC)
Vcc
-0.3
3.6
V
Voltage Input
Vin
-0.3
VCC+0.2
V
LNA Input
ANT_PWR
-0.3
6
V
GNSS Antenna Signal Input
ANT_IN
-0.3
ANT_PWR
V
VCC Ripple (Rated Max.)
Vrpp
0
50
mV
Voltage Input (pins other than
RXD1, RXD2,RXD3)
Vin
-0.3
3.6
V
Maximum ESD stress
VESD(HBM)
±2000
V

8
2.4 Operation Condition
Table 2-4 Operation Condition
Item
Pin
Min.
Typical
Value
Max.
Unit
Condition
Power Supply (VCC)
Vcc
3.2
3.3
3.6
V
Pulse current*
Iccp
8.8
A
Vcc = 3.3 V
LOW Level Input
Voltage
Vin_low_1
-0.3
VCC*0.3
V
High Level Input
Voltage
Vin_high_1
VCC*0.7
VCC+0.3
V
LOW Level Output
Voltage
Vout_low
0
0.45
V
Iout= 4 mA
High Level Output
Voltage
Vout_high
VCC-0.45
VCC
V
Iout =4 mA
Antenna Gain
Gant
20
30
36
dB
Noise Figure
Nftot
2.5
3
3.5
dB
LNA Input
ANT_PWR
3.3
5
5.5
V
< 100mA
Operating
Temperature
Topr
-40
85
°C
Power Consumption
P
1.5
1.8
2.0
W
NOTE: Because of the capacitance inside the product, inrush current will occur when the
power is turned on. Evaluate in real environment to check the effect of inrush current
on supply voltage drop.
2.5 Physical Specifications
Table 2-5 Physical Specifications
Size
30×40×4 mm
Weight
8g
Temperature
Working : -40℃～+85℃
Storage: -55℃～+95℃
Humidity
95% No condensation
Vibration
GJB150.16-2009，MIL-STD-810
Shock
GJB150.18-2009，MIL-STD-810

UM4B0 User Manual
9
3Hardware Design
3.1 Design in Considerations
To make UM4B0 to work properly, you need to properly connect the following:
The module VCC power-on has good monotone, the initial level is lower than 0.4V,
and the undershoot and ringing should be guaranteed within 5% VCC
Provide reliable power to the VCC pin
Connect all the GND pins to ground
Connect VBAT pin to a 3.0V power supply
Connect ANT_IN signal to the antenna, and make sure the 50 ohm impedance
matching
Connect ANT_PWR to +3.3~5.5 V voltage, then supply +3.3~5.5 V feed to the
antenna through ANT_IN
Ensure COM1 is connected to a PC or an external processor, users can use this serial
port to receive position data. COM1 is also necessary for firmware upgrades
Properly connect the module’s reset pin FRESET_N to ensure reliable reset of the
module. It will restore to manufactory configuration.
When ANT_NLOD, ANT_FFLG and antenna detection indication signal are connected,
the IO of client MCU terminal is required as input without any pull-up/down.
In order to obtain proper performance, special concerns should be paid during the
design:
Power supply: Stable and low ripple power is necessary for good performance.
Make sure the peak to peak voltage ripple does not exceed 50mVpp. It is
recommended to use a power chip with current output capacity greater than 2A to
power the board.
-Using LDO to ensure the purity of power supply
-Try to place LDO close to the module in layout
-Widening the power circuit or use copper pour surface to transmit current
-Avoid walking through the high–power or high inductance devices such as
magnetic coil

10
Interfaces: Ensure that the signals and baud rate of main equipment match UM4B0
module’s
Antenna interface: Make sure the antenna impedance matching, and the circuit is
short and smooth, try to avoid acute angle
Try to avoid circuits below UM4B0
This module is a temperature sensitive device, dramatic changes in temperature will
result in reduced performance, keep it as far away from the high-power high-
temperature air and heating devices as possible
3.2 UM4B0 Reference Design
Figure 3-1 Minimum Reference Design

UM4B0 User Manual
11
Figure 3-2 UM4B0 Reference Design
3.3 Pins
Table 3-1 Pin Notes
Pin Name
Pin
I/O
Description
Notes
Power
Supply
VCC
31，32
Power
Voltage
Supply
Stable, clear low ripple power
supply, peak ripple power lower
than 50mVpp is preferred
ANT_PWR
5
Power
Antenna
Power
Supply
Voltage supply for
active antenna
GND
1, 3, 4,
6, 9, 14,
18, 25,
33, 34,
43, 47,
52, 55,
Power
Ground
Connect all the GND signals to
ground. Better use copper pour
surface.

