# Presentation: 118075

## Portable Broadband Seismology

- Jakarta, Indonesia
- May 11-13, 2006
- Bruce Beaudoin
- Marcos Alvarez

- Part 5: Communication Options

## Communication Options

**Notes:**
Communication options

## VSAT

- Private vs Internet Accessibility
- Link Tuning
- Caveat
- Packet “eating”
- UDP checksum
- rain fade
- Modem hangs
- High power (>20W)
- Data rates: 256Kbps

**Notes:**
Vsat satellite system

This is fairly reliable, but sometimes the internet service providers filter out some of the data.
The modem can also crash and sometimes need rebooting,
Heavy rain can reduce the signal

## VSAT Telemetry Deployment

- VSAT
- Terminal

## DC Powered VSAT Site

**Notes:**
A battery powered and solar power system temporary site. Lots of power needed. Very heavy and expensive to install

## Station Communications Layout

**Seismic vault layout**

**Comm system layout**

** ****25 Watts DC power**
** ****AC preferred or 500 W solar array**
**Up to 50 km radio range**

** ****<3  Watts DC power**
**75 W solar array**
**~2 m vault depth**

- Seismic site and VSAT Communications separate wherever possible - data linked by radio
- Reduces power needs for remote site
- Decreased induced cultural noise from electronics and wind
- AC power for satellite system in most cases

**Notes:**
Using a radio transmission from the site to a location with AC power (doesn’t have the seismometer with it so it doesn't have to be quite.

## VSAT Regional Site

- VSAT install near barn with AC power

- Remote site uses RF radio to telemeter date to VSAT

**Notes:**
Example site

## Cell Modem

- Availability of service
- Service providers prefer bursting
- Low power (<1W)
- Data rate: 170Kbps

**Notes:**
If available can use the same technology as for hand phones. But the transfer can’t be contiuous, need to packet data as send in bursts

## Iridium Modem

- Availability of service
- Data rates too low for continuous data
- Caveat
- Link dropouts
- Modem hangs
- Intermediate power (4W)
- Data rate: 2.4Kbps

**Notes:**
A different satellite modem. Can be used for state of health data

## Ethernet

- Requires infrastructure
- Low power
- Caveat
- Network security issues
- Data rate: 1Mbps (Q330 throttle)

**Notes:**
Often have trouble with firewalls and internet security

## 900 MHz Ethernet Radio

- Line of site only (100 km)
- Point to point
- More tolerant to humidity/rain
- Caveat
- Can be affected by weather
- Low power (1.4W)
- Data rate: 115Kbps

**Notes:**
Need to be able to see the station from the base.

## 2.4 GHz Ethernet Bridge Radio

- Line of site only (60 km)
- Point to multi-point
- Caveat
- Can be affected by weather
- Other radio interference
- Intermediate power (4W)
- Data rate: 10Mbps

**Notes:**
One radio at the base can communicate to many sites. Therefore one satellite at a base can get data from several stations.

More affected by rain than the previous radio

## USArray TA Standard Site

## Realtime Date Rates

|  | Rate |
| --- | --- |
| 40 sps | 180 byte/s |
| 40 sps w/OH | ~360 byte/s |
| 100 sps | 450 byte/s |
| Iridium | 300 byte/s |
| Freewave | 15 KB/s |
| Cell Modem | 21 KB/s |
| VSAT | 32KB/s |
| Wilan | 1 MB/s |

**Notes:**
The top 3 are the rate of data collection (w/OH = with overhead – other communication information)

## Data Volumes

| 3 channels @ 1 sps | 11 MB/month |
| --- | --- |
| 3 channels @ 40 sps | 475 MB/month |
| 3 channels @ 100 sps | 1.2 GB/month |

**Notes:**
The amount of data collected in a month for different sample rates.

## Offload Time for 6 Months of 40 sps Data (~3GB)

|  | Rate | Time |
| --- | --- | --- |
| DAS | 10 Mbps | 40 mins |
| Wilan | 11 Mbps | 37 mins |
| Baler | 0.4 MBps | 125 mins |
| Cell | 21 KBps | 44 hrs |
| Iridium | 300 Bps | 2777 hrs |

**Notes:**
Time to download 3 GB using different connections

## Typical Portable DeploymentAnd ~ 1W Power Consumption (not including sensors)

## Application: Serial Telemetry

## Application: Ethernet Telemetry

- FRAD, DSL,

- ISDN, Radio,

- VSAT, Dial

- Ethernet

**TE**

- Data Port 1: Net Center 1

- Data Port 2: Net Center 2

- Data Port 3: status

- Data Port 4:

- Burst or Continuous TX

- to status

- to Net Center 1

- to Net Center 2

- intranet

## Serial Telemetry with Local Recording

- Serial port

**TE**

- Data Port 1: Net Center 1

- Data Port 2: Net Center 2

- Data Port 3: status

- Burst or Continuous TX

- Data Port 4: Baler Storage

- Burst or Continuous TX

- FRAD, DSL,

- ISDN, Radio,

- VSAT, Dial

- to status

- to Net Center 1

- to Net Center 2

## LAN-based Telemetry with Local Recording

- FRAD, DSL,

- ISDN, Radio,

- VSAT, Dial

- Ethernet

**TE**

- Data Port 1: Net Center 1

- Data Port 2: Net Center 2

- Data Port 3: status

- Data Port 4:  Baler Storage

- Burst or Continuous TX

- to status

- to Net Center 1

- to Net Center 2

## Remote Digitization with Telemetry to Recording and WAN Access Site

- Data Port 1: Net Center 1

- Data Port 2: Net Center 2

- Data Port 3: status

- Burst or Continuous TX

- Net Center 1

- Data Port 1: Net Center 1

- Data Port 2: Net Center 2

- Data Port 3: status

- Data Port 4: Baler Storage

- Burst or Continuous TX

- Status Application

- Net Center 2

- Internet

## USArray Communications

## GSN II Proposed Configuration