12
Pin Name
Pin
I/O
Description
Notes
57, 58,
60
Antenna
ANT_IN
2
I
Satellite
signal input
50 Ωimpedance matching
UART
TXD1
35
O
COM1
Transmit
Data
COM1 output, leave
unconnected if no use
RXD1
36
I
COM1
Receive
Data
COM1 input, leave unconnected
if no use
TXD2
37
O
COM2
Transmit
Data
COM2 output, leave
unconnected if no use
RXD2
38
I
COM2
Receive
Data
COM2 input, leave unconnected
if no use
TXD3
39
O
COM3
Transmit
Data
COM3 output, leave
unconnected if no use
RXD3
40
I
COM3
Receive
Data
COM3 input, leave unconnected
if no use
System
FRESET_N
22
I
Hardware
Reset (low
effective)
Restore factory settings by
lowering FRESET_N for no less
than 5 seconds
PPS
44
O
PPS signal
PPS
EVENT
45
I
EVENT
signal
Event

UM4B0 User Manual
13
3.4 PCB Packaging
Figure 3-3 UM4B0 recommended PCB Packaging（unit：mil，in brackets：mm）
3.5 Reset Signal
UM4B0 module can’t work properly unless it is correctly reset after power on. To ensure
effective reset, the reset pin (RST) and power supply pin (VCC) must meet the following
time sequence. To reset UM4B0 during normal operation, please pull RST pin to low
level for more than 5ms.
VCC
RST
> 5ms
Figure 3-4 UM4B0 RST
3.6 Antenna
The module has the antenna input pin ANT_IN. It provides a +3.3V antenna feed, when
an active antenna of +3.3~5V is adopted, please make sure the 50 Ωantenna impedance
is matched.

14
ANT_IN UM4B0 Module
Figure 3-5 UM4B0 Active Antenna Connection
4Installation and Configuration
4.1 ESD Handling Precautions
UM4B0 Module is Electrostatic Sensitive Devices (ESD) device and requires special
precautions when handling.
Electrostatic discharge may cause damages to the device. All operations mentioned
in this chapter shall be carried out in an antistatic workbench, using both wearing
an antistatic wrist strap and a conductive foam pad. If antistatic workbench is not
available, wear an antistatic wrist strap and connect the other end to a metal frame
to play a role in anti-static
Hold the edge of the module, not in direct contact with the components
Please check carefully whether the module has obviously loose or damaged
components

UM4B0 User Manual
15
Figure 4-1 Typical Installation of UM4B0
Please check the contents of the package carefully after receiving the package of
UM4B0.
UM4B0 EVK suite (or evaluation board)
User manual
UPrecise software
Qualified antenna
MMCX antenna cable
PC or Laptop with serial ports (Windows XP/Win7 or later), with UPrecise installed
4.2 Hardware Installation
After the above preparation is made, please follow the steps below to install:
Step 1: Make sure to make full anti-static measures, such as anti-static wrist strap,
grounding the workbench;
Step 2: Align UM4B0 transfer board positioning holes and pins with EVK, and fix it in
the EVK. EVK provides power supply and standard communication interface for the
module, to communicate with peripheral devices;
NOTE: The RF joint of the card is MMCX, and the suitable connecting wire should be
selected according to the package. The input signal gain at the antenna interface is
optimal between 20 and 36 dB. Please select the appropriate antenna, antenna cable
and online LNA accordingly.

16
Figure 4-2 Installation Instruction
Step 3: Select the GNSS antenna with appropriate gain, fix it in the stable, non-block
area, using the coaxial radio frequency cable to connect the antenna with UM4B0
EVK;
Step 4: Connect the PC to the EVK serial port through direct serial cable;
Figure 4-3 Connect the Serial Port